Timing of adjuvant chemotherapy and overall survival following radical cystectomy

Abstract

Background: We investigated the relationship between timing of adjuvant chemotherapy on overall survival following radical cystectomy.

Methods: We retrospectively reviewed the National Cancer Data Base for patients with newly diagnosed pT2-T4, N0, M0 urothelial cell carcinoma who received no treatment prior to radical cystectomy. Patients who received no adjuvant chemotherapy or who received adjuvant chemotherapy more than 45 days after radical cystectomy were propensity matched to patients receiving adjuvant chemotherapy within 45 days of radical cystectomy. Selection bias was assessed by comparing the length of stay, readmission rate, and surgical approach between groups. Median survival was calculated using Kaplan-Meier analysis. Adjusted hazard ratios and 95% confidence intervals were calculated from a multivariable Cox regression model to examine factors affecting overall survival.

Results: From 2004 to 2014, 284 patients with muscle-invasive bladder cancer met inclusion criteria. Patients receiving chemotherapy within 45 days had the best 5-year overall survival (47.0%, 95%CI: 40.6%-53.2%) compared to those receiving chemotherapy after 45 days (37.5%, 95%CI: 31.4%-43.7%). Chemotherapy after 45 days and no adjuvant chemotherapy were significant predictors of worse overall survival compared to chemotherapy within 45 days (1.27, 1.02-1.59, P = 0.033 and 1.41, 1.12-1.78, P = 0.003). Receiving no adjuvant chemotherapy was not significantly different than chemotherapy after 45 days (1.11, 0.89-1.38, P = 0.348). Significant predictors of poorer overall survival were female sex (1.37, 1.04-1.81, P = 0.028), Medicare (1.37, 1.06-1.76, P = 0.016), pT3 stage (1.79, 1.35-2.38, P < 0.001), and pT4 stage (3.00, 2.20-4.01, P < 0.001). Significantly more patients with length of stay ≤7 days following RC received chemotherapy within 45 days (53.2%) compared to those who received adjuvant chemotherapy after 45 days after RC (44.0%) or no adjuvant chemotherapy (43.0%; P = 0.0369).

Conclusions: Initiation of adjuvant chemotherapy within 45 days of radical cystectomy for patients with pT2-4 bladder cancer was associated with an overall survival benefit compared to patients who received adjuvant chemotherapy after 45 days or no adjuvant chemotherapy.

Keywords: Adjuvant chemotherapy; Muscle-invasive bladder cancer; NCDB; Radical cystectomy; Timing of adjuvant chemotherapy.