breast cancer (MONDO_0007254) is a primary or metastatic malignant neoplasm involving the breast. The vast majority of cases are carcinomas arising from the breast parenchyma or the nipple. Malignant breast neoplasms occur more frequently in females than in males. Also known as: BC, cancer of breast, malignant breast neoplasm, malignant breast tumor, malignant breast tumour, malignant neoplasm of breast, malignant neoplasm of the breast, malignant tumor of breast.