Breast - nonmalignant
Adenomyoepithelial adenosis

Author: Jaya Ruth Asirvatham, M.B.B.S., M.D. (see Authors page)
Editor: Julie M. Jorns, M.D.

Revised: 2 August 2017, last major update November 2014

Copyright: (c) 2002-2017,, Inc.

PubMed Search: Adenomyoepithelial adenosis

Cite this page: Adenomyoepithelial adenosis. website. Accessed October 19th, 2018.
Definition / general
  • Uncommon variant of adenosis with proliferation of epithelial and myoepithelial cells
Clinical features
Radiology description
  • No specific features
  • May show focal asymmetry, irregular margins or microcalcification and mimic malignancy
Case reports
  • Excision recommended due to possibility of recurrence and association with malignancy
  • Best predictors of recurrence are initial incomplete excision and close margins
Radiology images

Images hosted on other servers:

Left breast

Hypoechoic mass

Irregular spiculated dense mass

Spiculated hypoechoic mass

Microscopic (histologic) description
  • Multiple foci of haphazardly arranged ducts with eosinophilic granular secretions
  • Lined by cuboidal to columnar cells surrounded by hyperplastic myoepithelial cells
  • Resembles microglandular adenosis but with larger and more irregularly shaped glands, taller lining epithelial cells with eosinophilic granular cytoplasm and bland basal nuclei
  • May show apocrine or squamous metaplasia (Breast Care (Basel) 2008;3:427)
  • May have mild nuclear atypia
  • Rare to no mitotic activity
Microscopic (histologic) images

Images hosted on other servers:

Adenomyoepithelial adenosis

Myoepithelial cells

AE1 / AE3


Positive stains
Differential diagnosis