Secretory Carcinoma of the Breast

Definition

A rare (<1%) low grade breast carcinoma composed of cells with abundant granular or clear vacuolated cytoplasm

Abundant granular cytoplasm or clear vacuolated cytoplasm
Tubule formation common, may have secretion in lumens
- Follicular pattern (thyroid-like) may be seen
Secretory material in cells, lumens and stroma
- Mucicarmine, alcian blue and PAS positive, diastase resistant
- May have extracellular secretion
Fibrous bands often prominent
Low grade nuclear cytology
- Bland, uniform nuclei
- Mitotic figures rare
Sheet-like growth with mainly circumscribed margins
- Occasional foci of infiltration are common
Most common under age 30
- Most common type of breast carcinoma in children
- May occur at any age
In situ component is common

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

Original posting: May 15, 2006