Pembrolizumab for First-Line Treatment of Advanced Non-Small-Cell Lung Cancer: Analysis of Prognostic Factors of Outcomes

Background: In advanced non-small-cell lung cancer, without activating mutations and with PD-L1≥50%, Pembrolizumab monotherapy is the therapeutic standard in Europe. Objective: to evaluate retrospectively the safety and the efficacy of this drug and to investigate potential prognostic factors in daily clinical practice. Methods: From September 2017 to September 2019, 205 consecutive patients from 14 Italian Medical Oncology Units were enrolled in the study. Gender, Age (> or <70 years), ECOG-PS (0-1 or 2), histology (squamous or non-squamous), presence of brain, bone and liver metastases at baseline, PD-L1 score (>90% or <90%), smoking status (never or former or current) were applied to the stratified log-rank. Cox’s proportional hazards model was used for multivariate analysis. Results: At a median follow-up of 15.2 months, median progression-free and overall survival (mPFS and mOS) were 9.2 months (95% C.I., 4.8-13.5) and 15.9 months (95% C.I., not yet evaluable), respectively. Patients with Eastern Cooperative Oncology Group performance status (ECOG-PS) 2 had mPFS of 2.8 months (95% C.I., 2.1-3.4) and mOS of 3.9 months (95% C.I., 2.5-5.3). Patients with liver metastases at diagnosis had an mPFS of 3.2 months (95% C.I., 0.6-5.8) and an mOS of 6.0 months (95% C.I., 3.7-8.4). At multivariate analysis for OS gender, ECOG-PS 2, and presence of liver metastases were independent prognostic factors. Conclusion: Patients with ECOG-PS 2 derived little benefit from the use of first-line pembrolizumab. In patients with liver metastases the association of pembrolizumab with platinum-based chemotherapy could be a better option than pembrolizumab alone.