With regard to histological types, P-cadherin is commonly identified in canine mammary carcinosarcoma and spindle cell carcinoma subtypes, as well as in human breast medullary and metaplastic carcinomas, which evokes for a basal/myoepithelial cell histogenetic origin or line of differentiation for these tumours [38, 79, 80]. This evidence concerns the gene CDH3 and neoplasm.