Pretreated ES-SCLC patients with a positive score receiving pembrolizumab monotherapy had better responses than PD-L1 negative patients (35.7% versus 6%), with improved survival in favor of PD-L1 positive samples (median overall survival of 14.6 months versus 7.7 months in favor of positive CPS) [36]. This evidence concerns the gene CD274 and small cell lung carcinoma.