Gender differences in stage-adjusted bladder cancer survival.
OBJECTIVE
Gender differences have been observed in the prognosis of patients with bladder cancer. It has also been suggested that these differences are caused by a worse stage distribution at diagnosis among women. The purpose of this study was to evaluate whether women with bladder cancer have a worse prognosis even after adjustment for disease stage at first presentation.


METHODS
Data on patients with bladder cancer diagnosed between 1973 and 1996 and registered by one of the nine population-based Surveillance, Epidemiology, and End Results (SEER) cancer registries in the United States (n = 80,305) were obtained from the National Cancer Institute public domain SEER*Stat 2.0 package. Similar data on patients with bladder cancer diagnosed between 1987 and 1994 and registered by two population-based registries in the Netherlands (n = 1722) were obtained through the Comprehensive Cancer Centers, Amsterdam and South. Survival rates adjusted for mortality owing to other causes (ie, relative survival) were calculated for men and women within each category of the American Joint Committee on Cancer (SEER data) and TNM (Netherlands data) stage groupings.Results. In the United States, the 5-year relative survival rate of male patients with bladder cancer was calculated to be 79.5% (95% confidence interval 79.0% to 80.0%). Among women, the 5-year relative survival rate was significantly 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 was 96.5% versus 93.7%, 65.5% versus 59.6%, 58.8% versus 49.6%, and 27.1% versus 15.2%, respectively. The (sparser) data from the Netherlands were less conclusive. Women with Stage II and Stage IV disease fared worse than men but the reverse seemed to be true in Stage I disease.


CONCLUSIONS
Female patients with bladder cancer have a worse prognosis than male patients. It is unlikely that the difference can explained entirely by the more frequent diagnosis of higher stages at first presentation among women.
Mungan
N A
NA
Department of Urology, University Medical Center St. Radboud, Nijmegen, The Netherlands.
Aben
K K
KK
Schoenberg
M P
MP
Visser
O
O
Coebergh
J W
JW
Witjes
J A
JA
Kiemeney
L A
LA
D005260:Female; D006801:Humans; D008297:Male; D009426:Netherlands / Q000453:epidemiology; D011379:Prognosis; D012737:Sex Factors; D016019:Survival Analysis; D001749:Urinary Bladder Neoplasms / Q000401:mortality* / Q000473:pathology