Bladder cancer is the rapid, uncontrolled growth of abnormal cells in the lining of the bladder, the part of the urinary tract that serves as a collection pouch for urine. The most common symptom of bladder cancer is blood in the urine (hematuria), and other symptoms include pain during urination and frequent urination.

The cause of bladder cancer is not known. But it is more likely to develop in smokers than in nonsmokers. Men are more likely than women to develop bladder cancer.

Treatment depends on the stage of the cancer. Treatment may include surgery, chemotherapy, immunotherapy, or radiation therapy.