As with most types of cancer, when cells in the body grow uncontrollably, they can form a tumor; when this happens with cells in the bladder, a person is said to have bladder cancer. This type of cancer is quite rare, with only approximately 5% of new cancer diagnoses in the nation being of this type. While the exact cause of bladder cancer is unknown, there are several factors that can increase a person's risk for diagnosis, including a family history of cancer in the bladder or urinary tract. Similarly, the cancer is more common in white men who are 55 years of age or older, so the risk is notably higher for this demographic. Routine bladder infections can increase a person's risk of developing bladder cancer, as can exposure to chemicals associated with smoking or working in certain industries. Medical history can also increase one's risk: individuals who have been treated with chemotherapy or who have taken drugs containing pioglitazone also see an increased risk.
The earliest and most common symptom of bladder cancer is urine in the blood; this does not have to be a significant amount of blood, nor does it have to happen regularly. Other symptoms can include more frequent urination, pain when urinating, or difficulty urinating. Once the cancer has started to spread, symptoms can evolve into pain in the lower back, swollen feet, unexplained weight loss, or feelings of weakness. Urine tests can show blood or cancerous cells in the urine; urine tumor marker tests can identify those substances released by cancerous bladder cells. A cystoscopy can be performed to get a visual image of the bladder and any potential tumor growth; a resection of the tumor can be done to determine if it is cancerous or not. Other imaging tests can identify tumor growth in other aspects of the urinary tract. Treatment can range from removal of the tumor to removal of part or all of the bladder, depending on the severity of the condition. Immunotherapy or chemotherapy can be used to attack and destroy the cancer cells in the body. Prevention cannot always be completely effective due to genetic factors, but overall risk can decline through smoking cessation, drinking ample amounts of fluid, and eating more fruits and leafy, green vegetables.