Schneider et al. validated that PD-L1 expression was associated with the presence of lymph node metastasis in head and neck squamous cell carcinoma, while Wei et al. stated that the expression of PD-L1 in liver metastases was higher than in primary tumors of colorectal cancer [19]. The gene discussed is CD274; the disease is metastatic malignant neoplasm in the lymph nodes.