PD-L1 immunohistochemistry testing was performed in 66 patients with primary bone sarcoma and 54 patients with STS, and the positive rate of PD-L1 expression was 33.3% and 35.2% in bone sarcomas and STS, respectively, with no statistically significant differences (p = 0.83, Figure 5B). The gene discussed is CD274; the disease is bone sarcoma.