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Stages 0 and I bladder cancer are considered superficial, meaning cancer is found only in the lining of the bladder (urothelium) or in the connective tissue below the lining (lamina propria) but has not spread to the bladder muscle.

Stages II, III, and IV bladder cancer are considered invasive, meaning cancer has spread to the bladder muscle, the fatty tissue outside the muscle, and to the pelvic or abdominal wall (peritoneum). Stage IV bladder cancer can include cancer that has spread (metastasized) from the bladder to other places in the body such as the lungs, liver, or bones.