Effect Of Radiotherapy On The Efficacy And Safety Of Immune Checkpoint Inhibitors Combination Therapy In Advanced Non-small Cell Lung Cancer

Objective:To evaluate the impact of radiotherapy on the efficacy and safety of immune checkpoint inhibitors(ICIs)combination therapy in patients with advanced non-small cell lung cancer(NSCLC),and explore the effect of different combined schemes of radiotherapy and immunotherapy on the efficacy of patients.Methods:The data of 152 patients with advanced NSCLC who received combined immunotherapy in the First Affiliated Hospital of Nanchang University from September 2020 to January 2022 were collected.Patients who received radiotherapy within 3 years before or during the period of immunotherapy were defined as having a history of radiotherapy.These included 61 patients with radiotherapy who were classified as the observation group and 91 patients without radiotherapy who were classified as the control group.For comparing the objective response rate(ORR),disease control rate(DCR),Progression free survival(PFS),overall survival(OS)and safety of patients between the two groups,and observing the effectiveness of different sequences,doses,and sites of radiotherapy combined with ICIs.Results:1.There was no significant difference in the ORR(44.3% vs.36.3%,p = 0.323)and DCR(95.1% vs.86.8%,p = 0.094)between the observation group and control group.However,DCR in the observation group was significantly higher versus the control group(95.7% vs.62.5%,p = 0.043)in patients with brain metastasis.2.The median PFS of the observation group and control group was 10.17 months and 5.80 months respectively(p = 0.013),and the median OS was 21.83 months and 23.73 months respectively(p = 0.815).Prognostic analysis showed that radiotherapy was an independent prognostic factor for PFS improvement(p = 0.039),and ECOG score was an independent prognostic factor for OS(p = 0.030).3.In the subgroup analysis,the time interval between radiotherapy and immunotherapy had a significant impact on the median PFS of patients(p = 0.028).The median PFS of patients with radiotherapy before immunotherapy,concurrent and after immunotherapy were 18.4 months,7.6 months and 11.43 months,respectively.The median PFS of patients who received Stereotactic radiation therapy(SRT)was significantly higher than that of patients who received conventional radiotherapy,but there was no statistical significance(12.63 vs.9.1 months,p = 0.346).The PFS of patients received lung,bone and brain irradiation were 11.33 months and 4.73 months and 13.03 months respectively(p = 0.009).4.The incidence of total adverse reactions was similar between the observation group and control group(p = 0.459),which were 86.9% and 82.3%,respectively.Conclusions:1.In patients with advanced NSCLC received combined immunotherapy,radiotherapy can significantly delay the tumor progression compared with patients who without radiotherapy with a favorable safety profile.2.The benefit for patients is superior when radiotherapy is performed before immunotherapy than when it is performed concurrent or after immunotherapy.Different irradiation sites also have a significant impact on the clinical benefit of ICIs combined with radiotherapy.