Efficacy of chemotherapy combined with immune checkpoint inhibitors for advanced non-small cell lung cancer and construction and validation of a prognostic model: a multicenter retrospective cohort study.

The goal of this multicenter retrospective cohort study was to determine the efficacy of chemotherapy in combination with immune checkpoint inhibitors (ICIs) as compared to chemotherapy alone in patients with advanced non-small cell lung cancer (NSCLC). Further, the study will assess the efficacy between the PD-1 inhibitors, evaluate independent prognostic factors and build nomogram models for predicting progression free survival (PFS) and overall survival (OS). Clinical data were retrospectively collected from patients of two centers who received first-line treatment between January 2019 and December 2023 (training cohort n=286, external validation cohort n=124). To balance baseline characteristics, propensity score matching (PSM) was adopted. Cox regression analyses were then performed to find the independent prognostic factors. After PSM (propensity score matching), a significantly higher objective response rate and disease control rate were found in the combination therapy group as compared with a single-agent therapy group (both P<0.05). The combination therapy group also exhibited a significantly longer median PFS of 10 months as compared with 6 months of single-agent therapy group; HR=1.92, P<0.001. Similarly, the combination therapy group exhibited significantly longer median OS of 21 months as compared with 12 months of single-agent therapy group; HR=2.07, P<0.001. The effectiveness of tislelizumab was similar to sintilimab in treating multiple cancers, which was further confirmed by network meta-analysis. Based on the multivariate analysis, treatment regimen, serum albumin, age, smoking status, Charlson Comorbidity Index, ECOG performance status, organ metastasis status and number of organ metastasis were independent prognostic factors for PFS, while first six variables (except smoking status and CCI) for OS. The area under the curve (AUC) values for both nomograms in internal and external validation were greater than 0.75, and they showed good calibration, good clinical utility and good risk stratification performances or capabilities. In conclusion, chemotherapy plus ICIs significantly improves short-term efficacy and long-term survival in advanced NSCLC, tislelizumab and sintilimab showed comparable efficacy, and the constructed nomograms could provide some significance for individualized clinical decision-making.