Definition
A circumscribed nodule of bland glands with apocrine differentiation
Diagnostic Criteria
Circumscribed nodule of tightly packed glands
Glands may have flat or papillary lining
Scant stroma
Lumenal cells show apocrine differentiation
Tall columnar
Granular eosinophilic cytoplasm
Bland, basal nuclei
Mitotic figures described in one report but absent in others
Apical blebs
Basal myoepithelial cells present
Not addressed in publications
Clearly visible in figures in de Potter 1988
Cytologically bland
Richard L Kempson MD
Original posting:: May 27, 2006
Supplemental studies
Immunohistology
No immunohistochemistry reported
Cytoplasm of lumenal cells would be expected to be GCDFP15 positive
Myoepithelial cells would be expected to be positive for myoepithelial markers
Differential Diagnosis
Sclerosing Adenosis with Apocrine Metaplasia
Apocrine Adenoma
Cellular, sclerotic stroma
Scant stroma
Small glands
Variable, larger glands
Compressed lumens
Open lumens
Apocrine Adenosis Apocrine Adenoma
Poorly circumscribed
Circumscribed nodule
Variable size and shape of glands
Uniform round glands
Usually associated with adenomyoepithelioma
No association with adenomyoepithelioma
Apocrine Carcinoma Apocrine Adenoma
Infiltrative pattern
Circumscribed
Large vesicular nuclei with prominent nucleoli
Small bland nuclei
No myoepithelial layer
Myoepithelial layer present
Clinical
Very rare, only about 6 cases reported
Half of cases reported in adult females
Single cases in adult male, juvenile male and female
Benign lesion
Grading / Staging / Report
Grading and staging are not applicable
Lists
Breast Adenomas (not all are true adenomas)
Breast Tumors and Lesions Exhibiting Reactivity for Muscle/Myoepithelial Markers
(Most benign lesions with an epithelial component will have a myoepithelial cell layer)
Bibliography
Pasquale-Styles MA, Milikowski C. Three-millimeter apocrine adenoma in a man: a case report and review of the literature. Arch Pathol Lab Med. 2003 Nov;127(11):1498-500.
Baddoura FK, Judd RL. Apocrine adenoma of the breast: report of a case with investigation of lectin binding patterns in apocrine breast lesions. Mod Pathol. 1990 May;3(3):373-6.
De Potter CR, Cuvelier CA, Roels HJ. Apocrine adenoma presenting as gynaecomastia in a 14-year-old boy. Histopathology. 1988 Dec;13(6):697-9.
Tesluk H, Amott T, Goodnight JE Jr. Apocrine adenoma of the breast. Arch Pathol Lab Med. 1986 Apr;110(4):351-2.
