Abstract

Colonization of mammary cancers by melanocytes with heavy pigmentation of cancer cells by melanin can occur very rarely. It is not certain which mechanism operates to achieve this transfer. However, the melanocytes might inject melanin through their dendritic processes or alternatively, the cancer cells phagocytose the terminal parts of the dendritic processes with subsequent dispersal of the contained melanin contained melanin granules. We report a case of infiltrating ductal carcinoma of breast with melanocyte colonization and pigmentation in a 59-year old female.