Concurrent Chemoradiotherapy With S-1 Superior to RT Alone in Esophageal Cancer

Findings from a phase 3, randomized clinical trial showed concurrent chemoradiotherapy (CCRT) with S-1 demonstrated significant benefit over radiotherapy (RT) alone in older patients with esophageal cancer (JAMA Oncol. 2021 Aug 5:e212705.).

Since many older patients with esophageal cancer are unable to complete the standard CCRT, Yongling Ji, MD, Department of Radiation Oncology, Chinese Academy of Science, Hangzhou, China, and colleagues conducted this study in hopes of finding an alternative treatment for older patients with esophageal cancer who are unable to complete the standard CCRT.

The open-label clinical trial was conducted across 23 Chinese centers from June 2016 and August 2018. Eligible patients included those with histologically confirmed esophageal cancer, stage IB to IVB disease (based on the 6th edition of the American Joint Committee on Cancer), and an Eastern Cooperative Oncology Group performance status of 0 to 1. A total of 298 patients, aged 70 to 85 years, were enrolled. Patients were randomly assigned (1:1) to receive CCRT with S-1 or RT alone.

The primary end point was the 2-year overall survival rate using intention-to-treat analysis. 

The complete response rate for patients in the CCRT group was 41.6%, compared to 26.8% in the RT group (P = .007). Furthermore, at the median follow-up of 33.9 months, the CCRT group had a significantly higher 2-year overall survival (OS) rate than the RT group (53.2% v.s 35.8%; hazard ratio, 0.63; 95% CI, 0.47-0.85; P = .002). 

The incidence of grade 3 or higher toxic effects between the CCRT and RT groups were similar, with the only significant difference being that grade 3 or higher leukopenia occurred in more patients in the CCRT group (9.5% v.s 2.7%; P = .01). Treatment-related deaths occurred in three patients (2.0%) in the CCRT group and four (2.7%) in the RT group.

“In this phase 3 randomized clinical trial, CCRT with S-1 was tolerable and provided significant benefits over RT alone in older patients with esophageal cancer,” concluded Dr Ji et al. —Alexandra Graziano