Lactating Adenoma of the Breast
Definition
- A benign breast lesion composed of a circumscribed mass of densely packed regular round tubules with prominent secretory change
Diagnostic Criteria
- Circumscribed mass
- Sharply demarcated but no true capsule
- Densely packed, uniform, round tubules
- Two cell layers throughout
- Lumenal cells epithelial
- Ablumenal cells myoepithelial
- Mitotic figures may be frequent
- No cytologic atypia
- Secretory change prominent
- Cytoplasmic vacuoles
- Lumenal eosinophilic secretion
- Secretory changes may be less prominent if resected prepartum
- Scant stroma
- Tubular adenoma may represent the same lesion under different physiologic conditions
- Tubular adenoma has been identified in postpartum biopsies of masses that first presented during pregnancy
