Definition of Bladder cancer:

Bladder cancer is a cancer that starts in the bladder. The bladder is the body part that holds and releases urine. It is in the center of the lower belly area.

Causes, incidence, and risk factors:

In the United States, bladder cancers usually start from the cells lining the bladder (called transitional cells).

These tumors are classified based on the way they grow:

• Papillary tumors have a wart-like appearance and are attached to a stalk.
• Nonpapillary (sessile) tumors are much less common. However, they are more invasive and have a worse outcome.

The exact cause of bladder cancer is uncertain. However, several things may make you more likely to develop it:

• Cigarette smoking. Smoking greatly increases the risk of developing bladder cancer. Up to half of all bladder cancers in men and several in women may be caused by cigarette smoke.
• Chemical exposure at work. About one in four cases of bladder cancer is caused by coming into contact with to cancer-causing chemicals at work. These chemicals are called carcinogens. Dye workers, rubber workers, aluminum workers, leather workers, truck drivers, and pesticide applicators are at the highest risk.
• Chemotherapy: The chemotherapy drug cyclophosphamide (Cytoxan) may increase the risk of bladder cancer.
• Radiation treatment: Women who had radiation therapy to treat cervical cancer have an increased risk of developing bladder cancer.
• Bladder infection: A long-term (chronic) bladder infection or irritation may lead to a certain type of bladder cancer.

Some research has suggested a link between artificial sweeteners and bladder cancer. The evidence is weak.