Pathologic Complete Response Is an Independent Predictor of Improved Survival Following Neoadjuvant Chemoradiation for Esophageal Adenocarcinoma

Abstract

IntroductionReports of improved survival in patients with pathologic complete response (pCR) to neoadjuvant therapy for esophageal and gastroesophageal junction (GEJ) adenocarcinoma is extrapolated from heterogeneous studies that include squamous cell histology. We sought to determine if pCR is associated with a survival advantage in a homogenous group of patients with esophageal adenocarcinoma. MethodsThis is a single institution analysis of all patients with T2–T4 or node positive esophageal adenocarcinoma treated with neoadjuvant chemoradiotherapy and esophagectomy between 2004 and 2014. Patients were divided into two groups based on pathological response, pCR vs. incomplete pathological response (iPR). Survival outcomes were evaluated using standard Kaplan-Meier methods and multivariable Cox regression models. ResultsA total of 205 patients were included in the study: 38 (19 %) patients with pCR and 167 patients (81 %) with iPR. The two groups were similar with respect to clinical stage, age, gender, comorbid conditions, ECOG status, smoking, and alcohol use. Patients in the pCR group had a higher percentage of tumors located in middle third of esophagus (11 vs. 2 %, p = 0.04) while tumor grade was similar in both groups. Median follow-up was 50 months, range 2–109 months. The 3-year overall (OS) and recurrence-free survival (RFS) for iPR was 48 and 39 %, respectively, vs. 86 and 80 % for pCR group, respectively. ConclusionThis analysis of a cohort of homogeneous patients with esophageal adenocarcinoma undergoing multimodality therapy showed that pCR is an independent predictor of improved RFS and OS. This data contributes to a growing body of evidence highlighting the benefits of neoadjuvant therapy specific to esophageal adenocarcinoma particularly when pCR is achieved.