It is a cancer caused by mutation in the cells of epithelial lining of the bladder mainly. It is known as transitional cell carcinoma or urothelial cell carcinoma. Urinary bladder is an organ which stores urine temporarily and then the urine passes through the urethra. It has transitional epithelium in its wall which helps in changing the size and shape of the urinary bladder, so that urine can be stored properly.When there is 500 ml of urine in the urinary bladder then there are signals from it to the brain which finally helps send signals to  urinate. In cancer there is abnormality in the cell cycle and the cell starts growing abnormally and causes growth of an abnormal mass of tissue which can spread to other organs through lymphoid tissue or blood (hematogenous spread).
The incidence of bladder cancer is higher for men than women as there are androgen receptors in men and this plays a very important role in the development of cancer.

This arises from occupational exposure of certain carcinogens like benzidine in workers who work in the printing and metal industries. Benzidine is also used in the production of the dyes. It also affects people who work in the rubber and textile industry. Auto mechanics are severely exposed to the hydrocarbons and petroleum based chemicals causing this type of cancer. Smoking also increases carcinogens which can cause the bladder cancer. Certain carcinogens are in direct contact of the bladder which can be excreted in urine by drinking of water.

Drinking plenty of the fluids can flush off the carcinogens in the bladder before they cause any damage. Smoking has a direct effect on the risk of developing the cancer. So, quit smoking.