7/30/2019 27351729 Bladder Cancer

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Bladder cancer is the second most common malignancy affecting

the genitourinary system. It is largely a preventable disease because

most cases probably result from exposure to environmental carcino-

gens, the most important of which is cigarette smoke. Most tumors aris-

ing in the bladder are transitional cell carcinomas; other pathologies are

far less common. Most tumors diagnosed in the United States are con-

fined to the epithelial or transitional cell layer of the bladder and are

easily treated by transurethral resection. These tumors generally are low

grade and have low potential for metastatic spread. Tumors that are con-

sidered to be high grade and/or invade the deeper layers of the bladder

wall have a much greater potential for metastatic spread. Such tumors

can be cured if no evident or occult metastasis exists. The treatment of

metastatic disease still is marginal, although recent improvements in

therapy have been achieved, leading to a small fraction of patients (