Postoperative adjuvant chemotherapy versus chemoradiotherapy for node-positive esophageal squamous cell carcinoma: a propensity score-matched analysis

BACKGROUND AND PURPOSE: After esophagectomy, adjuvant chemotherapy (S + CT) and adjuvant chemoradiotherapy (S + CRT) can improve survival in patients with node-positive resectable esophageal cancer. However, we are not aware of any studies that directly compared these adjuvant treatments. This study aimed to compare S + CT and S + CRT for patients with esophageal cancer. MATERIALS AND METHODS: We retrospectively identified patients with node-positive esophageal squamous cell carcinoma who underwent S + CT or S + CRT at Sichuan Cancer Hospital during 2008–2017. The patients’ characteristics were compared, as well as their overall survival (OS) and disease-free survival (DFS) outcomes. Propensity score matching was used to create balanced patient groups according to adjuvant treatment, and a Cox proportional hazards model was used to identify factors that predicted the survival outcomes. RESULTS: The 859 eligible patients underwent S + CRT (250 patients, 29.1%) or S + CT (609 patients, 70.9%). After propensity score matching (247 patients per group), the 5-year OS rates were 41.8% for S + CRT and 26.8% for S + CT (p = 0.028), and the 5-year DFS rates were 37.2% for S + CRT and 25.5% for S + CT (p = 0.012). Multivariate Cox regression analysis of the matched samples revealed that, relative to the S + CT group, the S + CRT group had better OS (hazard ratio: 0.71, 95% CI: 0.56–0.91; p = 0.006) and DFS (hazard ratio: 0.70, 95% CI: 0.56–0.88; p = 0.002). CONCLUSION: Among patients with node-positive resectable esophageal squamous cell carcinoma, S + CRT was associated with better OS than S + CT. A multicenter randomized clinical trial is warranted to confirm these findings.