The immunohistochemical staining of PD-L1, B7-H3, and B7-H4 for the TMAs of 115 small cell lung cancer patients and their adjacent tissues was performed, of which 1 pair of the immunohistochemical images were absent from B7-H3, and 3 pairs were absent from B7-H4. The gene discussed is CD274; the disease is small cell lung carcinoma.