Uncommon BFL including pseudoangiomatous stromal hyperplasia, lactating adenoma, adenomyoepithelioma
and tubular adenoma were also excluded due to lower numbers.
with a malignant transformation is extremely rare and when seen, is found in both ductal epithelial and MEP components.
Surgery was performed by a single surgical team, mainly consisting of Madden modified radical mastectomy (7 cases, of which in one case bilateral), simple mastectomy (2 cases--in one patient with medical contraindications for radical surgery and one patient in which extemporaneous pathologic examination suggested an intracystic papillary carcinoma but the definitive pathological diagnosis was of adenomyoepithelioma
of the breast), subcutaneous (skin-sparing) mastectomy (in one case with cribriform carcinoma in situ).
Its benign counterpart adenomyoepithelioma
is also a rare tumor of the breast reported for the first time in 1970 (2).
Thereafter, this entity was referred to as several other neoplasms including "parotid clear cell adenoma of possible myoepithelial origin" and "adenomyoepithelioma
Hemotoxylin-eosin, S100, and MA903 histologic stains identified myoepithelial nuclear and cytoplasmic elements consistent with adenomyoepithelioma
Chemically induced mammary adenomyoepithelioma
and myoepithelial tumours.
This feature raises the differential diagnosis of the papillary variant of adenomyoepithelioma
. In contrast to adenomyoepithelioma
, in papillomas the MECs are increased only focally, lack nuclear atypia, and lack mitoses.
This tumor's differential diagnoses include adenomyoepithelioma
, phyllodes tumor, adenoleiomyoma, fibroadenoma with prominent smooth muscle, fibromatosis, benign spindle cell tumor of the breast, fibrous histiocytoma, myoid hamartoma, myoepithelioma, fibromato-sis-like low-grade metaplastic carcinoma and leiomyosarcoma of the breast (9).
of the breast associated with low-grade adenosquamous and sarcomatoid carcinomas.
Other differential diagnoses in terms of the histopathologic features of MCB include myoepithelial carcinoma of the breast, myofibroblastic tumors, phyllodes tumors, primary breast sarcoma, nodular fasciitis, fibromatosis, pleomorphic adenoma, and adenomyoepithelioma