There are several types of breast cancer. The type of cell affected in the breast determines the type of breast cancer. Carcinoma- Majority of breast cancers are carcinomas which arise from epithelial cells. When the epithelial cells are from glandular tissue involving milk ducts and glands, such type of carcinoma is called as adenocarcinoma.Sarcoma -Less common types of breast cancer include sarcomas which arise from cells of connective tissue of muscle, fat or blood vessels.