Gender Specific Differences in Disease-Free, Cancer Specific and Overall Survival after Radical Cystectomy for Bladder Cancer: A Systematic Review and Meta-Analysis

Purpose: We summarize the evidence on gender specific differences in disease-free, cancer specific and overall survival after radical cystectomy for bladder cancer.

Materials and methods: We performed a systematic literature search of MEDLINE®, Embase® and the Cochrane Library in July 2017. Studies evaluating gender specific differences in disease-free, cancer specific or overall survival after radical cystectomy for bladder cancer were included in study. Analyses included random effect meta-analysis, subgroup analyses, meta-influence and cumulative meta-analyses. Funnel plots and the Egger test were used to assess publication bias.

Results: Of the 3,868 studies identified during the literature search 59 published between 1998 and 2017 were included in analysis. Of the studies 30 in a total of 38,321 patients evaluated disease-free survival, 44 in a total of 69,666 evaluated cancer specific survival and 26 in a total of 30,039 evaluated overall survival. Random effect meta-analyses revealed decreased disease-free, cancer specific survival and overall survival in female patients than in their male counterparts. Pooled estimates showed a HR of 1.16 (95% CI 1.06-1.27, p = 0.0018) for disease-free survival, 1.23 (95% CI 1.15-1.31, p <0.001) for cancer specific survival and 1.08 (95% CI 1.03-1.12, p = 0.0004) for overall survival. Subgroup analyses confirmed impaired disease-free, cancer specific and overall survival in female patients in all strata. Publication bias was evident only for studies of cancer specific survival (Egger test p = 0.0029). After adjusting for publication bias by the trim and fill method the corrected pooled estimated HR of cancer specific survival was 1.13 (95% CI 1.05-1.21, p = 0.0012).

Conclusions: Female patients who underwent radical cystectomy for bladder cancer demonstrated worse disease-free, cancer specific and overall survival than their male counterparts. The multifactorial etiology might include epidemiological differences, gender specific health care discrepancies and hormonal influences.