Effectiveness of platinum-based adjuvant chemotherapy for muscle-invasive bladder cancer: A weighted propensity score analysis.

392Background: The clinical evidence of adjuvant chemotherapy (AC ) is less robust than neoadjuvant chemotherapy (NAC). However, several surveys suggest that urologists prefer to use AC more frequently than NAC. We evaluate the clinical benefit of adjuvant platinum based chemotherapy following radical cystectomy (RC) for muscle-invasive bladder cancer (BCa) in routine clinical practice. Methods: This observational study was conducted to compare the effectiveness of AC versus observation postcystectomy in patients with clinicallymuscle-invasive BCa. Cancer-specific survival (CSS) and overall survival (OS) between the AC group and RC alone group were compared using Kaplan-Meiyer method and log-rank test. After adjusting for background factors using propensity score weighting, differences in CSS and OS between these two groups were compared. Subgroup analyses by the pathological characteristics were performed. Results: In total, 322 patients were included in this study. Of these, 23% received AC postcystecto...