Infiltration of lymphocytes (CD3+ or CD8+) and macrophages (CD68+ or CD163+) and expression of PD‐1/PD‐L1 were more pronounced in poorly differentiated neuroendocrine carcinoma compared to well‐differentiated neuroendocrine tumors, while CD68 and PD‐L1 correlated with advanced disease stage. Here, CD274 is linked to neuroendocrine neoplasm.