AUTHOR=Zheng Si-Yue , Qi Wei-Xiang , Zhao Sheng-Guang , Chen Jia-Yi 

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

JOURNAL=Frontiers in Oncology

VOLUME=Volume 12 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/oncology/articles/10.3389/fonc.2022.897476

DOI=10.3389/fonc.2022.897476

ISSN=2234-943X

ABSTRACT=Background: To assess the clinical benefit of postoperative radiotherapy (PORT) in patients with esophageal cancer who treated with neoadjuvant chemotherapy (NAC) and surgery via a national population-based database. 
Methods: Patients diagnosed with esophageal cancer between 2004 and 2015 were identified from the Surveillance, Epidemiology, and End Results (SEER) database. Kaplan-Meier survival analysis was used to compare 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 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, 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 no-RT group over 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, while 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 EC patients. Well-designed prospective trials are needed to confirm our findings.