Gender differences in stage-adjusted bladder cancer survival

Objectives. Gender differences have been observed in the prognosis of patie nts with bladder cancer, it has also been suggested that these differences are caused by a worse stage distribution at diagnosis among women. The purp ose of this study was to evaluate whether women with bladder cancer have a worse prognosis even after adjustment for disease stage at first presentati on. Methods. Data on patients with bladder cancer diagnosed between 1973 and 19 96 and registered by one of the nine population-based Surveillance, Epidemi ology, and End Results (SEER) cancer registries in the United States (n = 8 0,305) were obtained from the National Cancer Institute public domain SEER* Stat 2.0 package. Similar data on patients with bladder cancer diagnosed be tween 1987 and 1994 and registered by two population-based registries in th e Netherlands (n = 1722) were obtained through the Comprehensive Cancer Cen ters, Amsterdam and South. Survival rates adjusted for mortality owing to o ther causes (ie, relative survival) were calculated for men and women withi n each category of the American Joint Committee on Cancer (SEER data) and T NM (Netherlands data) stage groupings. Results. In the United States, the 5-year relative survival rate of male pa tients with bladder cancer was calculated to be 79.5% (95% confidence inter val 79.0% to 80.0%). Among women, the 5-year relative survival rate was sig nificantly worse: 73.1% (95% confidence interval 72.2% to 74.0%). The male versus female 5-year survival rate among stage groups I, II, III, and IV wa s 96.5% versus 93.7%, 65.5% versus 59.6%, 58.8% versus 49.6%, and 27.1% ver sus 15.2%, respectively. The (sparser) data from the Netherlands were less conclusive. Women with Stage II and Stage IV disease fared worse than men b ut the reverse seemed to be true in Stage I disease. Conclusions. Female patients with bladder cancer have a worse prognosis tha n male patients. It is unlikely that the difference can explained entirely by the more frequent diagnosis of higher stages at first presentation among women. UROLOGY 55: 876-880, 2000. (C) 2000, Elsevier Science Inc.