The role of adjuvant chemotherapy in locally advanced bladder cancer

Purpose: The standard of care for locally advanced bladder cancer (LABC) is neoadjuvant chemotherapy followed by cystectomy. However, the role of adjuvant therapy is unclear. The purpose of this study was to evaluate the outcomes of adjuvant chemotherapy for patients with LABC following neoadjuvant chemotherapy and cystectomy, and to determine whether select patients may benefit from adjuvant chemotherapy.Methods: The National Cancer Data Base (NCDB) was queried (2004-2013) for patients with newly diagnosed pT3-4N0-3M0 bladder cancer that received neoadjuvant chemotherapy and cystectomy. Patients were divided into two groups based on the adjuvant therapy they received: chemotherapy alone or observation. Statistics included multivariable logistic regression to determine factors predictive of receiving adjuvant chemotherapy, Kaplan-Meier analysis to evaluate overall survival (OS) and Cox proportional hazards modeling to determine variables associated with OS.Results: Altogether, 2592 patients met inclusion criteria; 901 (34.8%) patients received adjuvant chemotherapy, while 1691 (65.2%) were observed. Patients treated with adjuvant chemotherapy were more likely to have positive margins were younger and more likely to receive treatment at a nonacademic facility. There was no difference in median OS between patients treated with or without adjuvant chemotherapy (22.6 vs. 21.1 months; p=.267). However, a longer median OS was observed with the use of adjuvant chemotherapy was observed among patients with N2-3 disease (17.5 vs. 14.4 months; p=.005) and positive surgical margins (16.7 vs. 12.2 months; p=.025). On multivariate analysis, advancing age, pT4 stage, positive N stage, positive margins and lower socioeconomic status were associated with worse OS.Conclusions: In the largest study to date evaluating efficacy of adjuvant chemotherapy, while no difference in OS was observed for adjuvant chemotherapy in all patients, a longer OS was observed among patients with N2-3 disease or with positive surgical margins. Prospective studies are recommended to further evaluate these findings.