Depending on its extension, bladder cancer is classified into 4 stages:
- Stage I: the cancer is present in the inner lining of the bladder; the muscular bladder wall is not affected.
- Stage II: the cancer has extended from the inner lining of the bladder to the bladder wall
- Stage III: at this stage, the cancer cells have spread from the bladder wall to surrounding tissue: prostate gland, vagina, or uterus.
- Stage IV: at stage 4 (the last stage), the cancer cells have proliferated to the lymph nodes, abdominal wall, lungs, bones and/or other organs.