The Effect of Timing of Adjuvant Therapy on Survival After Esophagectomy

Adjuvant chemotherapy (AC) after esophagectomy improves survival in esophageal cancer when induction therapy is not given; however, the optimal timing for initiation of AC is poorly characterized. We aimed to determine the impact of timing of AC on survival after esophagectomy.

The National Cancer Database was queried for patients with pT1-4aNxM0 esophageal cancer receiving AC with or without radiation from 2004 to 2015. The median and interquartile range of time to AC were determined. Patients were stratified by initiation of AC into 4 cohorts based on quartiles. Kaplan-Meier curves were generated and factors associated with survival were identified by Cox proportional hazards modeling. A separate analysis was performed with time to AC as a continuous variable.

A total of 1634 patients received AC after esophagectomy. Median time to receipt of AC was 59 (interquartile range, 45-78) days. There was no significant difference in overall survival at 5 years (P = .86) between groups. Median survival was 29 months in those receiving AC within 45 days and was 28 months in those receiving AC at other time points. On multivariable analysis, delay in receipt of AC beyond 45 days was not associated with inferior survival. This was preserved when time to AC was analyzed as a continuous variable (hazard ratio, 1.0; 95% confidence interval, 1.0-1.0).

Timing of initiation of AC after esophagectomy does not appear to impact survival. Given the highly variable postoperative course after esophagectomy, the decision to start AC should involve multidisciplinary discussion and be made on a patient-by-patient basis.