Furthermore, recent studies have shown that mast cells also affect tumor growth by enhancing angiogenesis, cancer‐cell proliferation and invasion.41 Mast‐cell infiltration of tumors predicts poor long‐term outcomes for colorectal cancer, hepatocellular carcinoma, colorectal cancer liver metastasis, and pancreatic cancer patients.42, 43, 44 Kato et al45 showed that semaphorin‐4D (Sema4D), a membrane‐bound or secreted protein involved in the regulation of antitumor immunity, was demonstrated in TILs in pancreatic cancer tissue. This evidence concerns the gene SEMA4D and familial pancreatic carcinoma.