Data Sheet 1_Impact of adjuvant immunotherapy on prognosis in esophageal squamous cell carcinoma patients following neoadjuvant immunochemotherapy.docx

IntroductionThe CheckMate-577 trial confirmed that adjuvant nivolumab significantly prolonged disease-free survival (DFS) in patients with esophageal cancer who had residual disease after neoadjuvant chemoradiotherapy (nCRT). However, whether postoperative adjuvant immunotherapy (AIT) is necessary following neoadjuvant immunochemotherapy (nICT) remains highly controversial. This study aims to explore the efficacy of AIT in esophageal squamous cell carcinoma (ESCC) patients who underwent nICT.
MethodsA multicenter, retrospective study was conducted on 323 ESCC patients who underwent nICT followed by R0 resection. Patients were divided into AIT group and non-AT group, with further stratification based on pCR status. Stable inverse probability of treatment weighting (sIPTW) was used to balance baseline characteristics. Primary endpoint was overall survival (OS). Secondary endpoints were disease-free survival (DFS) and cancer-specific survival (CSS). Survival outcomes were analyzed using Kaplan-Meier curves.
ResultsIn overall patients, AIT significantly improved OS (2-year OS: 95.8% vs. 84.4%, P = 0.008) and CSS (2-year CSS: 96.8% vs. 89.9%, P = 0.036), while no significant survival benefit from AIT was observed for pCR patients. However, in non-pCR patients, AIT significantly improved OS (2-year OS: 93.5% vs. 78.8%, P = 0.024) and CSS (2-year CSS: 95.0% vs. 85.9%, P = 0.047). No significant differences were observed between adjuvant immunochemotherapy (AICT) and adjuvant immune checkpoint inhibitor monotherapy (AIMT).
ConclusionThe study showed that AIT could bring prognosis benefits for patients receiving nICT, especially in non-pCR patients.