Breast - nonmalignant
Benign tumors / changes
Inflammatory myofibroblastic tumor

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

Revised: 20 August 2018, last major update April 2010

Copyright: (c) 2002-2018,, Inc.

PubMed Search: Inflammatory myofibroblastic tumor breast

Cite this page: Nassar, H. Inflammatory myofibroblastic tumor. website. Accessed September 22nd, 2018.
Definition / general
  • Tumor of myofibroblastic spindle cells and inflammatory cells
  • Also called inflammatory pseudotumor, plasma cell granuloma
  • Extremely rare in breast with < 20 cases reported
Radiology images

Images hosted on PathOut server:

Contributed by Dr. Mark R. Wick:


Case reports
Gross description
  • Firm, circumscribed, yellow
Microscopic (histologic) description
  • Nodular with fibrovascular stroma containing myofibroblast-like cells and lymphoplasmacytic infiltrate
  • May have primarily inflammatory features (diffuse lymphoplasmacytic infiltration and lymphoid follicles), resemble myofibroblastic tumors or be hypocellular (scar-like)
  • Often mixed patterns (Am J Clin Path 1988;90:627)
Microscopic (histologic) images

Images hosted on PathOut server:

Contributed by Dr. Mark R. Wick:

Images hosted on other servers:

Myoblastic spindle cells and inflammatory cells

Various images


Cytology description
  • Inflammatory lesion with occasional aggregates of cellular connective tissue fragments, sheets of uniform ductal epithelial cells with myoepithelial cells, spindle cells, lymphocytes and histiocytelike cells (Acta Cytol 2003;47:1077)
Positive stains
Molecular / cytogenetics description
Differential diagnosis