The NIPRO study: an observational, retrospective, multicenter study on the safety of the radiotherapy and immunotherapy combination for advanced-stage NSCLC: Immuno-Radiotherapy treatment in Advanced NSCLC

ABSTRACT Introduction : In this observational, retrospective, multi-center study, we aim to assess the safety of the combination of local metastasis-directed radiotherapy (RT) and immunotherapy in a cohort of advanced NSCLC (aNSCLC) patients. Material and Methods : We collected clinical data of aNSCLC patients who received concomitant RT and anti-PD1/PD-L1 inhibitors in seven Italian centers from September 2015 to June 2019. Concomitant RT was defined as delivered ≤4 weeks before or after the first/last administration of immunotherapy (IT), or within 2 consecutive cycles of ICI. All adverse events (AEs) apparently related to RT and/or IT were graded according to the CTCAE criteria version 4.0, and reported in terms of incidence and severity as immune-related or RT-related, or combined. Results : We analyzed the clinical charts of 187 patients. Median follow-up time was 23 months, and median OS 16.5 months (range 3-162). Thirteen patients developed pure RT-related side effects, and 43 (23.9%) developed immune-related side effects. No additive toxic effects were observed. A case of grade 5 pulmonary toxicity was recorded as a possible consequence of a combined effect. Conclusions : This analysis suggests that the combination of concomitant RT and anti-PD-1/PD-L1 agents is safe, and the two toxicity profiles are independent. MICRO-ABSTRACT This study aims to evaluate the tolerability of combination between radiotherapy and immunotherapy for patients with advanced lung cancer. We retrospectively analyzed data of 187 patients who received the combined treatment in seven Italian centers from September 2015 to June 2019. After a median follow up of 23 months, the majority of patients recovered from the adverse events. One patient experienced a grade 5 lung toxicity. Our analysis revealed a safety profile of the association of immunotherapy and radiotherapy.