Safety and efficacy of radiotherapy and PD-1/PD-L1 inhibitor + TKI for MSS/pMMR colorectal cancer with liver metastases

DING Yuxuan; GUO Lining; SHEN Jiayi; WANG Lijun

doi:10.3969/j.issn.1006-5725.2024.09.019

Abstract：Objective To observe the efficacy and safety of radiotherapy combined with programmed death receptor-1(PD-1)inhibitors and tyrosine kinase inhibitors(TKIs)for the treatment of microsatellite-stabilized(MSS)-type or mismatch-matched repair-normal(pMMR)-type colorectal cancer with liver metastases(CCLM).Methods Case data of 25 patients with MSS-type CCLM admitted to Jiangsu Provincial Cancer Hospital from April 2021 to August 2023 were retrospectively analyzed.They were divided into observation group(n = 12)and control group(n = 13).The observation group was given radiotherapy combined with PD-1 inhibitor and TKI treatment,and the control group was given TKI monotherapy.The baseline data,treatment effect,progression-free survival,and treatment-related adverse reactions of patients in the two groups were compared.Results The difference in baseline data between the two groups was not statistically significant(P＞0.05),the disease control rate(DCR)of the observation group was higher than that of the control group(P＜0.05),the progression-free survival(PFS)of the patients in the observation group was longer than that of the control group,but the difference was not statistically sig-nificant(P＞0.05),and the difference in the incidence of treatment-related adverse events(TRAE)between the two groups was not statistically significant(P＞0.05).Conclusion The treatment regimen of radiotherapy com-bined with PD-1 inhibitors and TKI drugs improved clinical efficacy and did not increase the incidence of adverse events when compared with TKI alone,which is a treatment regimen worthy of further validation.