CD274 and small cell lung carcinoma: A prior analysis from CASPIAN [16] demonstrated that the prevalence of PD-L1 expression on TC ≥ 1% was low in ES-SCLC, at 5.7%, but that the prevalence of PD-L1 expression on IC ≥ 1% was higher (25.8%) (Fig. 3A), resulting in an overall prevalence of PD-L1 TC and/or IC ≥ 1% of 28.3% [16].