CD274 and small cell lung carcinoma: Median OS, defined as the time from initial SCLC diagnosis to death, was 19.4 months (95% CI, 13.3−28.0 months) in patients with PD-L1–positive tumors and 7.5 months (95% CI, 3.0−10.9 months) in patients with PD-L1–negative tumors.