Malignant Adenomyoepithelioma of Breast: A Rare and Challenging Diagnostic Entity.
- 1B.P. Koirala Institute of Health Sciences, Dharan, Sunsari, Nepal.
- 2Manipal College of Medical Sciences, Pokhara, Kaski, Nepal.
Abstract
Adenomyoepithelioma (AME) of the breast is an exceptionally rare biphasic neoplasm. Although predominantly benign, malignant AME (M-AME) presents considerable diagnostic challenges. We report a 75-year-old woman with a painless, progressively enlarging 5×5 cm left breast mass. Mammography demonstrated well-defined opacities with irregular margins and fine calcifications (BI-RADS 5), whereas core needle biopsy favored a benign lesion with epithelial and myoepithelial proliferation arranged in nests and trabeculae. Wide local excision established the diagnosis of biphasic M-AME with myoepithelial carcinoma (pT3, Nottingham Grade 2), characterized by increased mitotic activity, comedo-type necrosis, and perineural invasion. Immunohistochemistry confirmed dual epithelial and myoepithelial differentiation. Notably, the tumor demonstrated estrogen receptor positivity, an uncommon finding in M-AME. The patient subsequently underwent completion mastectomy and remains recurrence free at two-year follow-up. This case underscores the diagnostic limitations of core needle biopsy and the importance of excisional biopsy when radiologic and histopathologic findings are discordant.
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BibTeX
@article{mandal2026malignant,
title = {{Malignant Adenomyoepithelioma of Breast: A Rare and Challenging Diagnostic Entity.}},
author = {Satyam Mandal and Sandeep Kshetri and Roshan Niraula and Sangharsha Ghimire and Sagar Pokhrel},
journal = {Journal of Nepal Medical Association},
year = {2026},
month = oct,
doi = {10.31729/jnma.v64i303.9693},
url = {https://doi.org/10.31729/jnma.v64i303.9693},
note = {CC BY},
}
RIS
TY - JOUR
TI - Malignant Adenomyoepithelioma of Breast: A Rare and Challenging Diagnostic Entity.
AU - Satyam Mandal
AU - Sandeep Kshetri
AU - Roshan Niraula
AU - Sangharsha Ghimire
AU - Sagar Pokhrel
PY - 2026
DA - 2026/10/31
JO - Journal of Nepal Medical Association
DO - 10.31729/jnma.v64i303.9693
UR - https://doi.org/10.31729/jnma.v64i303.9693
AB - Adenomyoepithelioma (AME) of the breast is an exceptionally rare biphasic neoplasm. Although predominantly benign, malignant AME (M-AME) presents considerable diagnostic challenges. We report a 75-year-old woman with a painless, progressively enlarging 5×5 cm left breast mass. Mammography demonstrated well-defined opacities with irregular margins and fine calcifications (BI-RADS 5), whereas core needle biopsy favored a benign lesion with epithelial and myoepithelial proliferation arranged in nests and trabeculae. Wide local excision established the diagnosis of biphasic M-AME with myoepithelial carcinoma (pT3, Nottingham Grade 2), characterized by increased mitotic activity, comedo-type necrosis, and perineural invasion. Immunohistochemistry confirmed dual epithelial and myoepithelial differentiation. Notably, the tumor demonstrated estrogen receptor positivity, an uncommon finding in M-AME. The patient subsequently underwent completion mastectomy and remains recurrence free at two-year follow-up. This case underscores the diagnostic limitations of core needle biopsy and the importance of excisional biopsy when radiologic and histopathologic findings are discordant.
SN - 0028-2715
SN - 1815-672X
ER -