Breast nonmalignant
Benign tumors
Apocrine adenoma

Topic Completed: 1 January 2016

Revised: 31 May 2019

Copyright: 2002-2019,, Inc.

PubMed Search: Breast [title] apocrine adenoma

Monika Roychowdhury, M.D.
Page views in 2018: 2,251
Page views in 2019 to date: 1,337
Cite this page: Roychowdhury M Apocrine adenoma . website. Accessed July 19th, 2019.
Definition / general
  • Adenoma with apocrine cytology throughout
  • Rare adenoma that is:
    • Composed exclusively of benign apocrine cells (homogeneous)
    • Sharply demarcated from surrounding breast tissue
    • Contains only epithelial proliferative elements
    • Has minimal supportive stroma
Essential features
  • Nodular mass composed exclusively of apocrine cells without cytological atypia
  • Sharply demarcated from adjacent breast tissue and has minimal stromal component if any
  • Considered benign, excision is curative
  • Cytological atypia, necrosis and invasive features suggest atypical hyperplasia / apocrine malignancy (DCIS / invasive), recommend careful evaluation of the entire lesion
  • Pure breast adenomas with apocrine differentiation were first described by Hertel et al. in 1976 (Cancer 1976;37:2891)
  • May represent nodular sclerosing adenosis with apocrine differentiation
Clinical features
  • Can present as a mass
Prognostic factors
  • Generally accepted to be benign, however, the number of cases reported is not sufficient to determine the level of risk associated (J Clin Pathol 2007;60:1313)
Case reports
  • Complete excision is curative
Microscopic (histologic) description
  • By definition, composed exclusively of benign apocrine cells (homogeneous), sharply demarcated from surrounding breast tissue, containing only epithelial proliferative elements, with minimal supportive stroma
  • Localized nodular focus of tubular, papillary and cystic apocrine metaplasia; benign glands have abundant granular eosinophilic cytoplasm, apical luminal blebs and decapitation secretion
  • May contain calcifications (Pathology 2001;33:149)
Microscopic (histologic) images

Images hosted on other servers:
Missing Image Missing Image

Apocrine adenoma

Missing Image Missing Image Missing Image Missing Image

Apocrine adenoma (6 mm tumor)

Missing Image

Apocrine adenoma (well circumscribed)

Missing Image Missing Image Missing Image Missing Image

Tubular apocrine adenoma, skin

Cytology description
  • Can be cuboidal or flattened, two distinct types seen:
    • Cytoplasm granular and strongly eosinophilic, supranuclear vacuole containing yellow brown pigment (rich in iron / hemosiderin)
      • Globoid and pale nuclei with 1 - 2 prominent nucleoli (nuclei may become hyperchromatic in flattened epithelium as in tension apocrine cysts)
    • Cytoplasm distinctly foamy with small vacuoles that may coalesce and show lipofuscin pigment in cytoplasm
      • Central nuclei with 1 - 2 prominent nucleoli
  • Recommend caution to exclude apocrine DCIS or invasive apocrine carcinoma if necrosis / atypia / mitosis present
Positive stains
Negative stains
Differential diagnosis
Back to top