Prognostic Factors of Second-line Immune Checkpoint Inhibitors in Patients With Advanced-stage Non-Small Cell Lung Cancer: A Multicenter, Retrospective Study.

Objectives: Immune checkpoint inhibitors (ICIs) targeting the programmed cell death receptor-1 and its ligand have achieved impressive success in treating patients with advanced-stage non-small cell lung cancer (NSCLC) after failed first-line cytotoxic chemotherapy. However, knowledge on clinical biomarkers that could help select patients who will respond well to second-line ICI therapy is limited.

Patients and methods: Medical records of patients with NSCLC treated with first-line platinum-based chemotherapy and subsequent second-line ICI were collected from 6 medical centers between January 2018 and June 2020. Clinical information, pathologic variables, and radiologic findings of the data collected were reviewed. The patients were followed up until the date of the last visit, the death of any cause, or the end of data recording (December 31, 2020).

Results: A total of 181 patients with NSCLC were treated with second-line ICI following first-line platinum-based doublet chemotherapy. The median progression-free survival was 2.0 months (interquartile range, 1.0 to 5.5 mo), and the median overall survival was 12.0 months (interquartile range, 6.0 to 20.0 mo). Low body mass index (BMI) was independently associated with progression-free survival (odds ratio [OR], 0.826; 95% confidence interval [CI], 0.723-0.945; P=0.005). Similarly, a low BMI (OR, 0.839; 95% CI, 0.740-0.952; P=0.005) and a high number of metastatic organs (OR, 1.682; 95% CI, 1.156-2.448; P=0.007) were independently associated with the overall survival after second-line ICI therapy.

Conclusion: BMI and the number of metastatic sites were significantly associated with second-line ICI therapy outcomes in patients with NSCLC receiving first-line platinum-based chemotherapy.