CD274 and small cell lung carcinoma: Several studies (Zhou et al., 2019; Zhang L et al., 2020; Liu et al.,2021a; Ding et al., 2021; Lin et al., 2021; Wang et al., 2021; Zhu et al., 2021) evaluated the economics of PD-L1 inhibitor from a perspective outside of China showing that PD-L1 inhibitor combined with chemotherapy as the first-line regimen for ES-SCLC is not cost-effective as compared to chemotherapy, whereby the price of the PD-L1 inhibitor has a significant impact on the outcomes of the model, consistent with the findings in China.