Efficacy and safety of combining radiotherapy with immune checkpoint inhibitors in patients with advanced non-small cell lung cancer: a real-world study

Background: The significance of local radiotherapy (RT) in advanced non-small-cell lung cancer (NSCLC) is well documented. However, the advent of immunotherapy has raised questions regarding the synergistic survival benefits or potential adverse effects. Objective: This study aimed to explore whether a combination of RT and systematic immune checkpoint inhibitors (ICIs) can improve the survival outcomes for NSCLC patients. Methods: Based on collected data patients who received RT were defined as the RT group, and those who had not for any site were defined as the non-RT group. Propensity score matching (PSM) was employed to mitigate bias. The primary endpoint was progression-free survival (PFS), with secondary endpoints including overall survival (OS) and treatment-related adverse events (AEs). Results: Out of 709 patients (235 in RT group and 474 in non-RT group) were included, with 213 patients per group. The median PFS of the RT group was better than that of the non-RT group (13.8 months versus 9.5 months; p < 0.0001), although no superiority in median overall survival (OS) of the RT group was observed (p = 0.715). However, among the cohort of patients with <= 3 metastases, the median OS of the RT group improved significantly (HR = 0.60, [95% CI 0.44-0.83]; p = 0.004). Treatment-related AEs occurred in 94.5% of RT group patients and in 94.9% of non-RT group patients (p = 0.792), which indicated no observable increase in AEs from RT. Conclusions: These results demonstrate the tolerability of RT when administered along with immunotherapy, suggesting its potential to positively impact the survival outcomes of NSCLC patients.