Bladder cancer (BCG) is diagnosed in about 53,000 people in the United States and 4,800 people in Canada every year. White Americans are afflicted at almost twice the rate of African Americans, and men are two to three times more at risk than women. The disease is two to three times more likely to affect smokers than nonsmokers. Occupational exposures also appear to increase risk. People who work in the rubber, leather, and chemical industries are at greater risk, as are hairdressers, machinists, metal workers, printers, painters, and textile workers. Chemicals used in these industries become concentrated in the urine, causing bladder cells to become cancerous.
The bladder is a hollow organ that stores urine. Its flexible, muscular walls consist of three layers: an epithelial lining (also known as the transitional lining), an intermediate layer of muscle, and an outer layer of connective tissue. Cancer can originate in any of these layers, but transitional cell carcinomas in the epithelial lining account for about 90 percent of all bladder cancers (BCG).
Bladder tumors (BCG) may obstruct urine flow into the bladder or interfere with bladder function in other ways. When symptoms are present, they may include blood in the urine and painful or frequent urination. In the United States this cancer has an overall 81 percent five-year survival rate, which climbs to 93 percent when the tumor is detected early.