The efficacy and safety of immune checkpoints inhibitors plus radiotherapy as a combination therapy for advanced non-small cell lung carcinoma: a meta-analysis

Abstract BackgroundImmune checkpoint inhibitors have showed good efficacy in advanced non-small-cell lung cancer(NSCLC). This meta-analysis was conducted to explore the therapeutic efficacy and safety of immune checkpoint inhibitors combined with radiotherapy for patients with advanced NSCLC.MethodsWe used many proper keywords to perform a systematic search in databases and performed a meta-analysis of trials that conducted immune checkpoint inhibitors plus radiotherapy as a treatment for advanced non-small-cell lung cancer. The outcomes included objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS), overall survival (OS) and treatment-related adverse events. A fixed-effect or random-effects model was adopted depending on between-study heterogeneity.ResultsTen trials were finally included in this meta-analysis. The combined ORR and DCR was 34% (19%-49%) and 72% (65%-79%). The combined six-month progression-free survival rates (PFSR6m) and one-year overall survival rate(OSR1y) were 50.0% (29.4%-72.8%) and 59.0% (48%-69%). Immune checkpoint inhibitors plus radiotherapy was significantly associated with improvement of PFS (hazards ratio [HR], 0.64; 95% CI 0.46–0.90; P = 0.01), OS (HR, 0.62; 95% CI 0.46–0.85; P = 0.003). In subgroup analyses, the combined ORR was 31.5% (16.4%-46.6%), combined DCR was 72.1% (63.3%-80.9%), combined PFS6m was 50.0% (20.6%-79.5%) and combined OSR1y was 59.7% (48.1%-71.2%) for anti-PD-1/PD-L1 antibody plus radiotherapy. The combined ORR was 19.5% (9.1%-29.8%) for anti-CTLA4 antibody plus radiotherapy. The combined PFS6m and OSR1y were 58.9% (26.2%-91.7%) and 59.7% (29.7%-89.8%) respectively for the concurrent therapy group. And the combined PFS6m and OS1y were 55.2% (41.6%-68.8%) and 55.7% (42.1%-69.3%) for sequential therapy. For the low-dose radiotherapy group. The combined PFS6m and OS1y were 45.9% (27.0%-64.8%) and 51.6% (37.5%-65.6%). The combined PFS6m and OS1y were 71.1% (37.9%-104.4%) and 67.4% (29.2%-105.6%) separately for high-dose radiotherapy group. When using as first-line therapy. The combined ORR was 53.8% (23.6%-84.1%) and combined ORR was 76.5% (65.0%-88.1%). While as subsequent therapy, the combined ORR and DCR were 25.9% (14.7%-37.2%) and 69.9% (60.9%-78.9%). The combined PFS6m and OS1y were 51.1% (40.3%-61.9%) and 51.8% (40.9%-62.7%).ConclusionsImmune checkpoint inhibitors plus radiotherapy might be an effective and tolerable option as a treatment for advanced NSCLC.