Carcinogenesis in the Human Urinary Bladder

Abstract

EXPOSURE of industrial workers to potent urinary-bladder carcinogens is a quasi-experimental situation that offers a unique opportunity to study the natural history of human cancer. Crabbe and his co-workers^{1 , 2} adopted periodic cytologic examinations of the urinary sediment as the principal means of follow-up study of these unfortunate people. They demonstrated the reliability and practical value of this technic in the diagnosis of early bladder cancer.Since 1957 we have been studying the cellular makeup of the urinary sediment of a large group of workers exposed to para-aminodiphenyl (xenylamine). This substance was identified as a urinary-bladder carcinogen in dogs by Walpole, . . .