CHAPTER 29: Preinvasive Lesions of the Lower Genital Tract

Office gynecology frequently involves the diagnosis and management of preinvasive lower genital tract disease, most often involving the uterine cervix. Since widespread introduction of the Papanicolaou (Pap) test in the 1950s, cervical cancer screening has reduced the incidence of and mortality rate from invasive cervical cancer by more than 70 percent (Howlader, 2014). This is true despite a continued rise in the incidence of preinvasive lesions (Kurdgelashvili, 2013). Approximately 7 percent of U.S. women who undergo Pap testing will have an abnormal result (Wright, 2012). An abnormal screening test prompts further patient evaluation, usually with colposcopy and biopsy. Histologic results are more definitive and inform appropriate management.

In the lower genital tract (LGT), the term intraepithelial neoplasia refers to squamous epithelial lesions that are potential precursors of invasive cancer. These lesions demonstrate a range of histologic abnormality from mild to severe based on cytoplasmic, nuclear, and histologic changes. The severity of a squamous intraepithelial lesion is graded by the proportion of epithelium with abnormal cells from the basement membrane upward toward the surface. In the case of cervical intraepithelial neoplasia (CIN), abnormal cells confined to the lower third of the squamous epithelium are referred to as mild dysplasia or CIN 1, extending into the middle third as moderate dysplasia or CIN 2, into the upper third as severe dysplasia or CIN 3, and full-thickness involvement as carcinoma in situ (CIS) (Fig. 29-1). Squamous neoplasia of the vagina, vulva, perianal, and anal squamous epithelia (VaIN, VIN, PAIN, and AIN, respectively) are graded similarly with the caveat that VIN 1 is no longer recognized. The natural history of these extracervical lesions is less understood than for CIN. In contrast, the cervical columnar epithelium does not demonstrate an analogous neoplastic disease spectrum because it is only one cell-layer thick. Histologic abnormalities are therefore limited to either adenocarcinoma in situ (AIS) or adenocarcinoma.

The concept of cervical neoplasia as a spectrum has come under question with increasing insight into human papillomavirus (HPV) infection. Mild squamous dysplasia is now recognized as evidence of HPV infection, most of which is transient and unlikely to progress. Moderate to severe dysplastic squamous lesions are considered to be true cancer precursors. Current cytology reporting reflects this two-tier concept (Solomon, 2002). In 1989, the Bethesda System nomenclature replaced CIN with squamous intraepithelial lesion (SIL). Because cytologic and histologic changes of HPV infection and CIN 1 cannot be distinguished reliably and because of their like natural histories, they are categorized together as low-grade squamous intraepithelial lesions (LSIL). Similarly, CIN 2, CIN 3, and CIS are difficult to distinguish, are truer cancer precursors, and are all designated as high-grade squamous intraepithelial lesions (HSIL). The diagnostic distinction between LSIL and HSIL is more reliable, biologically plausible, and clinically meaningful than diagnoses using the CIN system. This two-tiered nomenclature is now recommended, and guidelines for the management of these lesions are grouped accordingly (Darragh, 2012).

External Genitalia

Precancerous lesions of the female LGT are often multifocal, can involve any of its structures, and may appear similar to benign processes. For example, micropapillomatosis labialis is a benign anatomic variant characterized by minute epithelial projections on the inner labia minora (Fig. 29-2). This condition can be easily mistaken for HPV-related lesions, but true HPV lesions tend to be multifocal and asymmetric, and to have multiple papillations arising from a single base (Ferris, 2004). Micropapillomatosis often shows spontaneous regression, and treatment is not indicated (Bergeron, 1990).

Vagina

The vagina is lined by nonkeratinized squamous epithelium, and glands are absent. However, areas of columnar epithelium are occasionally found within the vaginal squamous mucosa, a condition termed adenosis. It is often attributable to in utero exposure to exogenous estrogen, particularly diethylstilbestrol (DES) (Trimble, 2001). These areas are red patches within the squamous epithelium and can be mistaken for ulcers or other lesions. With DES-related adenosis, careful palpation of the vagina is warranted in addition to visual inspection, as clear cell adenocarcinoma may be palpable before becoming visible.

Cervix

Squamocolumnar Junction

During embryogenesis, upward migration of stratified squamous epithelium from the urogenital sinus and vaginal plate is thought to replace müllerian epithelium (Ulfelder, 1976). This process usually terminates near the external cervical os, forming the original (congenital) squamocolumnar junction (SCJ). When visible on the ectocervix, the SCJ is a pink, smooth squamous epithelium juxtaposed against the red, velvety columnar epithelium surrounding the external cervical os. Rarely, this migration is incomplete resulting in an SCJ in the upper vaginal fornices. This is a normal variant and also seen with in utero DES exposure.

The columnar epithelium is commonly referred to as “glandular.” This is because it produces mucus, and its deep infoldings appear histologically similar to glandular tissue (Fig. 29-3). However, true glands, consisting of acini and ducts, are not present on the cervix (Ulfelder, 1976).

The location of the SCJ varies with age and hormonal status (Fig. 29-4). During the reproductive years, it everts outward onto the ectocervix, especially during adolescence, pregnancy, and with combination hormonal contraceptive use. It regresses into the endocervical canal during the natural process of squamous metaplasia and in low-estrogen states such as menopause, prolonged lactation, and long-term progestin-only contraceptive use.

Squamous Metaplasia

At puberty, the rise in estrogen levels leads to increased glycogenation of the LGT nonkeratinized squamous epithelium. In providing a carbohydrate source, glycogen allows vaginal flora to be dominated by lactobacilli, which produce lactic acid. The resultant acidic vaginal pH is the suspected stimulus for squamous metaplasia, which is the normal replacement of columnar by squamous epithelium on the cervix. Relatively undifferentiated reserve cells underlying the cervical epithelia are the apparent precursors of the new metaplastic cells, which differentiate further into squamous epithelium. This normal process creates a progressively widening band of metaplastic and maturing squamous epithelium, termed the transformation zone (TZ), between the congenital (original) columnar epithelium and the squamous epithelium (Fig. 29-5).

Transformation Zone and Cervical Neoplasia

Nearly all cervical neoplasia, both squamous and columnar, develops within the TZ, usually adjacent to the new or current SCJ. Cervical reserve and immature metaplastic cells appear particularly vulnerable to the oncogenic effects of HPV and cocarcinogens (Stanley, 2010a). Squamous metaplasia is most active during adolescence and pregnancy. This may explain why early ages of first sexual activity and of first pregnancy are cervical cancer risk factors.

Basic Virology

The causative role of HPV in nearly all cervical neoplasia and a significant proportion of vulvar, vaginal, and anal neoplasia is firmly established. HPV primarily infects human squamous or metaplastic epithelial cells. It is a double-stranded DNA virus with a protein capsid unique to each viral type. More than 150 genetically distinct HPV types have been identified, and of these, approximately 40 types infect the LGT (Doorbar, 2012).

The circular HPV genome consists of only nine identified open reading frames (Stanley, 2010a). In addition to one regulatory region, the six “early” (E) genes govern functions early in the viral life cycle, including DNA maintenance, replication, and transcription. Early genes are expressed in the lower squamous epithelial layers (Fig. 29-6). The two “late” genes encode the major (L1) and minor (L2) capsid proteins. These proteins are expressed in the superficial epithelial layers late in the viral life cycle and during the assemblage of new, infectious viral particles. Sequential HPV gene expression is synchronous with and dependent on squamous epithelial differentiation. Thus, completion of the viral life cycle takes place only within an intact, fully differentiating squamous epithelium (Doorbar, 2012). This makes it nearly impossible to culture HPV in vitro. HPV is a nonlytic virus, and therefore infectiousness depends on normal desquamation of infected epithelial cells. A new infection is initiated when the L1 and L2 capsid proteins bind to the epithelial basement membrane and/or basal cells, permitting entry of HPV viral particles into cells of a new host (Sapp, 2009).

Genital HPV is the most common sexually transmitted disease (STD) in the United States, and most sexually active adults are infected at some time (Dunne, 2014). Most incident HPV infections develop in women younger than 25 years. The point prevalence in U.S. females aged 14 to 59 years is 27 percent. It is highest in those aged 20 to 24 years (45 percent) and becomes less prevalent with increasing age (Dunne, 2007). Clinically, HPV types are classified as high-risk (HR) or low-risk (LR) based on their strength of association with cervical cancer. LR HPV types 6 and 11 cause nearly all genital warts, laryngeal papillomas, and a minority of subclinical HPV infections. LR HPV infections are rarely, if ever, oncogenic.

In contrast, persistent HR HPV infection is now viewed as required for the development of cervical cancer. HR HPV types, including 16, 18, 31, 33, 35, 45, and 58, along with a few less common types, account for approximately 95 percent of cervical cancer cases worldwide (Muñoz, 2003). HPV 16 is the most oncogenic, accounting for the largest percentage of CIN 3 lesions (45 percent) and cervical cancers (55 percent) worldwide. It is also the dominant type in other HPV-related anogenital and oropharyngeal cancers (Schiffman, 2010; Smith, 2007). Although the prevalence of HPV 18 is much lower than that of HPV 16 in the general population, it is found in 13 percent of cervical squamous cell carcinomas, and in an even higher proportion of cervical adenocarcinomas and adenosquamous carcinomas (approximately 40 percent) (Bruni, 2010; Smith, 2007). Together, HPVs 16 and 18 account for approximately 70 percent of cervical cancers worldwide, 68 percent of squamous cell carcinomas, and 85 percent of adenocarcinomas (Bosch, 2008). HPV type 45 is the third most common found in cervical cancers (de Sanjose, 2010). HPV 16 accounts for more than 1 in 5 cervical HPV infections and is the most common HPV found among low-grade lesions and in women without neoplasia (Bruni, 2010; Herrero, 2000). Thus, HR HPV infection does not cause neoplasia in most infected women, and additional host, viral, and environmental factors determine progression to LGT neoplasia.

Transmission

The most important risk factors for the acquisition of genital HPV infection are the number of lifetime and recent sexual partners and early age at first sexual intercourse (Burk, 1996; Fairley, 1994; Franco, 1995). Genital HPV is transmitted by direct, usually sexual, contact with the genital skin, mucous membranes, or body fluids of an individual with either warts or subclinical HPV infection. The infectivity of inapparent (subclinical) HPV is assumed to be high. HPV is thought to access to the basal cell layer and basement membrane through microabrasions of the genital epithelium during sexual contact. Once infected, these basal cells may become a viral reservoir (Stanley, 2010b).

Cervical HR HPV infection generally requires penetrative intercourse. Oral-genital and hand-genital HPV transmissions are possible but are much less common than with genital-genital transmission (Winer, 2003). Women who have sex with women have rates of HR HPV positivity, abnormal cervical cytology, and high-grade cervical neoplasia similar to those of heterosexual women, but undergo cervical cancer screening less often. Women with or without past sexual experiences with men have a similar risk, implying that digital, oral, and perhaps object contact places them at risk of HR HPV infection (Marrazzo, 2000). Thus, all women who are sexually active should undergo cervical cancer screening according to current recommendations regardless of sexual orientation.

Genital HPV detection, including HR HPV, has been reported in apparently sexually naïve girls and young women (Doerfler, 2009; Winer, 2003). Nonetheless, genital warts that develop in children after infancy are always reason to consider the possibility of sexual abuse. HPV infection by nonsexual contact, autoinoculation, or fomite transfer appears possible. This is supported by reports of nongenital HPV types in a significant minority of pediatric and adolescent genital wart cases (Cohen, 1990; Obalek, 1990; Siegfried, 1997).

Congenital HPV infection from vertical transmission (mother to fetus or newborn) beyond transient skin colonization is rare. Conjunctival, laryngeal, vulvar, or perianal warts present at birth or that develop within 1 to 3 years of birth are most likely due to perinatal exposure to maternal HPV (Cohen, 1990). Infection is not linked to maternal genital warts or route of delivery (Silverberg, 2003; Syrjänen, 2010). Accordingly, cesarean delivery generally is not recommended for maternal HPV infection. Exceptions include cases of large genital warts that would obstruct delivery or might avulse and bleed with cervical dilation or vaginal delivery.

Infection Outcomes

Genital HPV infection causes variable outcomes (Fig. 29-7). These can be broadly grouped as latent or expressed infections. Infection expression may be productive, that is, creating infectious viral particles, or it may be neoplastic, causing preinvasive disease or malignancy. Most productive infections are subclinical, but a smaller percentage yields clinically apparent genital warts. Last, HPV infection can be transient or can become persistent. High-grade neoplasia (CIN 3 or worse) is the least common outcome of genital HPV infection, requiring HPV persistence.

Latent infection refers to that in which cells are infected, but HPV remains quiescent. There are no detectable tissue effects, as the virus is not actively replicating. The virus is present below detectable levels. Thus, it is uncertain whether apparent clearance of the HPV constitutes true eradication of HPV from infected tissues or whether it reflects latency.

Productive infections are characterized by viral life-cycle completion and plentiful production of infectious viral particles (Stanley, 2010a). Viral gene expression and assemblage are completed in synchrony with terminal squamous differentiation, concluding with desquamation of infected squames. These infections have little or no malignant potential because the HPV genome remains episomal and its oncogenes are expressed at very low levels (Durst, 1985; Stoler, 1996).

In both female and male genital tracts, productive HPV infections cause either visible genital warts (condyloma acuminata) or much more commonly, subclinical infections. Subclinical infections may be indirectly identified as low-grade cytologic, colposcopic, or histologic abnormalities. However, all these observational diagnoses are subjective and poorly reproducible. HPV testing more accurately reflects HPV infection but is limited to specific HPV types and viral loads.

With neoplastic infection (CIN 3 and cervical cancer), the circular HPV genome is disrupted and integrates at random locations into a host chromosome (Fig. 30-1). Unrestrained transcription of the E6 and E7 oncogenes follows (Durst, 1985; Stoler, 1996). The E6 and E7 oncoproteins produced interfere with and accelerate degradation of p53 and pRb, which are key tumor suppressor proteins produced by the host (Fig. 30-2). This leaves the infected cell vulnerable to malignant transformation by loss of cell-cycle control, cellular proliferation, and accumulation of DNA mutations over time (Doorbar, 2012).

In resultant preinvasive lesions, normal epithelial differentiation is disrupted and incomplete. The degree of disruption is used to grade histology as low-grade (encompassing HPV changes and CIN 1) or high-grade (CIN 2, CIN 3, and CIS). The average age at diagnosis of low-grade cervical disease is younger than that of high-grade lesions and invasive cancers. Thus, disease was thought to progress from milder- to higher-grade lesions over time. An alternative theory now proposes that low-grade lesions are generally acute, transient, and not oncogenic. High-grade lesions and cancers are monoclonal and arise de novo rather than from preexistent low-grade disease (Baseman, 2005; Kiviat, 1996).

The pathogenesis of HPV-related neoplasia at other anogenital sires is thought to be similar to that of the cervix. Genital HPV infection is usually multifocal and involves the cervix most often. Neoplasia at one site increases the risk of neoplasia elsewhere in the LGT (Spitzer, 1989).

Natural History of Infection

Infection with HPV, predominantly HR types, is very common soon after initiation of sexual activity (Brown, 2005; Winer, 2003). This infection often accompanies sexual debut and is not evidence of promiscuity (Collins, 2002).

Most HPV infection and related lesions, whether clinical or subclinical, spontaneously resolve, especially in adolescents and young women (Ho, 1998; Moscicki, 1998). Questions have been raised as to whether apparent clearance reflects true resolution or limited testing sensitivity (Winer, 2011). Several studies show that LR HPV infections resolve faster than those involving HR HPV (Moscicki, 2004; Schlecht, 2003; Woodman, 2001). Younger women frequently change HPV types, reflecting transience of infection and sequential reinfection by new partners rather than persistence (Ho, 1998; Rosenfeld, 1992). Simultaneous or sequential infection with multiple HPV types is common (Schiffman, 2010).

Persistent HR HPV infection is necessary for the development of cervical neoplasia. A minority of HPV infections become persistent, but most young women (65 percent) with HPV 16/18 infections lasting more than 6 months will develop SIL (Trottier, 2009). The risk of progression to high-grade neoplasia increases with age, as HPV infection in older women is more likely to reflect persistence (Hildesheim, 1999). Cell-mediated immunity likely plays the largest role in HPV infection persistence and in progression or regression of benign and neoplastic lesions.

Infection Diagnosis

HPV infection is suspected based on clinical lesions or results of cytology, histology, and colposcopy, all of which are subjective and often inaccurate. Moreover, serology is unreliable and cannot distinguish past from current infection (Dillner, 1999). As noted, culture of HPV is not feasible. Thus, diagnosis is confirmed only by the direct detection of HPV nucleic acids by methods that include in situ hybridization, nucleic acid amplification testing (NAAT), polymerase chain reaction (PCR), or others (Molijn, 2005). Currently, four HR HPV tests are approved by the Food and Drug Administration (FDA) for clinical use, and all use NAAT to detect any of 13 or 14 HR HPV types. Two of these tests report specifically the presence of HPV 16 or HPV 18 to aid risk stratification and customized management. Due to clinical test limitations, a negative test result does not exclude HPV infection. Therefore, these tests are not indicated or useful for routine STD screening. LR HPV testing has no indication and can lead to inappropriate expense, further evaluation, and unnecessary treatment.

The clinical role of HR HPV testing for cervical cancer screening and for surveillance of SIL continues to evolve. It is not offered as a screen for HPV infection outside of current guidelines. Namely, appropriate clinical uses for HR HPV testing include: cotesting with cervical cytology screening in women aged 30 years or older, triage or surveillance of certain abnormal cytology results and untreated CIN, and posttreatment surveillance (Davey, 2014). One HR HPV test (cobas HPV Test) was recently FDA approved as a stand-alone screening test for cervical cancer for women 25 years of age and older. If typical genital warts are found in a young woman or if high-grade cervical neoplasia or invasive cancer is identified by cytology or histology, then HPV infection is assumed, and HPV testing is unnecessary. Because of high HPV prevalence in young women (less than age 25), HR HPV testing for cervical cancer screening is not recommended. HPV testing is not FDA approved for use in women after complete hysterectomy, and there are no guidelines for managing HPV test results in these women.

Infection Treatment

The indications to treat HPV-related LGT disease are symptomatic warts, high-grade neoplasia, or invasive cancer. No effective treatment resolves subclinical or latent HPV infection. Needless physical LGT damage may result from unrealistic attempts to eradicate HPV infections, which are usually self-limited. Encouragement of positive health behaviors and optimal management of immune compromise seems sensible. Treatment of cervical LSIL (HPV changes or CIN 1) is not necessary and is considered only after observation for at least 2 years.

Various treatment modalities are available for genital warts and are chosen according to lesion size, location, and number (Rosales, 2014). Mechanical removal or destruction, topical immunomodulators, and chemical or thermal coagulation can be used (Table 3-15). Examination of a male partner does not benefit a female partner either by influencing reinfection or by altering the clinical course or treatment outcome for genital warts or LGT neoplasia (Centers for Disease Control and Prevention, 2010).

Infection Prevention

Behavior

Sexual abstinence, delaying coitarche, and limiting the number of sexual partners are logical strategies to avoid genital HPV infection and its adverse effects. However, evidence is lacking from trials of counseling and sexual practice modification. Condoms do not cover all potentially HPV-infected anogenital skin. Therefore, condoms may not be completely protective but are likely to reduce acquisition and transmission of HPV. Winer and associates (2003) conducted the first prospective study of male condom use and showed reductions in HPV infection rates in young women even if condoms were used inconsistently.

Vaccines

These offer the greatest promise for prevention and possibly reversal of its sequelae in those already infected. Local and humoral immunity likely protect against incident infection, and prophylactic vaccines elicit type-specific humoral antibody production that prevents new HPV infection by blocking its entry into host cells (Stanley, 2010b). They do not prevent transient HPV positivity or resolve preexistent infection. HPV vaccines have the potential to prevent malignancies at least six body sites that include cervix, vulva, vagina, penis, anal canal, and oropharynx.

Currently, three HPV vaccines are FDA approved for prevention of incident HPV infection and cervical neoplasia. They use recombinant technologies for the synthetic production of the L1 capsid proteins of each HPV type included in the vaccine. The resultant virus-like particles are highly immunogenic but are not infectious as they lack viral DNA (Stanley, 2010b).

Cervarix (HPV2) is a bivalent vaccine against HPVs 16 and 18. Gardasil (HPV4) is a quadrivalent vaccine against HPV types 6, 11, 16, and 18. HPV4 is being replaced by Gardasil 9 (HPV9), a nonavalent vaccine. HPV9 protects against all HPV types in HPV4 plus types 31, 33, 45, 52, and 58. Coverage of these additional HR HPV types will bring the theoretical percentage of cervical cancers prevented from 65 percent to approximately 80 percent. All three vaccines contain adjuvants that boost the immune response to vaccine antigens. They are administered in three intramuscular doses during a 6-month period. Specifically, the second dose is given 1 to 2 months after the first dose, and the third dose is given 6 months after the first dose. Prolongation of the dosing schedule does not appear to diminish immunogenicity. Optimal vaccination strategies administer these prior to sexual activity initiation, when the potential benefit is greatest. However, a history of prior sexual activity, HPV-related disease, or HPV-test positivity should not deter vaccine administration. Testing for HPV is not recommended prior to vaccination (American College of Obstetricians and Gynecologists, 2014a). The Advisory Committee on Immunization Practices (ACIP) currently recommends that HPV vaccine be administered routinely to girls aged 11 to 12 years (as early as age 9 years). Vaccination is also recommended for 13- to 26-year-old women not previously vaccinated (Markowitz, 2014; Petrosky, 2015). Vaccination can be given during lactation but is avoided during pregnancy (American College of Obstetricians and Gynecologists, 2014a). Immune compromised women are candidates to receive the vaccine and show high seroconversion rates despite the theoretical risk of a blunted immune response.

All three vaccines show nearly 100-percent efficacy in preventing incident infection and high-grade cervical neoplasia from HPV types included in the vaccines (Future II Study Group, 2007; Paavonen, 2009; Joura, 2015). HPV4 and HPV9 additionally protect against HPV types 6 and 11, which cause nearly all genital warts, laryngeal papillomatosis, and many low-grade cytologic abnormalities. HPV4 and HPV9 are approved for genital wart prevention in both males and females. They are also FDA approved for the prevention of vaginal, vulvar, and anal neoplasia. HPV2 does not prevent genital warts. It is not approved for extracervical LGT disease prevention, although theoretically it should.

HPV vaccines are highly immunogenic with maintenance of protection for at least 5 to 8 years after vaccination (Ferris, 2014; Harper, 2006). No evidence supports the need for later booster dosing. They have excellent safety profiles, are well-tolerated, and can be administered along with other recommended vaccinations.

Because HPV vaccines prevent most, but not all, HPV-related cervical cancers, cervical cancer screening should continue per current guidelines. Countries with high vaccination rates have seen dramatic reductions in anogenital warts, and reductions in Pap abnormalities and cervical neoplasia are expected (Ali, 2013). Despite suboptimal vaccination rates in the United States, HPV4 vaccine-type infections among U.S. adolescents have decreased by 56 percent since vaccine introduction in 2006 (Stokley, 2014).

Risk Factors

Henk and associates (2010) estimated that 412,000 cases of CIN are diagnosed in the United State annually. Risk factors are similar to those of invasive cervical cancer, and CIN is most strongly related to persistent genital HR HPV infection and increasing age (Table 29-1) (Ho, 1995; Kjaer, 2002; Remmink, 1995).

The median age of cervical cancer diagnosis in the United States (late fifth decade) is approximately a decade later than for CIN. In an older woman, HPV infection is more likely to persist than resolve. Older age is linked with waning immune competence and also allows accumulation of genetic mutations over time that can lead to malignant cellular transformation. Additionally, adverse socioeconomic factors and decreased need for prenatal care and contraception cause older women to be screened less often.

Behavioral risk factors for CIN mirror those for HPV acquisition and include early onset of sexual activity, multiple sexual partners, and male partner promiscuity (Buckley, 1981; de Vet, 1994; Kjaer, 1991). After adjustments for HPV positivity and lower socioeconomic status, tobacco use also increases the preinvasive disease risk (Castle, 2004; Plummer, 2003).

Dietary deficiencies of certain vitamins such as A, C, E, beta carotene, and folic acid may alter cellular immunity to HPV infection. This may promote viral infection persistence and cervical neoplasia (Paavonen, 1990). However, in the United States, lack of association between dietary deficiencies and cervical disease may reflect the relatively sufficient nutritional status of even lower-income women (Amburgey, 1993).

Combination oral contraceptives (COCs) have been linked with an increased risk of cervical cancer in current users (International Collaboration of Epidemiological studies of Cervical Cancer, 2007). Possible mechanisms include increased persistence of HPV infection and oncogene expression (de Villiers, 2003). Conversely, multiple studies have failed to find an increased CIN risk in users of hormonal contraceptives or postmenopausal hormone therapy (Castle, 2005; Harris, 2009; Yasmeen, 2006). DES exposure in utero appears to double the risk of developing high-grade cervical disease in addition to an increased risk of cervical and vaginal clear cell adenocarcinoma (Hoover, 2011).

Increasing parity has been correlated with cervical cancer risk, but it is unclear if this is related to earlier sexual activity, a progestin-exposure effect, or other factors. Immune suppression during pregnancy, hormonal influences on cervical epithelium, and physical trauma related to vaginal deliveries have all been suggested (Brinton, 1989; Muñoz, 2002).

Immunosuppressed women in general show increased risks for CIN and for greater lesion severity, multifocal lesion pattern, and lesions at multiple LGT sites. They also experience higher rates of treatment failure, persistence, and recurrence of LGT disease compared with those who are immunocompetent. Specifically, human immunodeficiency virus (HIV)-positive women have higher rates of abnormal Pap results and CIN compared with HIV-negative women. Transplant recipients have an increased risk of developing a malignancy after transplantation, including neoplasms of the LGT and anal canal (Gomez-Lobo, 2009). Women on immunosuppressive medications for other disorders have higher rates of LGT neoplasia.

Inadequate screening is another risk factor. Of women diagnosed with cervical cancer in the United States, approximately 60 percent either have never been screened (50 percent) or have not had a Pap test during the previous 5 years (10 percent) (American College of Obstetricians and Gynecologists, 2012b). Lack of screening is a major contributor to higher rates of cervical cancer in socioeconomically disadvantaged women, particularly those of minority ethnicity, rural residence, or older age, and those who are recent immigrants (Benard, 2007).

Natural History

Preinvasive lesions can spontaneously regress, remain stable, or progress. The risk of progression to invasive cancer increases with the severity of CIN. Estimates of CIN progression, persistence, and regression are provided in a review by Ostor (1993) and shown in Table 29-2. Low-grade lesions are thought to be manifestations of acute HPV infection, and most spontaneously regress within a few years. High-grade lesions are less likely to do so. Castle and coworkers (2009b) calculated that approximately 40 percent of CIN 2 regresses spontaneously within 2 years. This is even more frequent (greater than 60 percent) in young, healthy women (Moscicki, 2010). CIN 2 is thought to be a mixture of low- and high-grade lesions that are difficult to distinguish histologically, rather than an intermediate step in the progression from CIN 1 to CIN 3. The risk of progression to invasive cancer of biopsied but otherwise untreated CIN 3 lesions approximates 30 percent over 30 years (McCredie, 2008).

Cervical cancer screening ideally finds preinvasive lesions that can be eradicated or finds early-stage cervical cancer that can be treated successfully. Cervical cancer screening was previously limited to cervical cytology. But, during the past decade, HR HPV testing has also become an important screening tool.

In general, LGT preinvasive lesions are visible only with aided inspection. One exception is VIN, which is generally visible, palpable, or both. Only cervical lesions at either end of the neoplastic disease spectrum are grossly visible, namely, condylomata and invasive cancers. Accordingly, all symptoms suspicious for cervical neoplasia and grossly visible cervical lesions require prompt biopsy.

Cervical Cytology

Cervical cytologic screening is one of modern medicine’s great success stories. It detects most cervical neoplasia during the typically prolonged premalignant or early occult invasive phases, when treatment outcomes are optimal. Conventional glass slides (traditionally called the Pap smear) and liquid-based Pap tests are considered equally acceptable for screening by all current guidelines (American College of Obstetricians and Gynecologists, 2012b; Saslow, 2012; U.S. Preventive Services Task Force, 2012).

Introduced in the 1940s, cervical cytology has never been evaluated in a randomized, controlled, or masked trial (Koss, 1989). However, countries with organized screening programs have consistently realized dramatic declines in both cervical cancer incidence and mortality rates. The Pap test’s specificity is consistently high, approximating 98 percent. However, estimates of its sensitivity for detection of CIN 2 or worse are lower, are more variable, and range from 45 to 65 percent (Whitlock, 2011). This imperfect sensitivity is balanced by recommendations for repetitive screening throughout a woman’s life. Although the incidence of cervical squamous carcinoma continues to decline, both the relative and absolute incidences of adenocarcinoma have increased, particularly in women younger than 50 (Herzog, 2007). Adenocarcinoma and adenosquamous carcinoma now account for at least 20 percent of cervical cancers. This increase may be due in part to the Pap test’s lower sensitivity for detection of adenocarcinoma than for squamous cancers and their precursor lesions.

False-negative Pap test results may follow sampling error, in which abnormal cells are not present in the Pap test, or by screening error, in which the cells are present but missed or misclassified by the screener (Wilkinson, 1990). Mandated quality assurance measures and computerized slide-screening technologies address screening errors. Suboptimal management of abnormal results by providers and failure of patient follow up also contribute to avoidable cases of cervical cancer. Clinicians can maximize the benefit of screening by obtaining an optimal cytologic specimen and by adhering to current evidence-based guidelines for the management of abnormal test results.

Performing a Pap Test

Ideally, Pap tests are scheduled to avoid menstruation. Patients should abstain from vaginal intercourse, douching, vaginal tampon use, and intravaginal medicinal or contraceptive creams for a minimum of 24 to 48 hours before a test. Treatment of cervicitis or vaginitis prior to Pap testing is optimal. However, Pap testing is not deferred due to unexplained discharge or unscheduled bleeding, as these may be signs of cervical or other genital tract cancers.

As shown in Figure 21-9, the appearance of cervical squamous cells varies throughout the menstrual cycle and with hormonal status. Thus, clinical information aids accurate Pap interpretation and often includes: date of last menstrual period, current pregnancy, exogenous hormone use, menopausal status, complaints of abnormal bleeding, and prior abnormal Pap test results, CIN, or other LGT neoplasia. Additionally, intrauterine devices (IUDs) can cause reactive cellular changes, and their presence is noted. Full visualization of the cervix is essential for detection of gross lesions and SCJ identification. Speculum placement should be as comfortable as possible. A thin coating of water-based lubricant can be used on the outside of the speculum blades without compromising Pap test quality or interpretation (Griffith, 2005; Harmanli, 2010). Touching the cervix prior to performing a Pap test is avoided, as dysplastic epithelium may be inadvertently removed with minimal trauma. Discharge covering the cervix may be carefully absorbed by a large swab, with care not to contact the cervix. Vigorous blotting or rubbing may cause scant cellularity or a false-negative Pap test result. When indicated, additional sampling to detect other cervical or vaginal infection may follow Pap test collection.

Sampling of the transformation zone at the SCJ is paramount to the sensitivity of the Pap test. Techniques are adapted and sampling devices chosen according to SCJ location, which varies widely with age, obstetric trauma, and hormonal status. Women known or suspected of in utero DES exposure may also benefit from a separate Pap test of the upper vagina, as these women carry an additional risk for vaginal cancer.

Three types of plastic devices are commonly used to sample the cervix: the spatula, broom, and endocervical brush (also known as a cytobrush) (Fig. 29-8). A spatula predominantly samples the ectocervix. An endocervical brush samples the endocervical canal and is used in combination with a spatula. A broom samples both endo- and ectocervical epithelia simultaneously but can be supplemented by an endocervical brush. Wooden collection devices and cotton swabs are no longer recommended due to their inferior collection and release of cells.

A spatula is oriented to best fit the cervical contour, straddle the squamocolumnar junction, and sample the distal endocervical canal. A clinician firmly scrapes the cervical surface, completing at least one full rotation. After the spatula sample is obtained, the endocervical brush, with its conical shape and plastic bristles, is inserted into the endocervical canal only until the outermost bristles remain visible just within the external os. This prevents inadvertent sampling of lower uterine segment cells, which can be mistaken for atypical cervical cells. To avoid obscuring blood, the brush is rotated only one-quarter to one-half turn and is used after the ectocervix has been sampled. If the cervical canal is very wide, the brush is moved so as to contact all surfaces of the endocervical canal.

Broom devices have longer central bristles that are inserted into the endocervical canal. These longer bristles are flanked by shorter bristles that splay out over the ectocervix during rotation. Five rotations in the same direction are recommended. Reversing direction may cause loss of cellular material. Broom devices are favored for liquid-based Pap testing.

Cytology Collection

Conventional slide collection requires special care to avoid air drying artifact, a leading cause of poor slide quality. The spatula sample is held while the endocervical brush sampling immediately follows. The spatula sample is then quickly spread as evenly as possible over one half to two thirds of a glass slide (see Fig. 29-8). The endocervical brush is firmly rolled over the remaining area of the slide, after which fixation is quickly carried out by spraying from a distance of 10 to 12 inches or immersing the slide in fixative.

Currently, two liquid-based cytology (LBC) Pap tests are FDA approved. Sampling and cell transfer to a liquid medium is performed according to manufacturer specifications. SurePath allows for the use of all three device types but uses modified tips that are broken off and sent to the laboratory in the liquid medium. ThinPrep requires immediate and vigorous agitation of the chosen collection device(s) in the liquid medium, after which the device is discarded.

HPV Testing

A role for HR HPV testing in cervical cancer screening is attractive due to its improved sensitivity for CIN 3 or cervical cancer and the objectivity of its results. However, strategies for incorporation of HPV testing must compensate for a decreased specificity, particularly in young women.

Cytology with HPV Cotesting

In 2003, the FDA first approved an HPV test for use with cytology for cervical cancer screening in women 30 years and older. The combination of HR HPV testing with cytology is referred to as cotesting. This strategy is not currently endorsed for women younger than 30 due to the high prevalence of HR HPV infection in this age group and the resultant lack of test specificity. HPV testing is usually performed from the residual LBC specimen after the cytology slide is prepared. Alternatively, a cervical sampling for HPV can be sent in a specific collection device separate from the cytology specimen. Testing is performed only for HR HPV types. As noted earlier, there is no clinical role for LR HPV testing (Castle, 2014; Thomsen, 2014).

The combination of HPV testing with cytology increases the sensitivity of a single screening test for high-grade neoplasia to nearly 100 percent and leads to earlier detection and management of HSIL (Ronco, 2010). The lack of sensitivity for cervical adenocarcinoma seen with traditional cytology testing also supports HPV testing use for primary screening (Castellsagué, 2006).

Due to a high negative predictive value for high-grade neoplasia, slow progression of new HPV infection to neoplasia, and increased cost, cotesting is repeated at 5-year intervals if both cytology and HPV test are negative. Clinical guidelines have been developed for management of abnormal cotest results (Saslow, 2012). If cytology is abnormal, current cytology management guidelines are followed. Cytology-negative and HPV-positive test results will occur in less than 10 percent of screened patients (Castle, 2009a; Datta, 2008). In such cases, cotesting is repeated 12 months later. This is because the risk of high-grade neoplasia is less than that of a Pap test with an atypical squamous cell of undetermined significance (ASC-US) result, and most HPV infections will resolve during this time (Saslow, 2012). Colposcopy is recommended for persistently positive HPV DNA test results. An abnormal repeat cytology result is managed according to current guidelines regardless of concurrent HPV status.

An alternative strategy is now available for management of a negative cytology but a positive HR HPV test result. A reflex test specifically for HPVs 16 and 18, called genotyping, can be performed. If positive, immediate colposcopy is recommended (American College of Obstetricians and Gynecologists, 2012b; Saslow, 2012). This approach targets those at highest risk for significant disease, and evidence provides a sound basis for this strategy (Khan, 2005; Wright, 2015).

Primary HPV Testing

A growing body of evidence supports HR HPV testing alone without initial cytology as an option for primary cervical cancer screening (Castle, 2011; Cuzick, 2006; Dillner, 2013). In late 2014, the cobas HPV test was the first HPV test approved by the FDA for primary cervical cancer screening in women 25 years and older. This test gives simultaneous results for the presence or absence of HPVs 16 and 18 and for a group of 12 other oncogenic HPV types. This represents a profound paradigm shift in cervical cancer screening, in which Pap testing assumes a secondary role for the triage of HPV positive results.

HPV testing alone is approximately twice as sensitive (>90 percent) as a single Pap test and leads to earlier detection of high-grade neoplasias. The very high negative-predictive value of a single negative HPV test was shown by Sankaranarayanan (2009). During this 8-year study, a single round of HPV testing outperformed cytology, with no cervical cancer deaths within 8 years of a negative HR HPV test result. Recent evaluations show that cotesting does not perform any better than HPV testing alone (Dillner, 2013; Whitlock, 2011). However, specificity declines with HPV testing, particularly in younger women (Mayrand, 2007; Ronco, 2006, 2010). This could lead to excessive numbers of colposcopies, biopsies, and treatments. Triaging women with positive non-HPV16/18 HPV test results to reflex cytology is a viable counterbalance to the decreased specificity. Overall, this strategy is expected to result in more colposcopic referrals but yield higher and earlier HSIL detection rates.

Suggested interim guidelines for primary HPV test screening are recently published and will no doubt be debated and revised in coming years (Huh, 2015). These propose that screening with a HR HPV test can be used as an alternative to cytology alone or cotesting in women 25 years and older and at intervals no less than 3 years. Immediate colposcopy is recommended if HPV 16/18 is identified. If other HR HPV types are found, then triage to reflex cytology is proposed. Colposcopy is recommended for any cytologic abnormality. Importantly, as of mid-2015, major cervical cancer screening guidelines do not include this screening option.

Cervical Cancer Screening Guidelines

Perspective on Guidelines

Notably, all approved cervical cancer screening strategies, including the use of periodic cytology alone, dramatically reduce a woman’s lifetime risk of developing or dying from cervical cancer. Since most women with positive HR HPV test results will not develop significant disease, the choice of screening strategy should be a shared decision by the provider and individual patient. Reviewed by the National Cancer Institute (2015a), the balance of benefits and harms of each screening strategy warrants careful consideration by both health care providers and health care policy agencies. With that perspective, guidelines are subsequently presented.

Evidence-based cervical cancer screening guidelines continue to evolve. In 2012, all major professional societies updated these. The American Cancer Society, the American Society for Colposcopy and Cervical Pathology, and the American Society for Clinical Pathology (ACS/ASCCP/ACP) jointly issued guidelines (Saslow, 2012). The U.S. Preventive Services Task Force (USPSTF) (Moyer, 2012) and the American College of Obstetricians and Gynecologists (2012b) each published guidelines as well. These three sets of guidelines agree with few exceptions and pertain only to average-risk women, that is, immunocompetent women with no history of HSIL or cervical cancer. All agree on the acceptability of both conventional and liquid-based Paps, the age of initiation and cessation of screening, screening intervals, and continued screening after HPV vaccination. Adherence to current guidelines should not preclude or delay other indicated gynecologic care. In particular, provision of contraception is never contingent on compliance with cervical cancer screening recommendations or the evaluation of cytologic abnormalities.

Screening Initiation

Cervical cancer screening ideally begins at age 21 in average-risk women. This is true regardless of sexual history, sexual orientation, or other risks. In young women, most Pap abnormalities represent transient HPV infection, and the spontaneous regression of even high-grade lesions is common (Moscicki, 2005). Most high-grade lesions are CIN 2 rather than CIN 3 in young women (Moscicki, 2008). Cervical cancer is exceedingly rare in adolescents and not as preventable by screening as for older women (Saslow, 2012). Additionally, treatment of high-grade CIN in adolescents is often followed by persistence of Pap abnormalities, and theoretically may have adverse reproductive consequences (Case, 2006; Moore, 2007).

Whether to begin screening earlier in the presence of significant immune compromise, as with HIV infection, use of immunosuppressive medications, and organ transplantation, is uncertain and not addressed by current guidelines. The Centers for Disease Control and Prevention (CDC) (2015) recommends initiation of screening soon after HIV diagnosis, even if before age 21, and repeat Pap testing in 6 months. As for other such conditions, clinician judgment is exercised, taking into consideration age and severity of immune compromise. In general, initial screening at age 21 seems reasonable (American College of Obstetricians and Gynecologists, 2012a).

Screening Interval and Strategy

Between ages 21 and 29, all guidelines recommend screening with cytology alone at 3-year intervals. Women aged 30 to 65 can continue screening with cytology alone at 3-year intervals or can begin cotesting at 5-year intervals. The risk of cancer is approximately the same using either strategy. USPSTF sees both strategies as equally effective, and cotesting is available to women wishing to extend their screening interval. However, both the ACS/ASCCP/ACP (Saslow, 2012) and American College of Obstetricians and Gynecologists (2012b) have deemed cotesting the preferred screening strategy in women 30 years and older. Women with HIV infection and other immune suppression should receive annual cytology screening (Centers for Disease Control and Prevention, 2015; American College of Obstetricians and Gynecologists, 2012a).

Screening Discontinuation

Screening may be stopped in women older than 65 if they have an average risk for cervical cancer and have undergone adequate screening, regardless of sexual history. Adequate screening is three consecutive, negative Pap results or two consecutive, negative cotest results in the prior 10 years, with the most recent within the past 5 years. Women with prior treatment for CIN 2, CIN 3, AIS, or cervical cancer should continue routine screening for at least 20 years, as they remain at increased long-term risk of cervical cancer (Saslow, 2012; Strander, 2007). It is uncertain when HIV-positive women can discontinue screening or whether this should continue annually and indefinitely for as long as there is reasonable life expectancy.

Posthysterectomy

Vaginal cancers are rare and account for less than 2 percent of cancers in women. All guidelines recommend against Pap screening in women who have undergone total hysterectomy for benign disease if there is no past history of high-grade CIN or cervical cancer. The absence of a cervix should be confirmed by examination or pathology report as many women are inaccurate in their reporting of hysterectomy type. Women who have undergone supracervical hysterectomy should continue routine screening. Recommendations for vaginal cytology after hysterectomy in women with histories of high-grade cervical neoplasia or cancer are less clear, as vaginal cancer is still rare, and screening is of uncertain benefit (Saslow, 2012). The American College of Obstetricians and Gynecologists (2012b) recommends cytology of the vaginal cuff every 3 years for 20 years after the initial posttreatment surveillance, which is generally a schedule of three Pap tests in the first 2 years posthysterectomy. HPV testing is not FDA-approved in the absence of a cervix but remains common. Evidence-based recommendations for managing vaginal HPV test results are nonexistent (Chappell, 2010). Such testing should be avoided.

The Bethesda System

Cervical cytology reporting is standardized by the Bethesda System nomenclature (National Cancer Institute Workshop, 1989; Nayar, 2015; Solomon, 2002). Clinically, the key elements reported are specimen adequacy and epithelial cell abnormalities (Tables 29-3 and 29-4). An overview of evidence-based guidelines for the initial management of cervical cytology abnormalities for nonpregnant women follows in the next paragraphs (American College of Obstetricians and Gynecologists, 2013; Massad, 2013). Full guidelines should be reviewed and applied on an individualized basis. Guidelines cannot address all clinical situations or prevent all cervical cancers.

Specimen Adequacy

This is reported as satisfactory or unsatisfactory for evaluation and is based primarily on criteria for slide cellularity and the presence of obscuring blood or inflammation. The presence or absence of TZ components, that is, endocervical and/or squamous metaplastic cells, is also reported. A TZ component is not required for test adequacy. Although its presence is associated with increased detection of cytologic abnormalities, its absence is not associated with failure to diagnose CIN. Pap tests lacking TZ components are repeated in 3 years. For women 30 years and older, HPV testing is preferred and further testing is guided by results.

Unsatisfactory Pap tests are unreliable for the detection of cervical neoplasia and also for HR HPV by some HPV tests. Unsatisfactory Pap tests are repeated in 2 to 4 months. If atrophy or a specific infection is present, treatment before repeat cytology may be helpful. If the result is unsatisfactory again, colposcopy is recommended as this persistent result confers increased CIN risk. Rarely, obscuring blood or inflammation on cervical cytology may indicate invasive cancer. Therefore, unexplained vaginal discharge, abnormal bleeding, or abnormal physical findings should prompt immediate evaluation rather than waiting for repeat Pap testing.

Epithelial Cell Abnormality Management

A cytology report is a medical consultation that interprets a screening test and does not provide a diagnosis. A final diagnosis is determined clinically, often with results from histologic evaluation. Pap tests are interpreted as either being negative for intraepithelial lesion or malignancy (NILM) or demonstrating one or more epithelial cell abnormalities.

Atypical Squamous Cells of Undetermined Significance

The most common cytologic abnormality is ASC-US. This term indicates cells that suggest SIL but do not fulfill all the criteria. An ASC-US result often precedes the diagnosis of CIN 2 or 3, but this risk approximates only 5 to 10 percent. Cancer is found in only 1 to 2 per thousand (Solomon, 2002).

Management of ASC-US without HPV cotesting is repeat cytology in 1 year, and this is preferred for women aged 21 to 24. If the repeat Pap test result is abnormal, colposcopy is recommended. Reflex HPV testing is preferred in women 25 years and older and acceptable in those age 21 to 24 years. Reflex testing refers to HPV testing in response to a specific result and is not performed if cytology is negative. With an ASC-US Pap result, reflex HPV testing is a good discriminator of those with high-grade CIN and those without. ASC-US, HPV-positive test results have a risk profile similar to LSIL results and thus are evaluated with colposcopy. ASC-US, HPV-negative results are followed up with a cotest in 3 years or with cytology alone in women under age 25.

Low-grade Squamous Intraepithelial Lesion

LSIL encompasses the cytologic features of HPV infection and CIN 1 but carries a 15 to 30 percent risk of CIN 2 or 3, similar to ASC-US, HPV-positive. Therefore, colposcopy is generally indicated for LSIL cytology.

Specifically, for LSIL with no HPV testing or with HPV-positive results, colposcopy is indicated in women aged 25 years and older. If a negative HPV test result is obtained due to cotesting, a repeat cotest in 1 year is preferred, but colposcopy is acceptable. Reflex HPV testing with an LSIL result is not useful in reproductive-aged women, as 75 to 85 percent will test positive for HR HPV. In women aged 21 to 24 years with an LSIL result, cytology follow-up is preferred to immediate colposcopy due to high rates of resolution. For postmenopausal women with LSIL and no HPV cotest, options include repeat cytology at 6 and 12 months, HPV testing, or colposcopy.

Atypical Squamous Cells, Cannot Exclude HSIL

Five to 10 percent of ASC is designated as atypical squamous cells, cannot exclude HSIL (ASC-H). This finding should not be confused with ASC-US. ASC-H describes cellular changes that do not fulfill criteria for HSIL cytology, but a high-grade lesion cannot be excluded. Histologic HSIL is found in upward of 25 percent of these cases, which is a higher rate than seen with ASC-US or LSIL. Thus, colposcopy is indicated regardless of age or concurrent HPV test result. Reflex HPV testing is not helpful due to a high rate of HPV-positivity. If colposcopy is inadequate, a diagnostic excision procedure is recommended.

High-grade Squamous Intraepithelial Lesion

HSIL cytology encompasses features of CIN 2 and CIN 3 (Fig. 29-9). It carries an elevated risk of underlying histologic HSIL (at least 70 percent) or invasive cancer (1 to 2 percent) (Kinney, 1998). Colposcopic evaluation is warranted for all HSIL cytology regardless of age or HPV status. Alternative management of HSIL cytology in women 25 years and older includes immediate loop electrosurgical excision procedure (LEEP), which is referred to as a see-and-LEEP approach. This strategy is reasonable because colposcopy may miss a high-grade lesion, and most HSIL cytologies eventually result in excision for diagnosis or treatment. Inadequate colposcopy should prompt excision unless initial biopsies show invasive cancer.

Glandular Cell Abnormalities

This group includes atypical glandular cells (AGC); AGC, favor neoplasia; and AIS. This category carries an increased risk of neoplasia (Zhao, 2009). Paradoxically, squamous neoplasia is more frequently diagnosed than glandular neoplasia upon evaluation of AGC cytology (Schnatz, 2006). There is also an elevated risk of endometrial and other reproductive tract cancers and cancers at other sites such as breast and colon. Approximately half of the neoplasia diagnosed subsequent to an AGC Pap is endometrial.

Accordingly, initial evaluation of a glandular abnormality includes colposcopy and endocervical sampling. It also includes endometrial sampling in patients 35 years and older or in younger women with risk factors for endometrial disease, which include abnormal bleeding or history suggesting chronic anovulation. If atypical endometrial cells are specified in the report, then initial endometrial and endocervical sampling is acceptable with subsequent colposcopy if these are negative.

Reflex HPV testing is not recommended for the triage of glandular cytologic abnormalities. Indeed, a negative reflex HPV test result may dissuade appropriate evaluation of AGC cytology. However, HPV testing at the initial evaluation of AGC may help distinguish cervical from endometrial disease (Castle, 2010; de Oliveira, 2006).

If initial evaluation of glandular cytologic abnormalities is negative, management and surveillance are generally aggressive due to the significant risk of occult disease. Current guidelines should be followed (American College of Obstetricians and Gynecologists, 2013; Massad, 2013). Diagnostic excision is indicated following AGC, favor neoplasia and AIS Paps if initial evaluation does not result in a cancer diagnosis.

Carcinoma

Cytologies suspicious for squamous cell carcinoma or adenocarcinoma carry the highest risk of invasive cancer and are evaluated promptly. If initial evaluation fails to reveal invasive cancer, a diagnostic excision procedure is indicated.

Pregnancy

Pregnant patients 21 years and older are screened and their abnormal cytologies managed according to guidelines for the general population. However, deferred evaluation of ASC-US and LSIL cytologies until at least 6 weeks postpartum is acceptable (Massad, 2013). When indicated, the goal of colposcopy is to exclude invasive cancer. Colposcopy and ectocervical biopsy are safe and accurate during pregnancy (Economos, 1993). Endocervical and endometrial sampling are not performed during pregnancy to avoid amnionic membrane rupture and infection. Preinvasive neoplasia is not treated but rather is reevaluated postpartum. This is because lesion progression is typically slow and lesion grade may change during delivery and puerperal remodeling (Yost, 1999). Although cervical conization is infrequently performed during pregnancy, indications for this are discussed in Chapter 30.

Nonneoplastic Findings

Certain nonneoplastic findings may be reported, and these include findings consistent with, but not conclusively diagnostic of, certain organisms. These findings include Trichomonas vaginalis, Candida species, Actinomyces species, herpes simplex virus, or shift in flora consistent with bacterial vaginosis. Sensitivity is generally limited, and accuracy of diagnosis varies (Fitzhugh, 2008). For this reason, confirmatory tests or clinical correlation should dictate any actions related to these findings. Other nonneoplastic findings are reactive changes associated with inflammation or repair, radiation changes, atrophy, and posthysterectomy benign glandular cells. None of these require a clinical response.

Benign endometrial cells seen in the cervical cytology of a postmenopausal woman confer an increased risk of endometrial hyperplasia and cancer. Because menstrual history and menopausal status are often unknown to the cytologist, benign endometrial cells are reported on cervical cytology for all women 45 years and older (Nayar, 2015). Premenopausal women do not require endometrial evaluation in the absence of abnormal bleeding.

Colposcopy

Preparation

This outpatient procedure examines the lower anogenital tract with a binocular microscope affixed to a stand and requires skills that encompass colposcopic terminology, lesion identification and grading, and biopsy techniques. Its primary goal is to identify invasive or preinvasive neoplastic lesions for directed biopsy and subsequent management. It remains the gold standard evaluation of patients with abnormal cervical cytology. However, its sensitivity, interobserver agreement, and reproducibility are less than previously thought. Sensitivity estimates range between 50 and 80 percent (American College of Obstetricians and Gynecologists, 2013; Ferris, 2005; Jeronimo, 2007). This highlights the need for further evaluation or surveillance when initial colposcopy fails to reveal high-grade neoplasia.

There are many styles of colposcopes, but they all operate similarly. The colposcope contains a stereoscopic lens or digital imaging system that has magnification settings ranging from 3- to 20-fold. Its stand allows positioning, and a high-intensity light provides illumination. A green (red-free) light filter adds contrast to aid vascular pattern evaluations (Fig. 29-10).

Prior to colposcopic examination, a woman’s medical history and record are reviewed and indications for colposcopy confirmed (Table 29-5). Urine pregnancy testing is performed if clinically indicated. Colposcopic examination is optimally timed to avoid menses. However, it is not delayed in the patient with a visible lesion, abnormal bleeding, or poor appointment compliance. In cases of severe cervicitis or other pelvic infection, treatment may be indicated before performing biopsies or endocervical curettage. Notably, abnormal cervical discharge in the absence of an identified pathogen may be a cancer indicator. A Pap test performed at the time of colposcopy is of questionable value, may obscure colposcopic findings, and should be performed on an individualized basis.

Solutions may aid colposcopic examination and are applied by gently dabbing a saturated swab or sponge or by spray-bottle misting so as not to traumatize the cervical epithelium. High-grade cervical lesions are particularly fragile. To begin, normal saline can help remove cervical mucus and allows initial assessment of vascular patterns and surface contours. Abnormal vessels, especially when viewed with green-filtered light, may be more prominent before acetic acid application.

Acetic acid in a 3- to 5-percent solution is a mucolytic agent thought to exert its effect by reversibly clumping nuclear chromatin. This causes neoplastic lesions to assume a thicker density and hues of white depending on the degree of abnormal nuclear density. Applying acetic acid to abnormal epithelium results in the acetowhite change characteristic of neoplastic lesions and of some benign conditions. Several minutes may be needed for this effect to become fully developed.

Dilute Lugol iodine solution stains mature squamous epithelial cells a dark purple-brown color in estrogenized women as a result of high cellular glycogen content. Due to incomplete cellular differentiation, dysplastic cells have lower glycogen content, fail to fully stain, and appear various shades of yellow (Fig. 29-11). This solution is particularly useful when abnormal tissue cannot be found using acetic acid alone. It is also used to define the limits of the active TZ, as immature squamous metaplasia does not stain as strongly as mature (fully differentiated) squamous epithelium. Lugol solution should not be used in patients allergic to iodine, radiographic contrast, or shellfish.

Examination

Two major components of colposcopic examination are general assessment and specific colposcopic findings. Careful description of these aids diagnosis and management of abnormalities. For this, standard colposcopic terminology used in the United States differs somewhat from that proposed by the International Federation for Cervical Pathology and Colposcopy (IFCPC) (Bornstein, 2012).

General colposcopic assessment has three components: cervical visualization, SCJ visibility, and TZ classification. First, every examination is characterized by whether the cervix is fully seen or whether the evaluation is limited by inflammation, bleeding, scarring, or other obscuring causes. The IFCPC labels full cervix visualization as “adequate” and otherwise as “inadequate.” However, current guidelines for management of abnormal cervical cytology and precancers issued by the ASCCP and standard U.S. practice reserve these descriptors for visibility of the SCJ and any lesions present (Massad, 2013).

Second, SCJ visibility is important, as nearly all cervical neoplasia is located within the TZ and at or adjacent to the SCJ. Within a neoplastic lesion, the most severe disease tends to be at the proximal (cephalad or upper) limit of the lesion. Therefore, the ability to see the entire SCJ and the upper limits of all lesions is essential to exclude invasive cancer and to determine disease severity. The IFCPC terminology characterizes the SCJ separately as completely, partially, or not visible. Current ASCCP guidelines define full visualization of both the SCJ and upper limits of all lesions present as “adequate.” Otherwise, the examination is “inadequate” (Fig. 29-12). Finally, the IFCPC classifies the TZ location as types 1, 2, or 3. A type 1 TZ is entirely ectocervical and visible; a type 2 has an endocervical component that is fully visible; and a type 3 TZ has an endocervical component that cannot be completely visualized. Types 2 and 3 may have ectocervical TZ components of varying extent. If treatment is indicated, the size and location of the SCJ, TZ, and visible lesions are important determinants of the modality chosen.

Lesion Grading

Colposcopically, normal squamous epithelium of the cervix appears as a featureless, smooth, pale-pink surface. Blood vessels lie below this layer and therefore are not visible or are seen only as a fine capillary network. The mucin-secreting columnar epithelium appears red due to its thinness and the close proximity of blood vessels to the surface. It has a polypoid appearance due to infoldings that form peaks and clefts (see Fig. 29-3). Against this normal colposcopic landscape, colposcopists discern abnormal tissue and choose for biopsy the sites most likely to harbor the most severe neoplasia. Several colposcopic grading systems quantify lesion qualities to improve diagnostic accuracy (Coppleson, 1993; Reid, 1985). Best known, the Reid Colposcopic Index is based on four lesion features, which are margin, color, vascular pattern, and Lugol solution staining. Each category is scored from 0 to 2, and the summation provides a numeric index that correlates with histology (Table 29-6).

The IFCPC has proposed a standardized nomenclature for lesion grading and recommends that it replace prior terminologies (Bornstein, 2012). Lesions with low-grade characteristics are labeled grade 1 (minor) lesions, whereas higher-grade characteristics are grade 2 (major) findings.

Of Reid index features, lesion margins and color are best assessed following application of acetic acid. The color or degree of whiteness obtained, rapidity and duration of acetowhitening, and sharpness of lesion borders are observed. Grade 2 (major or high-grade) lesions demonstrate a more persistent, duller shade of white, whereas grade 1 (minor or low-grade) lesions are translucent or bright white and fade quickly. Generally, grade 1 lesions have feathery or irregular “geographic” margins, whereas grade 2 lesions have straighter, sharper outlines (Figs. 29-13 and 29-14). Other lesion features suggestive of a high-grade lesions are: internal borders (inner border sign), an opaque protuberance within a lesion (ridge sign), and cuffed crypt openings.

Abnormal vascular patterns include punctation, mosaicism, and atypical vessels. Punctate and mosaic patterns are graded on the basis of vessel caliber, intercapillary distance, and the uniformity of each of these. Fine punctation and mosaicism, which are created by narrow vessels and short, uniform intercapillary distances, typify low-grade (grade 1) lesions. A coarse pattern results from wider and more variable vessel diameters and spacing and indicates high-grade (grade 2) abnormalities. Atypical vessels are irregular in caliber, shape, course, and arrangement and raise suspicion for invasive cancer (Fig. 29-15).

Biopsy

Ectocervical Biopsy

Under direct colposcopic visualization, suspicious lesions are biopsied using cervical biopsy forceps (Fig. 29-16). Generally, cervical biopsy does not require an anesthetic. Thickened Monsel solution (ferric subsulfate) or a silver nitrate applicator are applied with pressure to the biopsy site, providing hemostasis if needed. Heavier bleeding is rare and can be controlled with direct pressure or brief vaginal packing.

Traditionally, biopsies have been limited to the most severe-appearing lesions. However, two studies have shown that colposcopically directed biopsy detects only 60 to 70 percent of high-grade disease. Disease detection rates increase with the addition of random biopsies of normal-appearing epithelium and with the total number of biopsies taken (Gage, 2006; Pretorius, 2004; Zuchna, 2010)). The American College of Obstetricians and Gynecologists (2013) recommends biopsy of all acetowhite lesions regardless of colposcopic impression, and repeat colposcopic evaluation is suggested for persistent low-grade cytologic abnormalities or HPV-positive results to counter the imperfect detection of HSIL by colposcopy.

Endocervical Sampling

For nonpregnant patients, endocervical sampling by curettage or brushing evaluates the endocervical canal epithelium that lies beyond the colposcope’s view. Endocervical sampling is currently recommended during colposcopy in the following situations (American College of Obstetricians and Gynecologists, 2013; Massad, 2013):

• Colposcopy is inadequate, or colposcopy is adequate but no lesion is identified. Endocervical sampling is acceptable in other cases at provider discretion.

• Initial evaluation of ASC-H, HSIL, AGC, or AIS cytology test results.

• Surveillance 4 to 6 months after excisional therapy if specimen margins are positive for HSIL.

• Surveillance after conization for AIS has been performed in women wishing fertility preservation. Negative endocervical curettage results add reassurance to this management (Schorge, 2003).

Endocervical sampling can be performed by either curettage or brushing. Endocervical curettage is performed by introducing an endocervical curette 1 to 2 cm into the cervical canal (see Fig. 29-16). The length and circumference of the canal is firmly curetted, carefully avoiding sampling of the ectocervix or the lower uterine segment. Endocervical scrapings admixed with cervical mucus are then removed using a ring forceps or cytobrush and included with the curettage specimen. Alternatively, vigorous brushing with a cytobrush may be used to obtain an endocervical tissue specimen. Endocervical brushing is more sensitive than curettage, but grading of any dysplasia present is more difficult. Endocervical sampling is often the most uncomfortable part of a colposcopic evaluation, and cramping is common.

Evidence-based guidelines for the management of women with biopsy-confirmed CIN were developed by the ASCCP and updated in 2012 (Massad, 2013). These continue to use the CIN nomenclature since outcome data stratified by the newer SIL terminology are not yet available. Management of CIN involves either observation or treatment. Goals are to diagnose occult invasive cancer, detect progression of minor abnormalities, and treat high-grade dysplasia to decrease cancer risk. Detection and prevention of invasive cervical cancer, a relatively rare outcome, must be balanced against the potential harms of excessive testing and overtreatment that include procedure-related morbidities, possible adverse reproductive outcomes, and psychologic stress.

Special populations considered include women age 21 to 25 years and pregnant women. Immunosuppressed women are no longer considered a special population and can now be managed in accordance with general guidelines. However, the CDC (2010) and American College of Obstetricians and Gynecologists (2013) still question HPV testing for ASC-US triage and surveillance of HIV-positive women.

In general, women with higher grades of Pap abnormality and CIN, inadequate colposcopic examinations, abnormal endocervical samplings, and age older than 24 years are considered at higher risk of invasive cancer and are managed more aggressively. An overview of current CIN management guidelines for nonpregnant patients is presented here, but providers should consult comprehensive recommendations (American College of Obstetricians and Gynecologists, 2013; Massad, 2013). Guidelines are complex and are applied on an individualized basis, as they cannot address all clinical scenarios or individual patient situations. No guidelines can prevent all cases of cervical cancer.

CIN 1

CIN 1 exhibits a high rate of spontaneous regression. This diagnosis is poorly reproducible and thus unreliable. For this reason, CIN 1 is no longer treated aggressively. When diagnosed after a “lesser” cytologic abnormality such ASC-US, LSIL, or a negative Pap with either an HPV 16/18 genotype-positive or a persistent HR HPV-positive result, it can be observed indefinitely. Treatment is acceptable only if CIN 1 persists for more than 2 years regardless of colposcopic examination adequacy or presence of CIN 1 in an endocervical sampling. Treatment of CIN 1 in women under age 25 years is not recommended, even if persistent.

Observation consists of a cotest 12 months after CIN 1 diagnosis. If this is negative, resumption of routine screening is recommended 3 years later. In women age 21 to 25 years, observation with cytology alone at 12 months and 24 months is recommended instead of cotesting due to high rates of HPV positivity in this population. If CIN 1 is detected only in the endocervical sampling, sampling is repeated in 1 year in addition to other recommended surveillance. Abnormal surveillance results are followed by repeat colposcopy. Persistent CIN 1 may be treated by ablation or excision provided the colposcopic examination is adequate and endocervical sampling lacks HSIL (CIN 2/3) or ungraded CIN. If these criteria are not met, excision is recommended and ablation is unacceptable.

CIN 1 diagnosed after an ASC-H or HSIL Pap test result carries a higher risk of occult high-grade CIN. In women age 25 years or older with an adequate colposcopic examination, either a diagnostic excision or observation with cotesting at 12 and 24 months is acceptable. If colposcopy is inadequate, a diagnostic excision is indicated. Women age 21 to 24 years with CIN 1 diagnosed after a high-grade Pap abnormality can be monitored by colposcopic evaluation and cytology at 6-month intervals provided the colposcopic examination is adequate and endocervical samplings negative. Otherwise, excision is recommended. Persistent unexplained HSIL cytology results after 24 months of observation warrant an excision procedure.

CIN 2 and CIN 3

Generally, treatment is recommended for CIN 2 or 3 due to its significant malignant potential and the efficacy of treatment in preventing progression. Either ablation or excision is acceptable and is chosen according to individual patient, cervical TZ, and lesion characteristics.

When CIN 2/3 or ungraded CIN is found in an endocervical sampling or with an inadequate colposcopic examination, a diagnostic excision is needed to exclude occult invasive cancer. An unequivocal histologic diagnosis of CIN 3 is treated, not observed, regardless of age or reproductive history. Recurrence or persistence is treated with repeat excision, not ablation. Hysterectomy as primary therapy is unacceptable. It may be indicated if repeat excision is needed but not anatomically feasible or if high-grade CIN recurs or persists.

For young women, particularly of low parity, with CIN 2 or CIN 2/3 (HSIL, not otherwise specified) either observation or treatment are acceptable if colposcopy is adequate. In this context, “young women” refers to those individuals for whom the possible risk to future pregnancies from treatment outweighs the risk of progression to malignancy, although either of these is difficult to quantify. No upper age limit is recommended. Observation consists of repeat cytology and colposcopy at 6-month intervals. Observation of CIN 2 is preferred to treatment in younger women. If colposcopy is inadequate, CIN 3 is specified, or CIN 2 or CIN 2/3 persists at 24 months, then treatment is recommended.

Adenocarcinoma in Situ

Adenocarcinoma in situ (AIS) of the cervix, although uncommon, is increasing in incidence and typically diagnosed at a younger age (Herzog, 2007). Exclusion of invasive cancer and removal of all affected tissue are primary clinical goals. Management differs somewhat from that of CIN2/3 because AIS and adenocarcinoma are not easily identified colposcopically. Lesions can be multifocal, located deep within endocervical clefts, and extend farther into the endocervical canal (Massad, 2013). Diagnostic excision is required to exclude invasive cancer with maximum certainty. For nonpregnant women, excision is complemented by endocervical curettage. Choice of excision modality should favor an intact specimen with the most interpretable margins. Cold-knife conization is thus favored by many, but guidelines do not explicitly favor it over LEEP. If used, loop excision should be large enough to obviate the need for a second, deeper pass and should minimize cautery artifact. If there is no invasive cancer in the excision specimen, simple hysterectomy is recommended in women who have completed childbearing.

Women with AIS who strongly desire fertility preservation can be managed conservatively after an excision procedure. Individuals are counseled regarding the significant ongoing risk even with negative excision margins and endocervical sampling. The risk of residual AIS is reported to be as high as 80 percent in patients with positive margins (Krivak, 2001). Accordingly, repeat excision is advisable if hysterectomy is not planned. Close, long-term surveillance is recommended until hysterectomy is performed (Massad, 2013).

Postcolposcopy Surveillance without Treatment

When colposcopy fails to reveal high-grade CIN or there is spontaneous regression of high-grade CIN in young women, further surveillance is indicated given the significant false-negative rate of colposcopy and an increased risk of developing CIN in the future. This involves repeat cytology, HPV testing, or colposcopy alone or in combination depending on the original abnormal cytology result and age of the patient. Early surveillance generally is either cytology or cotest once or twice at 1-year intervals. Return to routine screening or an additional cotest generally occurs 3 years later. Exceptions are AGC, favor neoplasia and AIS Pap test results. These are always followed by excision unless invasive cancer is diagnosed during initial colposcopic examination and biopsy.

Current treatment of CIN is limited to ablation or excision procedures encompassing the entire TZ. Unlike ablation, excision provides a histologic specimen for evaluation of excised margins and further assurance that invasive cancer is not present. Any treatment should reach a depth of 5 to 7 mm from the surface to treat CIN adequately. Excess depth is avoided to minimize potential adverse consequences. Treatment using topical agents or therapeutic vaccines remains investigational. Selection of treatment modality is individualized. Salient factors include patient age, parity, size and severity of lesions, cervix contour, prior CIN treatment, and coexisting medical conditions. Treatment selection also depends on an operator’s experience and available equipment. No clear evidence shows any treatment technique to be superior, and surgical treatments have an approximate 90-percent success rate (Martin-Hirsch, 2013). A review of clinical considerations is provided by Khan and Smith-McKune (2014).

Ablation

In general, ablation of the TZ is effective for noninvasive ectocervical disease. Before ablation, evidence of glandular neoplasia or invasive cancer is excluded with the greatest certainty possible. Namely, cytology, histology, and colposcopic impression should be concordant; colposcopic examination must be adequate; and endocervical sampling should be negative for high-grade or ungraded CIN. Ablation should not be used after prior therapy, for an unexplained glandular cytologic abnormality, or for AIS. The most commonly used ablative treatment modalities are cryosurgery and carbon dioxide (CO₂) laser, and both techniques are illustrated in the atlas (Chap. 43). Before the introduction of LEEP, when cold knife conization was the only excision option, these ablative techniques were used more commonly. The relative decreased morbidity and ease of performing loop excision compared with cold knife conization and the trends toward observation of CIN 1 and of some CIN 2 and CIN 2/3 lesions in young women has led to decreased use of ablative procedures.

Cryosurgery is an ablative method that delivers a refrigerant gas, usually nitrous oxide, to a metal probe that freezes tissue on contact. Cryonecrosis is achieved by crystallizing intracellular water. This treatment is most appropriate for lesions and TZ lying entirely on the ectocervix, for a smooth cervical surface without deep crevices, and for CIN limited to two quadrants of the cervix (Table 29-7). Cryosurgery is generally not favored for the treatment of CIN 3 due to higher rates of disease persistence following treatment and lack of a histologic specimen to exclude occult invasive cancer (Martin-Hirsch, 2013). Moreover, cryosurgery and other ablative techniques are not favored for HIV-positive women with CIN due to higher failure rates (Spitzer, 1999). Less evidence suggests subsequent adverse effects on pregnancy outcome with cryotherapy than with loop excision. Thus, cryotherapy may be underused (Khan, 2014).

CO₂ laser is another ablative option and is delivered using colposcopic guidance with a micromanipulator. Cervical tissue is vaporized to a depth of 5 to 7 mm. Laser ablation is appropriate for CIN lesions associated with an adequate colposcopic examination. It is well suited for large, irregularly shaped CIN lesions of all grades and for condylomatous and preinvasive lesions at other LGT sites. If the cervical lesion extends onto the vagina, laser ablation may help customize removal of the entire lesion with favorable depth control. Laser ablation can also be augmented by laser or loop excision of central tissue for cases in which an ectocervical lesion extends into the endocervical canal or in which colposcopy is inadequate (American College of Obstetricians and Gynecologists, 2013).

Excision

Clinical scenarios with the highest risk of occult invasive cancer but without definitive histologic confirmation are evaluated further with an excision procedure. These include high-grade cytologic abnormalities with discordant (negative or low-grade) biopsy results or with inadequate colposcopy; AGC, favor neoplasia or AIS cytology; AIS histology; and endocervical sampling indicating ungraded or high-grade CIN or glandular neoplasia. With glandular cytologic abnormalities or AIS, an excisional modality that provides an intact specimen with the most interpretable margins should be chosen (Massad, 2013). Excision is indicated for recurrence of high-grade CIN after treatment due to the increased risk for occult invasive cancer (Paraskevaidis, 1991). Diagnostic excision refers to situations in which invasive cancer has not been excluded by the criteria needed before an ablation is performed. A therapeutic excision refers to one performed when these criteria have been met.

Excisional treatment modalities include LEEP, cold-knife conization (CKC), and laser conization, which are all illustrated in the atlas. Excisional procedures are associated with operative and long-term risks that include subsequent cervical stenosis and adverse pregnancy outcomes. For decades, CKC has been associated with cervical incompetence and preterm birth. The relationship between preterm birth and LEEP remains uncertain. Although some studies show LEEP to be an independent risk factor for preterm birth and premature rupture of membranes, others do not (Jakobsson, 2009; Kyrgiou, 2006; Sadler, 2004; Samson, 2005; Werner, 2010). An important confounder is the increased risk of preterm birth in women with cervical neoplasia compared with the general population even if they have not undergone an excisional procedure (Bruinsma, 2007; Conner, 2014; Shanbhag, 2009). This indicates that CIN and preterm birth have overlapping risk factors, making the contribution of treatment to this risk difficult to ascertain and controversial.

Of options, LEEP uses a thin wire on an insulated handle through which an electrical current is passed. This creates an instrument that can simultaneously cut and coagulate tissue, ideally during direct colposcopic visualization. Because LEEP can be performed using local anesthesia, it has become the primary outpatient treatment modality for high-grade cervical lesions, including those that extend into the endocervical canal (Table 29-8). LEEP provides a tissue specimen with margins that can be histologically assessed. Additionally, the size and shape of tissue excision can be customized by varying loop sizes and the order in which loops are used. This helps conserve cervical stroma volume.

Cold-knife conization is surgery that uses sharp excision to remove the cervical TZ and CIN lesion. It is performed in an operating room under general or regional anesthesia (Table 29-9). CKC is often preferred to LEEP for patients at highest risk for invasive cancer. These indications include cervical cytology suspicious for invasive cancer, patients older than 35 with CIN 3 or CIS, large high-grade lesions, and glandular neoplasia.

CO₂ laser conization allows precise tailoring of the cone shape to minimize stromal excision and yields less blood loss. Disadvantages are its expense, some thermal compromise of specimen margins, and special training requirements. This procedure can be performed under local, regional, or general anesthesia.

Surveillance after Treatment

Additional surveillance is required to assess treatment success (American College of Obstetricians and Gynecologists, 2013; Massad, 2013). Patients who have undergone a cervical excision with margins negative for HSIL or who have undergone an ablative procedure may be followed with cotesting 1 year later or serial cotesting at 12 and 24 months depending on whether the original abnormal cytology or biopsies showed low- or high-grade changes. Additional cytology or cotesting again at 3 years is recommended before returning to routine screening. After treatment of HSIL, routine screening should continue for at least 20 years due to a persistently increased risk of cervical neoplasia, even if screening extends beyond age 65.

If excision margins or endocervical curettage performed immediately after an excision are positive for CIN 2 or CIN 3, then surveillance with repeat cytology and endocervical sampling 4 to 6 months later is preferred. Repeat excision is acceptable. Repeat diagnostic excision is indicated for special circumstances such as AIS or microinvasive carcinoma at the excision margins.

Hysterectomy

Hysterectomy is unacceptable as primary therapy for CIN (American College of Obstetricians and Gynecologists, 2013; Massad, 2013). However, it may be considered when treating recurrent high-grade cervical disease if childbearing has been completed or when a repeat cervical excision is strongly indicated but not technically feasible. Although hysterectomy provides the lowest CIN recurrence rate, invasive cancer must always be excluded beforehand. The choice of either a vaginal or abdominal approach is directed by other clinical factors. Hysterectomy is the preferred treatment of AIS when future fertility is not desired.

Even with negative cervical margins, hysterectomy performed for CIN 2 or worse is not completely protective. Patients, particularly those who are immunosuppressed, are at risk for recurrent disease and require postoperative interval cytologic screening of the vaginal cuff as described on page 635.

Pathophysiology

Vaginal cancer is a rare malignancy comprising only 1 to 2 percent of gynecologic cancers. Nearly 50 percent of cases are diagnosed in women aged 70 years and older (Kosary, 2007). Approximately 90 percent of vaginal cancers are squamous cell carcinomas. These appear to develop slowly from precancerous epithelial changes, called vaginal intraepithelial neoplasia (VaIN), in a fashion similar to cervical cancer from CIN.

VaIN demonstrates histopathology similar to CIN and VIN. It is rarely found as a primary lesion and most often develops as an extension of CIN, mainly in the upper third of the vagina (Diakomanolis, 2002; Hoffman, 1992a). Unlike the cervix, the vagina lacks a TZ susceptible to HPV-induced neoplasia. However, HPV may gain entry from vaginal mucosal abrasions and reparative metaplastic squamous cell activity (Woodruff, 1981). In one review, investigators found HPV DNA in up to 98 percent of VaIN lesions and in three quarters of vaginal cancers. HPV 16 is the most common type (Alemany, 2014). Thus, HPV vaccination against HPV types 16 and 18 has the potential to also prevent vaginal cancers (Smith, 2009).

The natural history of VaIN is less understood than that of CIN, although their similar risk factors suggest a similar etiology. Cervical and vulvar neoplasia increase the risk for VaIN and vaginal squamous cancer. Women treated for CIN 3 are at increased risk of developing both cervical and vaginal cancers, and this risk accelerates in those older than 60 (Strander, 2014). Moreover, a retrospective study suggests that hysterectomy is not definitive therapy for high-grade neoplasia, as researchers have found a subsequent high-grade VaIN recurrence rate greater than 7 percent (Schockaert, 2008).

Diagnosis

Generally, VaIN is asymptomatic. If present, symptoms may include spotting, discharge, and odor. Abnormal cytology is often the first indication of VaIN. Subsequent examination of the vagina with a colposcope, termed vaginoscopy, frequently identifies a lesion for biopsy. Prior to visual evaluation, careful palpation of the vagina is advisable, particularly if the patient has undergone hysterectomy for high-grade cervical neoplasia. In such cases, invasive cancer may present as a nodular lesion buried within the vaginal cuff before it becomes visible.

During vaginoscopy, inspecting the entire vagina using a colposcope can be challenging because of a large surface area, rugation, and surfaces parallel to the colposcope’s visual axis. Particular attention is paid to the upper third of the vagina due to the common etiology of VaIN as an extension of CIN. After hysterectomy for high-grade CIN, abnormal vaginal cytology should prompt careful inspection of the vaginal cuff. By applying 3- to 5-percent acetic acid to the vaginal mucosa, aceto­white changes consistent with HPV infection or neoplasia are identified (Fig. 29-17). Vascular patterns are less common in VaIN lesions than with CIN, but coarse punctation and even atypical vessels may be seen in high-grade and invasive lesions. High-grade VaIN tends to demonstrate flat, dense acetowhitening with sharply demarcated borders. Half-strength Lugol solution applied to the vagina further delineates abnormal areas. Similar to cervical dysplasia, strongly nonstaining areas most likely contain abnormal epithelium. Iodine staining aids biopsy site selection, and areas with the least staining and straightest lesion margins are preferred. Biopsy may be obtained by means of a cervical biopsy forceps, and an Emmett hook can be used to elevate and stabilize vaginal tissue if needed. Local anesthesia is usually not necessary for biopsies of the upper third of the vagina but may be needed for more distal biopsies. The vaginal tissue is grasped and lifted to limit the biopsy depth. Menopausal women may have significant thinning of the vaginal mucosa, and biopsy is done with greater care or with a smaller biopsy forceps to avoid perforation of the vaginal wall. Hemostasis is achieved using silver nitrate applicators or Monsel paste. Vaginal lesion size, location, and specific biopsy sites are carefully documented for future management and surveillance.

Management

Like high-grade CIN, high-grade VaIN is believed to be a precancerous lesion and generally warrants eradication (Punnonen, 1989; Rome, 2000). Because vaginal neoplasia is uncommon, most management strategies are derived from small, retrospective, and statistically underpowered studies. Management of VaIN depends on the grade of neoplasia and may include observation, excision, ablation, topical antineoplastics, or rarely, radiation therapy. Each treatment method has advantages and disadvantages, and none has proven superior efficacy. Management strategies are determined by lesion size, number, and location; histologic diagnosis; and comprehensive patient counseling.

Low-Grade VaIN

In a long-term study of 132 patients with VaIN, Rome and associates (2000) found that an observational approach after biopsy resulted in VaIN 1 regression in seven of eight patients (88 percent). No VaIN 1 lesion progressed to high-grade VaIN or invasive cancer. Vaginal LSIL often represents atrophy or a transient HPV infection. Spontaneous regression is common, and observation is preferable in most cases. Aggressive treatment is avoided. Although no evidence-based guidelines are available, surveillance similar to that for low-grade CIN with repeat cytology with or without vaginoscopy every 6 to 12 months seems reasonable until abnormalities resolve or progress to HSIL.

High-grade VaIN

Observation of VaIN 2 may be considered in selected patients, but the safety of this approach is not established. Treatment choice for patients with high-grade VaIN is influenced by several factors including the location and number of lesions, the patient’s sexual activity status, vaginal length, prior radiation therapy, previous treatment modalities in patients with recurrent VaIN, and clinician experience. Potential adverse effects of treatment on subsequent quality of life such as pain, difficulties with sexual intercourse, and scarring are always considered when choosing a therapeutic modality.

Wide local excision of a high-grade unifocal lesion or partial vaginectomy for multifocal lesions may be used. Hoffman (1992a) found that nine of 32 patients (28 percent) with prior hysterectomy and VaIN 3 had occult invasive cancer in the vaginal cuff. Therefore, surgical excision is considered for high-grade lesions involving the vaginal cuff, particularly if any thickening or nodularity of vaginal apex suggests occult invasive disease. Excisional procedures have the advantage of providing a surgical specimen for which resected-margin status can be determined and the presence of invasive vaginal cancer excluded. Partial vaginectomy is surgically challenging but has the highest cure rate and fewest recurrences for high-grade disease (Dodge, 2001). Wide local excision carries less morbidity than vaginectomy, but both procedures may be complicated by bladder or rectal injury and hemorrhage. In addition, subsequent vaginal scarring and stenosis may compromise vaginal intercourse or cause dyspareunia. Sharp dissection is favored for local excision and for partial vaginectomy. Laser causes significant thermal damage to the tissue specimen and generally is not recommended for excision of vaginal mucosa. Loop excision has poor depth control and carries a substantial risk of thermal damage to underlying pelvic structures, including the bladder and bowel. LEEP should not be used for vaginal surgery.

CO ₂ laser ablation is an option for lesions not concerning for invasive disease. It is well suited for eradication of multifocal lesions and causes less scarring and blood loss than tissue excision. Rarely, excessive bleeding and thermal damage to the bladder and bowel can occur. In one study, investigators monitored 21 patients after high-grade VaIN CO₂ laser ablation and found that 14 percent had persistent disease requiring retreatment. One patient progressed to invasive carcinoma, which underscores the importance of long-term surveillance (Perrotta, 2013). A broader explanation of laser ablation techniques is found in Section 43-26.

Topical therapy, as with ablative procedures, is suitable if there is no suspicion of invasive disease by cytology, vaginoscopy, or histology. Persistent VaIN 2 and selected VaIN 3 lesions may be medically treated using 5-percent fluorouracil (5-FU) cream “off-label,” as it is not FDA approved for this specific indication (Krebs, 1989). Its efficacy is unproven in large, randomized trials, and studies with small numbers of patients have demonstrated mixed results. Treatment regimens vary widely. One dosing schedule calls for a 3-mL dose of cream placed in the vaginal vault by plastic vaginal applicator every other day for 3 days during the first week of treatment and once weekly thereafter for up to 10 weeks. 5-FU cream is often associated with a robust inflammatory reaction that can include vaginal burning and vulvar irritation. To minimize leakage onto the vulva, it is best applied intravaginally at bedtime, when a recumbent position will be maintained for hours. Additionally, an occlusive, water-resistant ointment can be used to protect the vulva. Protective gloves are worn when handling 5-FU cream, and measures are taken to avoid 5-FU contact by sexual partners. Patients selected for this treatment require thorough counseling, effective contraception as needed, consent for off-label medication use, and close monitoring for excessive inflammation and ulceration, which can lead to vaginal or vulvar scarring and loss of function.

Radiation therapy has a very limited role for treatment of high-grade VaIN. It carries a significant risk of serious morbidity and is reserved for select cases. In a review of 136 cases of vaginal carcinoma in situ, radiation therapy was used in 27 patients, and a 100-percent cure rate was noted. However, 63 percent developed significant complications including vaginal stenosis, adhesions, ulceration, necrosis, and fistula formation (Benedet, 1984). Furthermore, radiation treatment compromises subsequent cytologic, colposcopic, and histologic interpretation. Disease recurrence often necessitates radical surgery.

Prognosis

In a study of 132 patients treated for high-grade VaIN, excision and CO₂ laser ablation had similar cure rates of 69 percent. Topical 5-FU cream was curative in 46 percent of cases (Rome, 2000). Patients with any grade of vaginal neoplasia require long-term monitoring, as the persistence and recurrence rate for high-grade disease is significant. Currently, no evidence-based guidelines are available for posttreatment surveillance of VaIN. Monitoring includes collection of vaginal cytology and performance of vaginoscopy approximately 2 to 4 months after treatment is completed. Continued surveillance with periodic cytology with or without vaginoscopy at 6- to 12-month intervals for several years thereafter seems prudent. Long-term cytologic screening is needed thereafter.

Pathophysiology

Vulvar cancer is rare. In 2015, vulvar cancer made up less than 5 percent of all gynecologic cancers and less than 0.6 percent of all cancers in the U.S. women (American Cancer Society, 2015). Ninety percent of vulvar cancer is squamous and in some cases may develop slowly from VIN (Fig. 29-18) (Judson, 2006). However, compared with CIN, VIN less often progresses to high-grade disease and cancer. The incidence of vulvar carcinoma in situ has increased significantly over the past several decades. This trend is particularly pronounced in younger women and is thought to be linked to the increased incidence of STDs, including HPV (Howe, 2001). Jones and coworkers (2005) reported that the mean age of women with VIN has decreased from 50 to 39 years since 1980.

Although HPV DNA has been found in up to 80 percent of VIN lesions, HPV is less commonly associated with vulvar cancers, and rates range between 15 and 80 percent (Del Pino, 2013). The progression of vulvar carcinoma in situ to invasive cancer has been strongly suggested, although not confirmed conclusively. Therefore, VIN 3 lesions are generally treated (van Seters, 2005).

Classification

Terminology for squamous VIN was introduced by the International Society for the Study of Vulvar Disease (ISSVD) in 1986. Under this classification, VIN grades 1, 2, and 3 were defined by abnormal cellular changes found to varying thicknesses within the squamous epithelium, similar to CIN (Wilkinson, 1986). In 2004, classification of VIN was simplified by the ISSVD (Sideri, 2005). The older designation of VIN 1 has been eliminated, whereas VIN 2 and 3 categories have been combined. This redefinition reflects whether lesions are likely to be premalignant and thus whether lesions require therapy. The VIN 1 category was eliminated because evidence is lacking that such lesions are cancer precursors. These lesions likely represent benign reactive changes or HPV effect usually caused by low-risk HPV types 6 and 11 (Smith, 2009; Srodon, 2006). Since the histologic distinction between VIN 2 and VIN 3 is not reliably reproducible, they are now combined under the term VIN (Table 29-10). Most recently, use of LSIL and HSIL terminology similar to other anogenital sites has been recommended for vulvar lesions (Darragh, 2012).

VIN is now categorized as usual type (uVIN), differentiated type (dVIN), or unclassified type. Of these, uVIN encompasses most former VIN 2, VIN 3, and vulvar CIS lesions. uVIN lesions can be subcategorized histologically as warty (condylomatous), basaloid, or mixed and are associated with oncogenic HPV infection. HPV 16 is the most prevalent HPV type found in VIN 2/3 and vulvar cancer (Smith, 2009). In general, HPV-related high-grade VIN lesions histologically resemble high-grade CIN and tend to be multicentric (Feng, 2005; Haefner, 1995).

The entire lower genital tract is vulnerable to HPV infection. Therefore, risk factors for uVIN are similar to those for VaIN and CIN. Accordingly, uVIN risk is strongly associated with multiple sexual partners, STDs, and tobacco smoking, particularly in younger women (Hoffman, 1992b; Jones, 2005). It is also seen as part of multifocal LGT neoplasia in immune compromised women.

In contrast, dVIN is less common and accounts for only 2 to 10 percent of all VIN cases (Hart, 2001). Such lesions tend to be unifocal and are typically found in older, nonsmoking, postmenopausal women in their sixth and seventh decade. Infection with oncogenic HPV is uncommon and probably does not play a role in the genesis of these lesions. Instead, they tend to be associated with chronic inflammatory skin conditions or p53 inactivation mutations (Del Pino, 2013). However, dVIN is more likely to progress to squamous cell carcinoma than uVIN. One study noted that progression of dVIN to vulvar squamous cell carcinoma was five times higher than for uVIN (van de Nieuwenhof, 2009). The pathologic diagnosis of dVIN is difficult and interobserver agreement is low. If clinical findings warrant, review by an experienced gynecologic pathologist may be helpful (van den Einden, 2013).

Rare pagetoid types of VIN 2 and 3 cannot be classified in any of the foregoing categories. These are termed VIN, unclassified type (Sideri, 2005).

Diagnosis

Clinical Findings

VIN may be asymptomatic and discovered with routine gynecologic examinations or during evaluation of abnormal cervical or vaginal cytology. When present, signs and symptoms (itching, burning, pain) may affect a patient’s sexual functioning and quality of life. Whereas high-grade lesions of the cervix and vagina are generally invisible without acetic acid application and use of a colposcope, clinically significant VIN lesions are usually visible without the aid of special techniques. Lesions vary widely in appearance but are usually sharply demarcated (Del Pino, 2013). They may be white, hyperkeratotic plaques; hyperpigmented lesions; or areas of erythema. Lesions may be raised or flat. uVIN is associated with HPV-related lesions or neoplasia elsewhere in the anogenital tract. Often, lesions appear bulky, resemble condylomata, and are multifocal with extensive involvement of the perineum and adjacent skin (Fig. 29-19). dVIN is generally unifocal and may be associated with lichen sclerosus or lichen simplex chronicus of the adjacent skin. A lesion may appear as an ulcer, warty papule, or hyperkeratotic plaque.

To avoid diagnostic delay, most focal vulvar lesions are biopsied, particularly lesions that are irregularly or darkly pigmented, asymmetric, large, elevated, roughened, nodular, or ulcerated. Ulceration, surrounding induration, or inguinal adenopathy raises suspicion for invasive cancer. Other scenarios suspicious for VIN include enlarging lesions, warty lesions in postmenopausal or immune compromised women, and warts that are atypical in appearance or persist despite topical therapies (American College of Obstetricians and Gynecologists, 2014b).

Vulvoscopy

Histologic confirmation is necessary before high-grade VIN is managed. Selection of the best location to biopsy is aided by magnification of the vulva, perineum, and perianal skin, usually with a colposcope. This examination is termed vulvoscopy. Alternatively, any good light source and a handheld magnifying lens can be used.

Vulvar epithelial changes are enhanced by applying a 3- to 5-percent acetic-acid-soaked gauze pad to the vulva for 5 minutes prior to examination. This is usually well tolerated but may cause pain or burning in the presence of vulvar irritation, ulceration, or fissures. Acetic acid accentuates the surface topography of lesions and may reveal acetowhite lesions not seen grossly. Pigmented VIN lesions tend to turn a dusky gray due to hyperkeratosis. Vascular patterns are generally not seen, but high-grade VIN rarely may demonstrate coarse punctation. Normal vulvar tissue, particularly the inner, posterior labia minora, may turn diffusely acetowhite and should not be treated based on this appearance.

As an alternative, 1-percent toluidine blue, a nuclear stain, may help define the best site for biopsy or for surgery margins (Joura, 1998). Its use is technically more challenging, and results are fraught with both false positives and false negatives. Therefore, its use has been largely abandoned.

The most abnormal-appearing areas are biopsied, although necrotic areas often yield nondiagnostic findings and are avoided if possible. Biopsies measuring up to 6 mm in diameter can be obtained using a Keyes punch after provision of a local anesthetic injection (Fig. 4-2). Topical anesthetics can be applied several minutes prior to injection of local anesthesia to decrease discomfort. If lesions are close to the clitoral hood, general anesthesia is often warranted due to increased pain with injection of local anesthesia and increased vascularity. Biopsy sites measuring 4 mm or greater occasionally require suturing for hemostasis or cosmetic closure, especially on mucosal surfaces that stretch.

Management

VIN 1

As noted, the progression of VIN 1 to VIN 3 has not been established, and the VIN 1 category has been eliminated entirely. Thus, lesions reported as VIN 1 are not treated, but instead reassessed annually in patients at risk for high-grade VIN. Reassessment may include gross inspection or vulvoscopy and biopsy as clinically indicated if high-grade neoplasia is suspected.

VIN 2 and 3

With rare exception, high-grade VIN is treated (American College of Obstetricians and Gynecologists, 2014b). Standard treatment of high-grade lesions of the vulva consists of local destruction or excision. Medical management is currently limited (Pepas, 2011). VIN involving the hair-bearing areas of the vulva (external to Hart line) may extend deeper into pilosebaceous units, whereas mucosal lesions tend to be more superficial (Wright, 1992). VIN involves the pilosebaceous units in up to two thirds of cases, but rarely exceeds 2.5 mm in depth from the epidermal surface (Shatz, 1989). This is important for disease management, particularly if ablative procedures are considered. Regardless of the modality selected, treatment side effects are common and can include vulvar discomfort, poor wound healing, infection, and scarring that may result in chronic pain or dyspareunia. Thus, treatment objectives include: (1) improving patient symptoms, (2) preserving the appearance and function of the vulva, and (3) excluding and preventing invasive disease.

Wide local excision (WLE) with a surgical margin of at least 5 mm of normal tissue is preferred for large VIN lesions in which the possibility of invasive carcinoma cannot be excluded. Because disease recurrence is related to surgical margin status, frozen section histology of the specimen margins is advantageous (Friedrich, 1980; Jones, 2005). Hopkins (2001) reported disease recurrence rates of 20 percent for cases with negative surgical margins but 40 percent for those with positive margins. WLE can be disfiguring and may require plastic surgical techniques or skin grafting to minimize anatomic distortion, pain, and loss of function. Moreover, due to disease location, some patients are best treated by combined excisional and ablative procedures.

Laser ablation of VIN provides good cosmetic results, and the depth of tissue destruction can be adjusted for hair-bearing areas. However, CO₂ lesion ablation does not allow evaluation of a surgical specimen. Therefore, invasive carcinoma must be excluded beforehand by adequate biopsy. Laser is generally less disfiguring than WLE but can result in prolonged, painful healing. Preoperative counseling regarding anticipated postoperative results mirrors that for WLE. VIN recurrence has been reported more commonly following laser vaporization than after WLE (Herod, 1996). However, Hoffman (1992b) reported that 15 of 18 patients (83 percent) with VIN 3 remained free of recurrent disease after CO₂ laser ablation.

Cavitational ultrasonic surgical aspiration (CUSA) may be used to treat VIN confined solely to non-hair-bearing vulvar skin. Ultrasound is used to cause cavitation and disruption of affected tissue, which is then aspirated and collected (Section 43-28). CUSA offers the advantages of laser, less scarring and pain than WLE, while additionally providing a pathologic specimen (von Gruenigen, 2007). However, the tissue specimen is fragmented and lacks the diagnostic accuracy of surgically excised tissue. Miller (2002) evaluated CUSA in 37 patients with VIN 2/3. They found an overall recurrence rate of 35 percent within a mean of 33 months.

Topical therapy can be considered if there is no concern for invasive cancer, the patient is able to self-administer the topical medication correctly, and the importance of compliance to follow-up is understood. No topical agent is FDA-approved specifically for the treatment of VIN. Cidofovir cream must be compounded. 5-FU is potentially caustic and teratogenic and is not a first-line choice for VIN treatment (National Cancer Institute, 2015b). The clinical efficacy of these two agents has not been demonstrated in clinical trials, and they are generally no longer used (American College of Obstetricians and Gynecologists, 2014b). Topical imiquimod (off-label) has garnered the most interest. It has lower toxicity, and numerous studies including two randomized controlled trials have reported favorable regression rates of high-grade VIN (Mahto, 2010; van Seters, 2008). A phase II study on the use of imiquimod in treating VIN 2/3 found a response rate of 77 percent and 20 percent recurrence rate compared with a recurrence rate of 53 percent in a surgically treated cohort (Le, 2007). The use of topical imiquimod for the treatment of lower genital tract neoplasia was recently reviewed by de Witte and colleagues (2015).

Prognosis and Prevention

Case reports exist describing the invasive potential of untreated, high-grade VIN (Jones, 2005). Jones and associates (1994) reviewed the outcome of 113 patients with VIN 3. They found that 87 percent of untreated patients progressed to vulvar cancer, whereas only 3.8 percent of treated patients progressed to invasive carcinoma. It is currently not possible to predict high-grade VIN lesion behavior. Regardless of the treatment modality chosen, recurrence is common (up to 50 percent), particularly in patients with multifocal disease or immune compromise. Indefinite surveillance for multifocal LGT disease is recommended. Moreover, some consider high-grade VIN to be an indication for colposcopic evaluation of the cervix and vagina regardless of normal cervical cytology. Posttreatment surveillance consists of careful vulvar reevaluation at 6 and 12 months and annual vulvar inspection thereafter (American College of Obstetricians and Gynecologists, 2014b).

For prevention, prophylactic HPV vaccination against types 16 and 18 has the potential to prevent approximately one third of vulvar cancers (Smith, 2009). Smoking cessation and optimization of compromised immune status are also important strategies.

Pathophysiology

In 2015, 4630 new anal cancers and 610 anal cancer deaths are predicted for U.S. women, and this cancer’s incidence and mortality rates have risen since 1975 (American Cancer Society, 2015). Anal cancer is strongly associated with anal intraepithelial neoplasia (AIN) (Palefsky, 1994). Studies also continue to suggest an association between high-risk cervical HPV infection, abnormal anal cytology, and anal cancer (Lamme, 2014; Sehnal, 2014; Valari, 2011). Santoso and associates (2010) reported a 12-percent prevalence of biopsy-proven AIN in a group of women with HPV-related disease. As with cervical cancers, HPV types 16 and 18 are the principal etiologic agents (Zbar, 2002).

Little is known of the natural history of anal HPV infection and its progressive potential in women, but it is suspected to behave similarly to cervicovaginal lesions. Cervical and anal lesions generally are manifested at or near their respective squamocolumnar epithelial junctions, which is called the transition zone in the anal canal (Goldstone, 2001). Anal disease is classified by the same cytologic and histologic nomenclature used to describe cervical disease. Thus, AIN 1, 2, and 3 correspond to mild, moderate, and severe dysplasia, respectively (Fig. 29-20). The newer nomenclature for squamous neoplasia throughout the anogenital tract replaces AIN 1 with anal LSIL, and AIN 2/3 with anal HSIL (Darragh, 2012).

Risk factors for AIN include anal HPV infection, receptive anal intercourse, tobacco smoking, and history of other STDs, including HIV. Anal cancer and its likely precursor, AIN 3, are increasing at higher rates in the HIV-positive compared with the HIV-negative population (Heard, 2015; Tandon, 2010).

Diagnosis

Currently, neither the American College of Obstetricians and Gynecologists nor the USPSTF provides screening recommendations for AIN in women. Potential approaches include periodic testing with anal cytology, HPV testing, or anoscopy, or a combination of these. Some suggest that annual cervical and anal cytology should be offered to all HIV-positive women, but only if the infrastructure necessary to evaluate and manage abnormal cytology results and precancerous lesions is available (Palefsky, 2005; Panther, 2005). For the generalist, patients may be referred to tertiary care centers or colorectal surgeons.

Anal cytology as a screening test has uncertain efficacy for AIN and anal cancer (Nahas, 2009; Santoso, 2010). If used, anal cytology may be more sensitive using liquid-based preparations than conventional glass slides (Friedlander, 2004; Sherman, 1995). Sampling is obtained by inserting a Dacron swab or endocervical brush moistened with water or a small amount of water-based lubricant approximately 5 cm into the anal canal, presumed above the anal transformation zone. The device is then withdrawn with a twirling motion while applying lateral pressure to the anal canal walls. The swab is then either swirled in the cytology solution to release exfoliated cells or smeared on a glass slide and fixed with isopropyl alcohol as with cervical cytology. Nothing per rectum is recommended 24 hours prior to an anal cytology test. Anal cytology may be reported using terminology analogous to the Bethesda 2001 nomenclature for cervical cytology.

High-resolution anoscopy uses illumination and magnification provided by a colposcope. Anoscopy is more challenging to perform than colposcopy for both patient and the provider, and special training is recommended. Acetic acid is applied to evaluate the anal canal in a manner similar to colposcopy (Fig. 29-21) (Jay, 1997). Anal neoplasia demonstrates colposcopic features similar to those of CIN, and analogous lesion grading and terminology are used. Biopsies are directed at the most abnormal areas. Some consider high-resolution anoscopy to be the gold standard for diagnosing AIN, but its role for primary screening or for the evaluation of abnormal anal cytology is not yet defined. It is presently available in a limited number of health centers.

Management

The benefits of screening for, identification of, and eradication of anal cancer precursor lesions are currently under investigation, and clinical guidelines are not yet unavailable. Some suggest that eradication of high-grade anal lesions may decrease the incidence of invasive anal cancer (Santoso, 2010). However, in contrast to cervical neoplasia, the protective effect of treating precursor lesions of the anal canal remains unproven (Williams, 1994; Scholefield, 2005). Thus, decisions regarding screening for and managing AIN should be shared by provider and patient on an individual basis. Abnormal anal cytology is best evaluated with high-resolution anoscopy. High-grade AIN lesions are referred to appropriate specialists for possible excision or ablative procedures.

Treatment is restricted to locally ablative or excisional procedures that eliminate individual high-grade intraepithelial lesions. Unlike the cervix, the entire anal squamocolumnar junction cannot be destroyed or removed due to potential morbidity. Biopsy-proven high-grade AIN lesions can be ablated using CO₂ laser or electrosurgical coagulation performed under general anesthesia, or infrared coagulation as an office procedure (Chang, 2002; Goldstone, 2005). Cryoablation and topically applied 85-percent trichloroacetic acid are other alternatives. Finally, as prevention, the FDA (2010) has approved both the quadrivalent (Gardasil) and nonavalent HPV (Gardasil 9) vaccines for the prevention of anal cancer and precancerous lesions associated with HPV types 6, 11, 16, and 18 in both males and females.

HIV-infected women have a high burden of HPV-associated anogenital disease. In this population, up to 60 percent of Pap tests are abnormal, and up to 40 percent have colposcopic evidence of dysplasia. Compared with rates in HIV-uninfected women, HIV-infected women show higher rates of both CIN and VIN (Ellerbrock, 2000; Spitzer, 1999; Wright, 1994). Moreover, abnormal cervical cytology and/or cervical HPV results increase risks for anal HPV infection and anal neoplasia (Tandon, 2010; Heard, 2015). The risks of all HPV-associated cancers of the vulva, vagina, and anus appear to increase during the period from 5 years before to 5 years after HIV seroconversion (Chaturvedi, 2009).

HIV infection influences LGT disease prognosis. For example, during the early years of the acquired immunodeficiency disease (AIDS) epidemic, Maiman and colleagues (1990) observed 100-percent mortality rates in HIV-positive women with cervical cancer compared with only 37 percent of HIV-negative women in a study cohort. Because of the increased risk of cervical cancer and poorer prognosis, cervical cancer was designated as an AIDS-defining condition. Fortunately, HIV-infected women who receive regular screening and recommended follow-up for CIN experience the same incidence of invasive cervical cancer as do HIV-negative women (Massad, 2009).

Because of a significantly higher risk of developing SIL, cervical cytologic screening is obtained every 6 months for the first year after an HIV infection diagnosis (Centers for Disease Control and Prevention, 2015). Thereafter, indefinite annual screening is recommended (American College of Obstetricians and Gynecologists, 2012a; Kaplan, 2009). In addition, women with HIV may benefit from anal Pap screening (Palefsky, 2001). However, evidence-based screening recommendations for AIN and anal cancer are not yet available. Women with HIV infection are routinely questioned about anorectal symptoms such as pain or bleeding and provided periodic digital rectal examinations.

The 2012 Consensus Guidelines recommend that Pap test abnormalities, including ASC-US, in HIV-positive women be managed as in the general population (Massad, 2013). However, the Centers for Disease Control and Prevention has questioned the utility of HPV testing for the triage of ASC-US in this group and thus recommends that all HIV-positive women with ASC-US results be referred for colposcopy (Kaplan, 2009). Because HIV-positive women with CIN are often found to have extensive, multifocal dysplastic epithelial disease, any colposcopic examination includes inspection of the entire LGT (Hillemanns, 1996; Tandon, 2010).

HIV-positive women are at higher risk of disease persistence, recurrence, and progression after CIN or VIN treatment, and poorer outcomes appear to correlate with degree of immune suppression. Cryotherapy for CIN has a particularly high failure rate among treatment methods (Korn, 1996; Spitzer, 1999). Additionally, ablative modalities have an increased risk of obscuring occult invasive cancer in high-grade lesions. Cervical excisional procedures including loop excision and cold-knife conization provide histologic confirmation and margins for evaluation. Although excisional therapy is effective for eradicating CIN in immune competent patients, the same treatment may be effective only in preventing progression to cancer in HIV-infected women (Heard, 2005).

The therapeutic impact of highly active antiretroviral therapy (HAART) on HPV infection is poorly understood, and results are conflicting (Heard, 2004). To date, HAART has not been shown consistently to improve the natural history of HPV-related diseases. In fact, anal cancer rates in HIV-infected individuals have continued to increase over the past decade (De Vuyst, 2008; Tandon, 2010). Indeed, if HAART does not alter the incidence or progression of HPV-related disease, individuals on HAART may gain sufficient longevity to develop HPV-related epithelial cancers (de Sanjose, 2002).