The Impact of Adjuvant Therapy on Survival After Esophagectomy for Node-negative Esophageal Adenocarcinoma

Abstract

Objective: Determine whether adjuvant chemotherapy is associated with a survival benefit in high risk T2-4a, pathologically node-negative distal esophageal adenocarcinoma.

Summary of background data: There is minimal literature to substantiate the NCCN guidelines recommending adjuvant therapy for patients with distal esophageal adenocarcinoma and no pathologic evidence of nodal disease.

Methods: The National Cancer Database was used to identify adult patients with pT2-4aN0M0 esophageal adenocarcinoma who underwent definitive surgery (2004-2015) and had characteristics considered high risk by the NCCN. Patients were stratified by receipt of adjuvant chemotherapy with or without radiation. The primary outcome was overall survival, which was evaluated using Kaplan-Meier and multivariable Cox Proportional Hazards models. A 1:1 propensity score-matched analysis was also performed to compare survival between the groups.

Results: Four hundred three patients met study criteria: 313 (78%) without adjuvant therapy and 90 who received adjuvant chemotherapy with or without radiation (22%). In both unadjusted and multivariable analysis, adjuvant chemotherapy with or without radiation was not associated with a significant survival benefit compared to no adjuvant therapy. In a subgroup analysis of 335 patients without high risk features by NCCN criteria, adjuvant chemotherapy was not independently associated with a survival benefit.

Conclusion: In this analysis, adjuvant chemotherapy with or without radiation was not associated with a significant survival benefit in completely resected, pathologically node-negative distal esophageal adenocarcinoma, independent of presence of high risk characteristics. The risks and benefits of adjuvant therapy should be weighed before offering it to patients with completely resected pT2-4aN0M0 esophageal adenocarcinoma.

Figure 1.

STROBE diagram of (a) high risk and (b) low risk patients analyzed

Figure 2.

Kaplan-Meier survival curves for (a) unmatched and (b) propensity score-matched high risk patients with pT2–4N0M0 distal esophageal adenocarcinoma, stratified by type of adjuvant therapy. The p value refers to the log-rank test. Shaded regions represent the 95% confidence interval. Numbers at risk are provided beneath the graph