Characteristics of female non-muscle-invasive bladder cancer in Taiwan: Association with upper tract urothelial carcinoma and end-stage renal disease

OBJECTIVES Urothelial carcinogenic mechanisms may differ between men and women. We investigated gender differences in the pathological characteristics and clinical outcomes of non-muscle-invasive bladder urothelial carcinoma (UC). METHODS We retrospectively reviewed a total of 413 consecutive patients, 285 men (69.0%) and 128 women (31.0%), with primary non-muscle-invasive bladder UC, treated with transurethral resection between January 1997 and July 2005. A single pathologist reviewed all pathology data. All statistical comparisons were two-sided. RESULTS Only a small proportion (2.3%) of female patients were current smokers compared with a larger proportion of males (48.1%). Female patients had more end-stage renal disease (ESRD) (20.3%) at diagnosis and/or previous or synchronous upper tract UC (34.4%) than males (5.6% and 14.7% for two disease conditions, respectively). There were no gender differences in pathological phenotypes such as tumor multiplicity, tumor grade, or stage. In a Cox proportional hazard model, female patients had more metachronous upper tract UC than males but had similar chances of recurrence and progression as males. Combining both genders, tumor multiplicity, stage, and continued smoking were independent prognostic factors predicting bladder recurrence. CONCLUSIONS There were no gender differences in clinicopathological characteristics such as tumor multiplicity, grade, stage, or risk of recurrence or progression. Smoking is not a major risk factor for women in Taiwan. Female patients with bladder cancer tended to have more upper tract UC and ESRD than males.