Etiology of bladder cancer.

That the etiology of bladder cancer involves environmental factors is well documented. Most chemical carcinogens probably affect the urothelial cells via their presence in the urine. As an important cofactor, cell-proliferative activity may be increased by urinary bladder infection, irritation by bladder stones or through the action of a variety of direct acting chemicals or agents. Among the known causative factors, avoidable major ones are occupational exposure to certain chemicals such as benzidine and 4-aminobiphenyl, cigarette smoking, and bilharzial infection, which could be eradicated by a combination of praziquantel, antihelminth therapy, education, and improvements in social welfare. An anticarcinogenic drug, cyclophosphamide, used as an immunosuppressive agent also seems to be associated with a high risk of idiopathic induction of bladder cancer and physicians should therefore pay particular attention to its diverse effects when considering its prescription. In contrast to the above, the consumption of coffee and tea containing artificial sweeteners is now thought unlikely to be a major risk. So far there is no good biochemical tool to predict individual exposure to bladder carcinogens/or relative risk of bladder-cancer development. However, acetylation capacity can be applied to assess susceptibility to carcinogenic amines in people exposed in their working environment. Progress in molecular-biological analysis will hopefully bring to light etiology-specific DNA damage in bladder tumors, and it may prove useful for prediction of tumor behavior in the near future.