Analysis Of The Efficacy And Prognostic Biomarkers Of Immune Checkpoint Inhibitors Combined With Chemotherapy In Advanced Gastric Cancer

Objective: Immune checkpoint inhibitors(ICIs)have become another method for the treatment of gastric cancer because of its obvious and lasting effect and few side effects.Some basic studies have shown that chemotherapy and ICIs have synergistic antitumor effects.The goal of this study was to analyze the current status of ICIs combined with chemotherapy in advanced gastric cancer.In addition,we hope to obtain simpler and faster biological indicators that would make it more economical to screen out those who would benefit from treatment.Methods: The clinical data of 120 patients with advanced gastric cancer treated with chemotherapy or ICIs plus chemotherapy were retrospectively analyzed,and the efficacy[index included objective response rate(ORR),disease control rate(DCR)and progression free survival(PFS)]and adverse reaction were observed.Results: Among 120 patients,62 patients received chemotherapy alone and 58 received chemotherapy combined with ICIs.Among the 62 patients receiving chemotherapy,no patients achieved CR,6 patients had PR,47 patients had SD,and 9 patients had PD.The overall ORR was 9.7% and the DCR was 69.4%.Among the 58 patients receiving chemotherapy plus ICIs,no patients achieved CR,16 patients had PR,39 patients had SD,and 3 patients had PD.The overall ORR was 27.5% and the DCR was 94.8%.PFS of chemotherapy plus immunotherapy was significantly better than chemotherapy alone(P<0.05),and the median PFS of the two were 7.17 months(95%CI,5.85 to 8.49)and5.33 months(95%CI,3.96 to 5.70),respectively.In particular,we analyzed the situation when both treatments were the first-line option,and chemotherapy plus ICIs also provided patients with superior PFS compared to chemotherapy alone with a 37%reduction in the risk of progression versus chemotherapy alone(HR 0.63 [95% CI 0.41–0.98];P <0.05;Figure 4B).And the incidence of adverse reactions is controllable.In the chemotherapy plus ICIs group,high prognostic nutritional index(PNI)level also provided superior PFS in patients with a 47% reduction in the risk of progression versus low PNI level(HR 0.53 [95% CI 0.30–0.96];P <0.05).Median PFS was 7.47 months(95% CI 5.83–9.11)with high PNI level versus 6.00 months(4.45–7.55)with low PNI level.But the difference was not apparent in the chemotherapy group alone(P = 0.430).Similarly,NLR levels did not show good predictability in either set of data(P=0.998 in chemotherapy plus ICIs group and P=0.237 in chemotherapy group alone).18 patients treated with chemotherapy and ICIs developed adverse reactions,mainly capillary hyperplasia and myelosuppression,which improved after clinical treatment.Conclusion: The efficacy of ICIs combined with chemotherapy in patients with advanced gastric cancer is better than that of chemotherapy,and the adverse reactions are controllable.When both are used as first-line treatment,patients with gastric cancer who received chemotherapy plus ICIs also had longer PFS.In the chemotherapy plus ICIs group,patients with high PNI levels achieved higher PFS.In the chemotherapy group,13 patients developed adverse reactions,mainly nausea and vomiting and myelosuppression.