Does delay of adjuvant chemotherapy impact survival in patients with resected stage II and III colon adenocarcinoma?

Abstract

It is unclear whether delays in commencing adjuvant chemotherapy after surgical resection of colon adenocarcinoma adversely impact survival. Patients with stage II-III colon adenocarcinoma who received adjuvant chemotherapy at 2 centers were identified through the institutional tumor registry. Time to adjuvant chemotherapy, overall survival (OS), and relapse-free survival (RFS) were calculated from the day of surgery. Patients were dichotomized into early (time to adjuvant chemotherapy ≤ 60 days) and late treatment (time to adjuvant chemotherapy >60 days) groups. OS and RFS were compared using log-rank test and multivariate analysis by the Cox proportional hazards model. Of 186 patients included in the study, 49 (26%) had received adjuvant chemotherapy >60 days after surgical resection. Thirty percent of the delays were system related (eg, late referrals, insurance authorizations). Time to adjuvant chemotherapy >60 days was associated with significantly worse OS in both univariate analysis and a Cox proportional hazards model (hazard ratio, 2.17; 95% confidence interval, 1.08-4.36). Although difference in RFS between the 2 groups favored time to adjuvant chemotherapy <60, this did not reach statistical significance. Adjuvant chemotherapy delay >60 days after surgical resection of colon cancer is associated with worse OS.