Breast - nonmalignant
Inflammatory / infectious
Granulomatous mastitis (idiopathic)

Author: Hind Nassar, M.D. (see Authors page)

Revised: 26 July 2017, last major update January 2009

Copyright: (c) 2002-2017,, Inc.

PubMed Search: Breast [title] granulomatous mastitis (idiopathic)

Cite this page: Granulomatous mastitis (idiopathic). website. Accessed February 21st, 2018.
Definition / general
  • Diagnosis of exclusion of other granulomatous conditions
  • Also called granulomatous lobular mastitis
Clinical features
Case reports
Clinical images

Images hosted on other servers:

Appearance of second lump postbiopsy

Firm mass with multiple sinuses

Gross description
  • Firm, hard faintly nodular mass
Microscopic (histologic) description
  • Granulomatous inflammation centered on lobules with lymphocytes, plasma cells, epithelioid histiocytes, multinucleated giant cells
  • May be neutrophils; necrosis in 11%
Microscopic (histologic) images

Images hosted on PathOut server:

Inflammatory reaction in lobules with giant cells (AFIP)

Images hosted on other servers:

Various images

Nonnecrotizing granulomas with giant cells

Granulomatous inflammation centered on breast lobules

Multinucleated giant cells

Cytology description
Negative stains
  • GMS and PAS for fungi or mycobacteria
Differential diagnosis