Testicular and ovarian pathology focuses predominantly on neoplasms, although not all clinically important pathologic processes of these organs are neoplastic. The majority of testicular tumors are derived from germ cells, and the majority of ovarian tumors are derived from surface epithelial cells. Many germ cell tumors in the testes and in the ovaries share common features. One important pathologic process in both the penis and in the cervix is squamous cell carcinoma, caused by the human papillomavirus (HPV). In the prostate, there are basically three pathologic processes that are of most importance: acute prostatitis, benign prostatic hyperplasia, and prostatic adenocarcinoma. The breast hosts a multitude of histologic abnormalities, from fibrocystic disease to invasive ductal adenocarcinoma. With many of the benign lesions, their importance lies in their associated risk of later development of invasive carcinoma.
This chapter will discuss testicular tumors, squamous cell carcinoma of the penis, prostatic pathology (including benign prostatic hyperplasia and prostatic adenocarcinoma), tumors of the vagina, cervical intraepithelial neoplasia (CIN) as a precursor of squamous cell carcinoma of the cervix, amenorrhea, pelvic inflammatory disease, uterine pathology (including endometrial hyperplasia and endometrioid adenocarcinoma), ovarian pathology (including neoplasms), various disorders of pregnancy, and breast pathology (including non-neoplastic and neoplastic diseases).
Overview: All masses of the testes are considered malignant until proven otherwise. Approximately 95% of testicular tumors are derived from germ cells (Figure 17-1). Seminomas tend to remain localized in the testis for a longer period, are radiosensitive, and metastasize to lymph nodes, whereas nonseminomatous neoplasms metastasize sooner, are radioresistant, and tend to metastasize via hematogenous routes. The classic presentation of testicular cancer is a painless testicular mass.
Mixed germ cell tumor of testis. This testicle has been bisected (the spermatic cord is at the 12-o'clock position), revealing an expansive mass in the parenchyma. The mass has a variegated appearance, consistent with a mixed germ cell tumor.
Sites of metastases from testicular neoplasms
- Lymph nodes: Para-aortic, mediastinal, and supraclavicular lymph nodes.
- Hematogenous dissemination: Lungs, liver, brain, bone.
Two categories of testicular neoplasms
- Germ cell (most common type of testicular neoplasm).
- Non–germ cell (including sex cord–stromal tumors and Leydig cell tumors).
Risk factors for development of testicular neoplasms
- Cryptorchidism (i.e., undescended testicle).
- Syndromes with testicular dysgenesis (e.g., Klinefelter syndrome).
- Family history and history of a tumor in the contralateral testis.
World Health Organization (WHO) classification of testicular neoplasms
- Tumors with one histologic pattern.
- Tumors with more than one histologic pattern (also referred to as mixed germ cell tumor), which account for 60% of testicular tumors.
Mutations: Isochromosome (12p) is found in virtually all germ cell tumors. It encodes the DAD-R gene, which produces a protein that prevents apoptosis.