[Urinary bladder carcinoma in biopsies of the last 50 years. Changes in frequency and sex distribution (author's transl)].

Comparative investigations of 440 urinary bladder biopsies from 1927 to 1957 and 1634 bladder biopsies from 1972 to 1976 showed the following: Epithelial bladder tumors are today found much more frequently among old age groups than they used to be. Bladder carcinoma have also been noticed more frequently among women in recent years. The sex ratio of men to women has dropped from 3.4:1 to 2.6:1. In the past five years there has been a steady rise in the frequency of carcinoma; the number of biopsies has risen 67% over the established rates of 1972. The percentage of pure squamous cell carcinoma of bladder cancer found from 1927 to 1957 was 5.1%, almost double the rate of 1972 to 1976, which was 2.8%; 89.5% of all tumors from the first time interval and 93% from the second were transitional cell carcinomas. Highly differentiated epithelial bladder tumors are today more frequently diagnosed than before. The ratio of high- to low-differentiated bladder tumors is presently 1.7:1 in patients under the age of 50, and 1.3:1 in patients over 50.