Clinical outcomes of pembrolizumab therapy in advanced‐NSCLC patients with poor performance status (≥3) and high PD‐L1 expression (TPS ≥50%): A case series

Pembrolizumab is the standard first‐line treatment for advanced non‐small cell lung cancer (NSCLC) with programmed death‐ligand 1 (PD‐L1) expression tumor proportion score (TPS) ≥50%. The benefit of pembrolizumab in patients with advanced NSCLC and poor performance status (PS ≥3) is limited, even when the tumor is PD‐L1‐expression‐positive. We retrospectively reviewed a total of four NSCLC cases with high PD‐L1 expression (TPS ≥50%) and poor PS. The only patient with very high PD‐L1 expression (TPS 100%) responded to pembrolizumab, but none of the three patients with high PD‐L1 expression (50%–80%) responded to pembrolizumab. In conclusion, pembrolizumab can serve as a treatment option for patients with poor PS, if PD‐L1 expression TPS is 100%.