Background  The treatment of locally advanced esophageal cancer with chemoradiotherapy combined with programmed cell death protein-1 (PD-1) is in the preliminary research stage, therefore the efficacy and safety of the treatment mode need further clinical verification.

  Objective  To investigate the curative effect and survival benefit of chemoradiotherapy combined with PD-1 for locally advanced esophageal cancer.

  Methods  From July 2015 to April 2021, clinical data about 46 patients with pathology-confirmed locally advanced esophageal squamous cancer who were confirmed by pathology in our hospital were retrospectively analyzed. There were 24 patients received chemoradiotherapy combined with PD-1 (combined group) and 22 patients received chemoradiotherapy (chemoradiotherapy group). Platinum, fluorouracil and taxanes were used for combined chemotherapy, and the radiation therapy dose was 50-63Gy in 25-30 fractions, which was used for image guided radiation therapy (IGRT). Overall survival (OS) and progression-free survival (PFS) were calculated by Kaplan-Meier method.

  Results  There were 23 males and 1 female in the combined group with the mean age of 58.5 years (11 cases in stage Ⅲ and 13 cases in stage Ⅳ). There were 16 males and 6 females in chemoradiotherapy group with the mean age of 63.4 years (12 cases in stage Ⅲ and 10 cases in stage Ⅳ). No statistically significant difference was found between the two groups at baseline (P＞0.05). The short-term efficacy evaluation on the combined group included 2 cases of complete response (CR), 6 cases of partial response (PR), 10 cases of stable disease (SD) and 6 cases of progressive disease (PD). For the chemoradiotherapy group, there were 1 case of CR, 3 cases of PR, 11 cases of SD and 7 cases of PD. The difference between the two groups showed no statistical significance (P=0.706). The objective response rate (ORR)(33.3% vs 18.2%) and disease control rate (DCR) (75% vs 68.2%) in the combined group were higher than those in the chemoradiotherapy group, without statistically significant differences (P>0.05). The median survival and 1-year OS rate were 33 months and 89.2% in the combined group, and 20 months and 62.9% in the chemoradiotherapy group, with statistically significant difference between the two groups (P=0.042). The median progression-free survival and 1-year PFS rate were 22 months and 70% in the combined group, showing no statistically significant difference compared to 20 months and 53.7% in the chemoradiotherapy group (P=0.38). Most patients had grade 1-2 acute adverse reactions, and no serious adverse reactions occurred after chemoradiotherapy combined with PD-1.

  Conclusion  Chemoradiotherapy combined with PD-1 is a safe and efficacious treatment for patients with locally advanced esophageal cancer, with tolerated adverse reactions. Nevertheless the long-term survival benefits remain to be validated.