Tumors of various sorts, principally vascular or villous in character, occasionally form in the bladder, in consequence of long-continued catarrh of its mucous membrane; warty excresences are also formed in profusion over the surface of the bladder. Cancer occasionally affects this organ as well as nearly every other in the body.

The treatment of these affections also pertains to the domain of surgery, and need not be considered further here, especially as they are very rare; and no treatment can be applied to them on account of the difficulty in reaching the scat of the disease.