Comparison of definitive chemoradiotherapy and surgery in patients with clinical T1bN0M0 esophageal cancer: A multicenter retrospective study: the Korean Radiation Oncology Group 21-10 trial

Abstract

Purpose: To compare the treatment outcomes between esophagectomy and definitive chemoradiotherapy (DCRT) in patients with cT1bN0M0 esophageal squamous cell carcinoma (ESCC) Methods: Medical records of patients with cT1bN0M0 ESCC who were treated at 11 institutions in Korea between January 2010 and April 2020 were retrospectively reviewed. Disease recurrences and overall survival (OS) were compared between patients who had undergone esophagectomy and DCRT. Results: A total of 333 and 88 patients who had undergone esophagectomy and DCRT, respectively, were included. Patients in the surgery group were significantly younger and had better performance status compared to those in the DCRT group. Clinical complete response (cCR) was achieved in 84 DCRT patients (95.5%) following the treatment. With a median follow-up of 55 months (range, 0.4-134), instances of disease recurrences were observed in 19.2% (64 patients) and 17.0% (15 patients) in the surgery and DCRT groups, respectively. The 5-year locoregional disease-free survival (LRDFS) rate was 86.0% and 75.4% in the surgery and DCRT groups, respectively (p = 0.336). The 5-year distant disease-free survival rate (DDFS) was 84.5% and 92.9% for the surgery and DCRT groups, respectively (p = 0.073). The surgery group displayed a trend toward improved OS (77.8% vs. 65.8%, p = 0.072) on univariate analysis, whereas no significant difference was observed in disease-free survival (DFS) between the two groups (78.5% vs. 74.7%, p = 0.854). Conclusions: Our study demonstrated that DCRT was equivalent to esophagectomy in terms of LRDFS, DDFS, DFS, and OS rates in patients with cT1bN0M0 ESCC. Key words: Esophageal cancer, definitive chemoradiotherapy, ER, radical esophagectomy