EPIDEMIOLOGY AND ETIOLOGY OF BLADDER-CANCER

The incidence of bladder cancer continues to increase, with an estimat ed 53,000 new cases diagnosed in the United States in 1996-90% of whic h are transitional cell carcinomas. The male-to-female ratio is 3:1.A number of etiological factors are associated with the development of b ladder cancer, but in industrialized countries, cigarette smoking is t he most important. Specific chemicals have also been identified as cau sing bladder cancer, as have a number of occupational exposures to les s well-defined specific agents. Treatment with cytostatic drugs, espec ially cyclophosphamide, is associated with increased risk of bladder c ancer, as is treatment with radiotherapy for uterine cancer. In develo ping countries, especially in the Middle East and parts of Africa, inf ections with members of the genus Schistosoma are responsible for a hi gh incidence of bladder cancer-75% of which ale squamous cell carcinom as. Arsenic has been indicated as a bladder carcinogen in Argentina, C hile, and Taiwan. The reason for the high incidence of urinary tract c ancer in individuals suffering from Balkan nephropathy has yet to be d etermined. A careful history of patients with bladder cancer is an imp ortant and useful process in helping to identify causal factor and, in more than one-half the cases, a known relationship is found. Bladder cancer is a potentially preventable disease, with a significant morbid ity and mortality in many parts of the world. (C) 1997 Wiley-Liss, Inc .