Granulomatous Lobular Mastitis

Definition

Granulomatous lobulocentric inflammation nearly always associated with a prior pregnancy

Granulomatous inflammation
- Multinucleated giant cells
- Epithelioid histiocytes
- Occasional features
  - Fat necrosis
  - Abscesses
  - Sinus tract
  - Eosinophils
- Schaumann and asteroid bodies absent to rare
Centered on lobules
- Extensive inflammation may obliterate lobulocentric character
- Ductal and periductal inflammation usually minor
Nearly always follows pregnancy
- Mean interval two years
- Rarely remote
- Has been associated with oral contraceptive use

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