The efficacy of PD-1/PD-L1 inhibitors in advanced squamous-cell lung cancer: a meta-analysis of 3112 patients.

We performed a meta-analysis to explore the efficacy of immunotherapy for patients with squamous non-small-cell lung cancer (NSCLC). Randomized clinical trials comparing immunotherapy with chemotherapy for advanced NSCLC patients were included. A total of 11 trials (3112 patients) were included. PD-1/PD-L1 inhibitors demonstrated significant superiority to chemotherapy in overall survival (OS) (hazard ratio [HR]: 0.74; p < 0.001) and progression-free survival (PFS) (HR: 0.66; p < 0.001) for squamous NSCLC. The OS and PFS benefits of PD-1/PD-L1 inhibitors for squamous NSCLC were similar in subgroup analyses of line settings, PD-L1 expression and different study methodologies. No advantage in OS was found in advanced squamous NSCLC patients treated with atezolizumab (HR: 0.87; p = 0.087). PD-1/PD-L1 inhibitors significantly improved OS and PFS in advanced squamous NSCLC patients when compared with chemotherapy.