Abstract
PURPOSE: Since mediastinal lymph node dissection and radiotherapy (RT) have potential unclear impacts on pulmonary lymphatic system, this study aimed to assess the effectiveness of immune checkpoint inhibitors (ICIs) in recurrent/metastatic non-small-cell lung cancer (NSCLC) patients who previously received radical surgery with or without thoracic RT. METHODS: Clinical data of patients who underwent pulmonary lobectomy with systematic lymphadenectomy (2000.1.1-2021.7.2) and received immunotherapy after progression were retrospectively analyzed. Efficacy was mainly evaluated based on progression-free survival (PFS) from the start of the ICIs. Toxicity was defined as treatment discontinuation due to immune-related adverse effects (irAEs). RESULTS: Ninety-five patients were enrolled in the final cohort and 30 (31.6%) patients received thoracic RT before ICI treatment. ICIs were administered as a first-line systematic treatment in 52.6% of patients. The median follow-up time was 14.7 months (95% confidence interval [CI] 13.3-18.7 months). The median PFS was 12.3 months (95% CI 8.5-36.6 months). Six (6.3%) patients had treatment suspended due to irAEs. Patients who received RT had comparable median PFS with the non-RT group (17.0 months vs. 11.1 months, p = 0.16). Similar toxicity rates were observed. Similar mPFS were reported in the stage III subgroup (RT vs. non-RT, 8.10 vs. 8.45 months, p = 0.86) or the subgroup treated by ICIs as primary systematic therapy (RT vs. non-RT, 13.6 vs. 16.1 months, p = 0.45). CONCLUSIONS: ICIs remained effective in recurrent/metastatic NSCLC patients with radical surgery and RT did not significantly compromise therapeutic effects.