ERBB2 and breast cancer: When we investigated whether an association exists between CD10 and the molecular subtypes of breast cancer, we found that CD10 positivity in the neoplastic cells was more frequent in triple negative (13.5%, 5/37 cases) and HER2 (18.7%, 3/16 cases) tumors compared to luminal A and B tumors (1.5%, 1/80 cases, p = 0.01).