No survival benefit could be obtained from adjuvant radiotherapy in esophageal cancer treated with neoadjuvant chemotherapy followed by surgery: A SEER-based analysis.

Background: The aim of this study is to assess the clinical benefit of postoperative radiotherapy (PORT) in patients with esophageal cancer (EC) who treated with neoadjuvant chemotherapy (NAC) and surgery via a national population-based database. Methods: Patients diagnosed with EC between 2004 and 2015 were identified from the Surveillance, Epidemiology, and End Results (SEER) database. Kaplan-Meier survival analysis was used to compare the overall survival (OS) and cause-specific survival (CSS) difference between PORT vs. no-radiotherapy (RT) groups before and after propensity score matching (PSM). After PSM for baseline characteristics, Cox proportional hazard regression was performed to investigate the factors associated with OS. Results: A total of 321 patients were included in the analysis. Of them, 91 patients (28%) received PORT. In the unmatched population, the no-RT group had improved OS compared with PORT (44 vs. 25 months, p = 0.002), and CSS was similar in patients undergoing NAC with or without PORT (42 vs. 71 months, p = 0.17). After PSM for baseline characteristics, the OS benefit of the no-RT group over the PORT group remained significant with a median OS of 46 vs. 27 months (p = 0.02), and CSS remained comparable between groups (83 vs. 81 months, p = 0.49). In subgroup analyses, PORT did not improve the OS among patients with adenocarcinoma in the subgroups of cN0, cN1, and cN2-3 (all p > 0.05). In Cox regression, aged ≥71 years old, cT3-4, cN2-3, and receiving PORT were independent predictors of worse OS, whereas cT4 and cN2-3 were independent predictors of worse CSS (all p < 0.05). Conclusions: The present study demonstrated that no survival benefit could be obtained from the additional use of PORT after NAC and surgery in patients with EC. Well-designed prospective trials are needed to confirm our findings.