By immunohistochemistry, Globa et al found that the intratumoral mast cell phenotype of malignant tumor was tryptase+/chymase+/CD117+, while in the peritumoral areas three different MCs phenotypes were identified: tryptase+/chymase+/CD117-, tryptase+/CD117+/chymase- and chymase+/CD117+/tryptase- [6]. The gene discussed is KIT; the disease is cancer.