What Is Bladder Cancer?

Bladder cancer occurs when there are abnormal, cancerous cells growing in the bladder. The American Cancer Society (ACS)* estimated 73,000 diagnosed cases of bladder cancer in 2013. Bladder cancer victims are four times more likely to be men than women, and twice as likely to be Caucasians. Most patients are over age 55 when diagnosed.

Types of bladder cancer

There are several types of bladder cancers, including:

Transitional cell (urothelial) carcinoma

Transitional cell carcinoma begins in the cells lining the inside of the bladder. Transitional cells also line the other parts of the urinary tract, including the kidneys, ureters and urethra. Transitional cell carcinoma is the most common kind of bladder cancer, occurring in about 95 percent of cases.

Squamous cell carcinoma

Squamous cell carcinoma begins in squamous cells—thin, flat cells found in the tissue that resemble the surface of the skin, the lining of the hollow organs of the body, and the passages of the respiratory and digestive tracts. About one to two percent of bladder cancers are squamous cell carcinomas.


Adenocarcinoma begins in the cells of glandular structures lining certain organs in the body. Adenocarcinomas account for only about one percent of bladder cancers.

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