Efficacy and safety analysis of sintilimab combined with hyperthermic intraperitoneal chemotherapy as first-line treatment for advanced gastric cancer

LI Man; SHI Qingfang; GAO Jun; YANG Jun'e

doi:10.3969/j.issn.1009-0460.2025.10.011

Abstract：Objective To observe the short-term and long-term efficacy of sintilimab combined with hyperthermic intraperitoneal chemotherapy(HIPEC)as first-line treatment for advanced gastric cancer.Methods A total of 87 patients with advanced gastric cancer admitted to Hengshui People's Hospital from January 2019 to August 2020 were enrolled in this study.Based on treatment regimens,patients were divided into the combination group(n=43)and the HIPEC group(n=44).All patients received the XELOX(capecitabine/oxaliplatin)regimen.The HIPEC group additionally underwent HIPEC(containing 5-fluorouracil),while the combination group received intravenous sintilimab(200 mg per dose,once every three weeks)in addition to the HIPEC group's regimen.Therapeutic efficacy was evaluated according to the Response Evaluation Criteria in Solid Tumors version 1.1,while adverse events were graded for severity using the Common Terminology Criteria for Adverse Events version 5.0 from the National Cancer Institute.Serum levels of carcinoembryonic antigen(CEA),carbohydrate antigen 199(CA199),and carbohydrate antigen 724(CA724)were measured before and after treatment.Survival analysis was performed using the Kaplan-Meier method,with between-group comparisons conducted by the Log-rank test.Results The objective response rate(ORR)for the entire cohort of 87 patients was 51.72%(45/87).Specifically,the ORR in the combination group reached 62.79%(27/43),significantly higher than the 40.91%(18/44)observed in the HIPEC group(χ²=4.170,P=0.041).Analysis of tumor markers revealed that post-treatment serum levels of CEA,CA199,and CA724 in the combination group were(8.57±2.04)ng/mL,(194.22±45.07)mg/L,and(9.26±2.89)μg/L,respectively,all significantly lower than(12.36±3.81)ng/mL,(261.58±52.17)mg/L,and(13.47±4.45)μg/L in the HIPEC group(t=5.765,6.438,5.219,respectively;all P<0.001).Survival analysis indicated that the combination group achieved a median overall survival of 16.6 months and a 2-year survival rate of 44.19%(19/43),both significantly superior to the HIPEC group's 13.8 months and 25.00%(11/44)with a Log-rank χ² value of 5.186(P=0.023).In terms of safety,adverse reactions were predominantly grade 1-2 in both groups,with no statistically significant differences in the incidence or severity of fatigue,gastrointestinal reactions,myelosuppression,hepatorenal dysfunction,or rash(all P>0.05).Conclusion The administration of sintilimab-assisted HIPEC therapy in patients with advanced gastric cancer significantly enhances antitumor efficacy,effectively reduces serum tumor marker levels,and improves long-term survival.This treatment strategy demonstrates promising clinical application prospects and offers a new direction for comprehensive treatment of advanced gastric cancer.