Outcomes after chemoradiation alone for adenocarcinoma of the esophagus and gastroesophageal junction.

Abstract

138 Background: Definitive chemoradiation (CRT) is a standard treatment for esophageal cancer (EC), particularly squamous cell carcinoma (SCC). However, data for nonsurgical treatment of adenocarcinoma (AC) is limited, and response rates to CRT are lower in AC vs. SCC. Therefore, trimodality therapy is often preferred for AC. However, some patients with AC achieve clinical complete response (cCR) after CRT and decline surgery, or are medically inoperable. We therefore reviewed outcomes after CRT alone for esophageal AC. Methods: All patients receiving full-dose (≥ 50 Gy) CRT without surgery for Stage I-III AC of the esophagus or gastroesophageal junction (GEJ) from 2007-2012 at our institution were included. Complete clinical response (cCR) was defined as negative post-CRT biopsy, or SUVmax ≤ 3 on post-CRT PET if no biopsy was obtained. Local recurrence-free survival (LRFS), distant metastasis-free survival (DMFS) and overall survival (OS) were estimated using the Kaplan-Meier method. Results: 105 patients were included. 11 patients (10%) had T1-2N0 disease; the rest had T3+ or N+ disease. Median follow-up was 49 months. 85 patients (81%) received induction chemotherapy prior to CRT. Median OS was 25 months, with 3/5 year OS of 35% and 20% respectively. 67 patients (64%) had cCR, with median OS of 33 months and 3/5 year OS of 48% and 30%, compared to 15 months in incomplete responders (p<0.001). There were no long-term survivors among incomplete responders. 31 (46%) of cCR patients developed local failure, with 3 and 5 year LRFS of 53% and 46%. Median DMFS was 33 months in cCR patients. Of 10 patients who developed isolated local failure, 6 had salvage surgery, 3 had brachytherapy and 1 had laser ablation. Of these, 3 are alive and 2 are free of disease. Conclusions: This is the largest reported series of CRT alone for esophageal AC. In cCR patients, CRT alone is associated with long-term survival comparable to that expected with trimodality therapy. However, local recurrence still occurs in nearly half of patients with cCR. More study is needed to define which patients with cCR will benefit from immediate surgery after CRT, and improvements in therapy are needed to reduce local failure in patients not eligible for surgery.