Bladder cancer
Bladder tumors can develop on the surface of the bladder wall (benign or malignant papillomas) or grow within the bladder wall (generally more virulent) and quickly invade underlying muscles. Most bladder tumors (90%) are transitional cell carcinomas, arising from the transitional epithelium of mucous membranes. Less common are adenocarcinomas, epidermoid carcinomas, squamous cell carcinomas, sarcomas, tumors in bladder diverticula, and carcinoma in situ. Bladder tumors are most prevalent in men older than age 50 and are more common in densely populated industrial areas, but
women are diagnosed at more advanced stages, (See Women and bladder cancer.)
women are diagnosed at more advanced stages, (See Women and bladder cancer.)
Causes
Certain environmental carcinogens—such as 2-naphthylamine, benzidine, tobacco, and nitrates—predispose people to transitional cell tumors. Thus, workers in certain industries (rubber workers, weavers, leather finishers, aniline dye workers, hairdressers, petroleum workers, and spray painters) are at high risk for such tumors. The period between exposure to the carcinogen and development of symptoms is about 18 years.
Squamous cell carcinoma of the bladder is most common in geographic areas where schistosomiasis is endemic. It’s also associated with chronic bladder irritation and infection (for example, from kidney stones, indwelling urinary catheters, and cystitis caused by cyclophosphamide).
Signs and symptoms
In early stages, about 25% of patients with bladder tumors have no symptoms. Commonly, the first sign is gross, painless, intermittent hematuria (often with clots in the urine). Patients with invasive lesions often have suprapubic pain after voiding. Other symptoms include bladder irritability, urinary frequency, nocturia, and dribbling.
Diagnosis
Only cystoscopy and a biopsy can confirm bladder cancer. Cystoscopy should be performed when hematuria first appears. When it’s performed under anesthesia, a bimanual examination is usually done to determine if the bladder is fixed to the pelvic wall. A thorough history and physical examination may help determine whether the tumor has invaded the prostate or the lymph nodes.
Gender Influence: Women and bladder cancerA greater percentage of females are diagnosed with bladder cancer at more advanced stages than men, which may contribute to the higher mortality rate in women. (Females are about twice as likely to die from the disease as males.) Contributing factors include a higher portion of nontransitional cell cancer histologies (rare cell types) that occur in women (adenocarcinoma, small cell carcinoma, squamous cell carcinoma); the relative thinness of an elderly woman’s bladder (perhaps permitting more rapid extravesical spread); and the older median age at presentation in women. Even higher incidences of bladder cancer were found in women who smoked, used hair dye, or drank tap water containing nitrates.
The following tests can provide essential information about the tumor:
Urinalysis can detect blood in the urine and malignant cytology.
Excretory urography can identify a large, early-stage tumor or an infiltrating tumor, delineate functional problems in the upper urinary tract, assess hydronephrosis, and detect rigid deformity of the bladder wall.
Retrograde cystography evaluates bladder structure and integrity. Test results help to confirm the diagnosis.
Pelvic arteriography can reveal tumor invasion into the bladder wall.
