Apocrine Adenoma of the Breast

Definition

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
Robert V Rouse MD
Department of Pathology
Stanford University School of Medicine
Stanford CA 94305-5342

Original posting:: May 27, 2006