A real-world retrospective study comparing the efficacy of immune checkpoint inhibitors in combination with chemotherapy versus chemotherapy alone for locally advanced gastric cancer

SHANG Chuang; LI Zhimeng; HUANG Gaofeng; WAN Xiangbin; YU Meng; QI Yapeng; ZHENG Lu

doi:10.3969/j.issn.1009-0460.2025.02.005

Abstract：Objective To retrospectively evaluate the efficacy of immune checkpoint inhibitors combined with chemotherapy compared to chemotherapy alone in patients with cT3-4 locally advanced gastric cancer,and provide valuable evidence for perioperative treatment strategies in the real-world.Methods We conducted a retrospective analysis of clinical data from 323 patients diagnosed with clinical stage T3-4NxM0 locally advanced gastric cancer at Henan Cancer Hospital between January 2020 and January 2022.Patients received either neoadjuvant chemotherapy(SOX/FOLFOX/XELOX/DOS/FLOT)or neoadjuvant immunotherapy(neoadjuvant chemotherapy plus immune checkpoint inhibitors)followed by radical gastric surgery.According to different neoadjuvant treatment regimens,the patients were divided into two groups:the chemotherapy group(242 cases)and the combined immunotherapy group(81 cases).We compared surgical outcomes and postoperative pathological responses between the two groups.Postoperative tumor regression grading(TRG)was used to evaluate postoperative pathological remission,which was divided into grades 0-4.TRG grade 0 was defined as complete pathological response(pCR),while TRG grade 0+TRG grade 1 was defined as major pathological response(MPR).Results Among 323 patients,196 patients underwent laparoscopic surgery,and 127 had open surgery,147 patients were classified as T3 stage and 176 as T4 stage preoperatively.Chi-square tests demonstrated significant differences in pathological response between the groups.In the chemotherapy-only group,24 patients achieved TRG 0(9.9％),48 TRG 1(19.8％),125 TRG 2(51.7％),and 45 TRG 3(18.6％).In contrast,the combined immunotherapy group had 21 patients with TRG 0(25.9％),15 with TRG 1(18.5％),36 with TRG 2(44.4％),and 9 with TRG 3(11.1％).There was a significant difference in the proportion of pathological remission rates between the two groups of patients(P＜0.05).The complete pathological response(pCR)rate was significantly higher in the immunotherapy group than that in the chemotherapy-only group(25.9％vs.9.9％,P＜0.05),and the MPR rate of patients in the immunotherapy group was also significantly higher than that of the chemotherapy-only group(44.4％vs.29.8％,P＜0.05).Conclusion This study provides evidence that the addition of immune checkpoint inhibitors to neoadjuvant chemotherapy significantly enhances the pathological response rate in patients with locally advanced gastric cancer in real-world study.