Survival Benefit of Combined Chemoimmunotherapy and Radiation Therapy in Patients with Recurrent or Metastatic Esophageal Cancer

Abstract

Purpose

Chemotherapy combined with immune checkpoint inhibitors (ICIs) has become the standard first-line treatment for recurrent or metastatic esophageal cancer, but its efficacy remains suboptimal. This study aimed to evaluate whether the addition of radiation therapy (RT) to ICIs can improve patients’ survival.

Methods and Materials

This retrospective cohort study analyzed clinical data from 178 patients with recurrent or metastatic esophageal cancer who were treated at the First Affiliated Hospital of USTC between December 2019 and October 2023. Based on their actual treatment regimens, patients were stratified into 2 groups: the chemoimmunotherapy-alone group (ICIs group) and the chemoimmunotherapy combined with RT group (ICIs + RT group). To minimize selection bias, propensity score matching was used to balance baseline characteristics between the groups before comparative analysis. The primary endpoint was overall survival, and the secondary endpoints were progression-free survival and safety.

Results

After propensity score matching, 128 patients were selected for the final analysis, with 64 patients in the ICIs + RT group and 64 patients in the ICIs group. The median follow-up time was 11.26 months (95% CI, 7.02-15.32). The median overall survival was 23.71 months in the ICIs + RT group and 13.00 months in the ICIs group (hazard ratio, 0.53; 95% CI, 0.31-0.88; P = .013). The median progression-free survival was 10.43 months in the ICIs + RT group and 7.27 months in the ICIs group (hazard ratio, 0.61; 95% CI, 0.39-0.94; P = .024). Combination of chemoimmunotherapy and RT was safe and tolerable. No treatment-related deaths occurred in either group.

Conclusions

Adding RT can significantly improve survival in patients with recurrent or metastatic esophageal cancer who are treated with chemoimmunotherapy, but further prospective trials are needed for validation.