Local consolidative therapy for synchronous oligometastatic non-small cell lung cancer treated with first-line pembrolizumab: A retrospective observational study

Background Local consolidative therapy (LCT) has emerged as a treatment option in patients with oligometastatic non-small cell lung cancer (NSCLC) undergoing chemotherapy or targeted therapy. However, the current literature lacks evidence as to whether LCT improves survival in NSCLC patients receiving immunotherapy. Our study aimed to assess whether LCT combined with pembrolizumab +/- chemotherapy could improve the survival of patients with synchronous oligometastatic NSCLC. Methods Patients with NSCLC, without EGFR or ALK genetic aberrations, who were treated with first-line pembrolizumab +/- chemotherapy, were included in the study. Survival analysis of the LCT and non-LCT groups was compared. Results A total of 231 patients were included in the study. The median follow-up time was 15.24 months. Median progression-free survival (PFS) and overall survival (OS) of the entire cohort were 12.00 and 23.43 months, respectively. Of the 231 patients included, 76 patients received LCT combined with pembrolizumab +/- chemotherapy (LCT group) while 155 patients received pembrolizumab +/- chemotherapy alone (non-LCT group). Of note, the PFS of the LCT and non-LCT groups was 13.97 and 10.08 months (p = 0.016), respectively. The OS were 30.67 and 21.97 months (p = 0.011), respectively. The PFS and OS were significantly improved with LCT for patients with brain or lung metastases but not bone metastases. No significant increase in treatment-related toxicity was observed in the LCT group. Conclusions The present study shows that LCT to metastatic sites is an option for consideration in patients with synchronous oligometastatic NSCLC during first-line pembrolizumab treatment, with significantly improved PFS and OS compared with systemic treatment alone.