Abstract
BACKGROUND: Neoadjuvant chemotherapy with concurrent radiotherapy (nCRT) is an accepted treatment regimen for patients with potentially curable esophageal and gastroesophageal junction (GEJ) adenocarcinoma. The purpose of this study is to evaluate whether induction chemotherapy (IC) before nCRT is associated with improved pathologic complete response (pCR) and overall survival (OS) when compared with patients who received nCRT alone for esophageal and GEJ adenocarcinoma. METHODS: Using the National Cancer Database (NCDB), patients who received nCRT and curative-intent esophagectomy for esophageal or GEJ adenocarcinoma from 2006 to 2015 were included. Chemotherapy and radiation therapy start dates were used to define cohorts who received IC before nCRT (IC + nCRT) versus those who only received concurrent nCRT before surgery. Propensity weighting was conducted to balance patient, disease, and facility covariates between groups. RESULTS: 12,460 patients met inclusion criteria, of whom 11,880 (95%) received nCRT and 580 (5%) received IC + nCRT. Following propensity weighting, OS was significantly improved among patients who received IC + nCRT versus nCRT (HR 0.82; 95% CI 0.74-0.92; p < 0.001) with median OS for the IC + nCRT cohort of 3.38 years versus 2.45 years for nCRT. For patients diagnosed from 2013 to 2015, IC + nCRT was also associated with higher odds of pCR compared with nCRT (OR 1.59; 95% CI 1.14-2.21; p = 0.007). CONCLUSION: IC + nCRT was associated with a significant OS benefit as well as higher pCR rate in the more modern patient cohort. These results merit consideration of a sufficiently powered prospective multiinstitutional trial to further evaluate these observed differences.