breast neoplasm malignant breast neoplasm http://purl.bioontology.org/ontology/MEDDRA/10025541 http://purl.obolibrary.org/obo/NCIT_C9335 A primary or metastatic malignant neoplasm involving the breast. The vast majority of cases are carcinomas arising from the breast parenchyma or the nipple. C50 malignant breast neoplasms malignant neoplasm of breast malignant neoplasm of the breast breast