Incidence of primary urethral carcinoma in the United States

Primary urethral carcinoma is rare, and the demographic correlates of its incidence have not been examined using population-based data.

The National Cancer Institute Surveillance, Epidemiology, and End Results database was used to identify persons diagnosed with primary urethral carcinoma from 1973 to 2002. During this period, the Surveillance, Epidemiology, and End Results program included population-based tumor registries in nine geographic areas that represented approximately 10% of the U.S. population. The incidence rates were tabulated for the major histologic subtypes according to age, sex, and race.

Primary urethral carcinoma was identified in 1075 men and 540 women, with an annual age-adjusted incidence rate of 4.3 per million and 1.5 per million, respectively. The annual incidence rate increased with age to a peak of 32 per million men and 9.5 per million women in the 75 to 84-year age group. The rate was 5.0 per million and 2.5 per million for African Americans and whites, respectively. The histologic types were transitional cell carcinoma in 888 patients (55%), squamous cell carcinoma in 348 (21.5%), and adenocarcinoma in 265 (16.4%). The incidence of the three primary histologic types varied by race and sex.

In the United States, the incidence of urethral carcinoma is relatively higher in men and African Americans, with a histologic profile differing from that previously described.