Chapter 21-4: Bladder Cancer

TEXTBOOK PRESENTATION

Bladder cancer classically presents as painless visible (gross) hematuria in an older male smoker. However, episodes of gross hematuria may be intermittent, and thus asymptomatic nonvisible (microscopic) hematuria may be the only sign for some patients. If present, symptoms may include dysuria or obstructive symptoms.

DISEASE HIGHLIGHTS

1. Accounts for 90% of urothelial cancers

2. Visible painless hematuria, often intermittent, occurs in 85% of patients

3. Risk factors for bladder cancer

   1. Male sex and white race: bladder cancer is 3–4 times more likely to develop in white males than black males or white females

   2. Smoking: accounts for 60% of bladder cancers in males and 30% in females

   3. Age > 40 years: median age at diagnosis is 70 years

   4. Preexisting urothelial cancer (RCC, ureteral, prostate)

   5. History of pelvic radiation

   6. Chronic UTI

   7. Schistosomiasis (in Africa and the Middle East)

   8. Industrial chemical/toxin exposure

      1. Kidneys filter and concentrate metabolic toxins into the urine which pool in the bladder, promoting oncogenesis

      2. Accounts for about 20% of bladder cancers

      3. 10- to 20-year latency period between exposure and disease

      4. Compounds associated with bladder cancer include aromatic amines, aniline dyes, nitrates, nitrites, coal, and arsenic.

      5. Occupations associated with a higher risk of bladder cancer include miners, bus drivers, rubber workers, motor mechanics, leather workers, blacksmiths, machine setters, hairdressers, and mechanics.

4. Prognosis: 10-year survival for muscle-invasive cancer still confined to the bladder is 65–72%.

EVIDENCE-BASED DIAGNOSIS

1. The diagnostic approach is based on the estimated pretest probability of disease.

2. Prevalence of cancer in patients with hematuria

   1. Microscopic hematuria

      1. Up to 8.9% of patients had a malignancy in 1 series

      2. Another cohort found bladder cancer in 3.7%, RCC in 1%, and ureteral cancer in 0.2%.

      3. Malignancy was extremely rare in patients under the age of 40 with microscopic hematuria.

   2. Gross hematuria: studies generally included older patients who presented to “hematuria clinics”

      1. Consistently > 10% had a malignancy and in some studies, the prevalence was > 25%

      2. 20–25% had bladder cancer

      3. 1.3–10% had prostate cancer

      4. 0.6–2% had RCC

      5. 21% had stones

      6. 12–13% had BPH

   Urothelial cancer is a must not miss diagnosis in patients with gross hematuria not due to an infection.

3. White light flexible cystoscopy with biopsies is the gold standard for diagnosing bladder cancer; random biopsies of bladder tissue are taken to detect carcinoma in situ not visible to the naked eye.

4. Hexaminolevulinate fluorescence cystoscopy is also useful for detecting carcinoma in situ.

5. Multiphasic CT urography is done with and without contrast and includes imaging in the excretory phase.

   1. Has largely replaced other imaging modalities, such as IV pyelogram, ultrasonography, conventional CT, and retrograde pyelography to evaluate unexplained hematuria

   2. Comparatively higher sensitivity (92–100%) and specificity (94–97%) for the detection of renal masses, urinary tract stones, and genitourinary transitional cell carcinomas

   3. May improve the sensitivity of cystoscopy if done first

   4. Delivers a relatively high radiation dose; therefore, some guidelines recommend avoiding in low-risk patients

6. Ultrasound

   1. The sensitivity of ultrasound for bladder ...