Survival following Induction Chemotherapy and Esophagectomy is not Improved by Adjuvant Chemotherapy

Background It remains unclear whether postoperative chemotherapy improves survival among patients with esophageal squamous cell carcinoma who have undergone preoperative chemotherapy and radical resection. Methods Patients treated between January 2000 and December 2016 were reviewed. Eligible patients were divided into two groups: perioperative chemotherapy (pre- and postoperative chemotherapy [PC]) and neoadjuvant chemotherapy only (NC). The primary endpoint was disease-free survival (DFS); secondary endpoints were overall survival (OS) and toxicities attributable to postoperative chemotherapy. To minimize the effect of patient heterogeneity between the two groups, we used propensity-score matching. The survival analysis was performed using univariate analysis and a multivariable Cox regression model. Results In total, 252 patients were included in the study. Most were men (208/252 [82.5%]); median age was 59. The follow-up rate was 93.3% . Age, performance status, minimally invasive surgery and Clavien-Dindo classification were statistically different between the groups ( p p =0.372) and OS (68.6% vs. 62.4%, p =0.359) were not statistically different between the NC and PC group. Cox regression identified both pathological nodal stage and tumor regression grade are independent prognostic factors for DFS and OS ( p p =0.872) or OS (HR=1.297 [95% CI, 0.606-2.775], p =0.504). In the PC group,8.5% of patients (5/59) had grade ≥3 toxicity. Conclusions Adjuvant chemotherapy is not indicated for patients with locally advanced ESCC following neoadjuvant platinum-based chemotherapy and surgery.