The bladder is part of your urinary tract. The urinary tract rids your body of liquid waste. Bladder cancer means that certain cells in the urinary tract have changed in ways that aren’t normal.

When Bladder Cancer Forms

Cancer is a disease in which cells in an area of the body begin changing and multiplying out of control. The multiplying cells may form a lump of tissue (tumor). With time, the cancer cells destroy healthy tissue. They may spread to other parts of the body. Why cells become cancerous is not clear. But bladder cancer is strongly linked to cigarette smoking. The longer a person smokes and the more a person smokes, the greater that person’s chances of developing bladder cancer.

Types of Cancer That May Form

Three types of bladder cancer may form:

• Papillary tumors stick out from the bladder lining on a stalk. They tend to grow into the bladder cavity, away from the bladder wall, instead of deeper into the layers of the bladder wall.
• Sessile tumors lie flat against the bladder lining. Sessile tumors are much more likely than papillary tumors to grow deeper into the layers of the bladder wall.
• Carcinoma in situ (CIS) is a cancerous patch of bladder lining. The patch may look almost normal or may look inflamed.

Each type of tumor can be present in one or more areas of the bladder, and more than one type can be present at the same time.