Breast - nonmalignant
Benign tumors / changes
Pleomorphic adenoma of breast

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

Revised: 11 August 2017, last major update April 2010

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

PubMed Search: Pleomorphic adenoma [title] breast

Cite this page: Nassar, H. Pleomorphic adenoma of breast. PathologyOutlines.com website. http://pathologyoutlines.com/topic/breastmixedtumor.html. Accessed November 18th, 2017.
Definition / general
  • Tumor with benign epithelial and stromal components similar to counterpart elsewhere but rare in breast
Terminology
  • Also called mixed tumor, chondroid syringoma (in skin)
Epidemiology
  • Rare in humans in breast ( < 100 cases reported, usually postmenopausal women)
Etiology
  • May derive from a single cell with divergent differentiation and not really be "mixed"
Radiology images

Images hosted on PathOut server:

Mammogram, contributed by Dr. Mark R. Wick

Case reports
Treatment
Gross description
  • Circumscribed, single or multiple yellow white firm nodules, 1 - 4 cm
  • Often subareolar
Microscopic (histologic) description
  • Similar to counterpart in salivary glands or skin (Am J Surg Pathol 1990;14:913)
  • Fibrous pseudocapsule surrounds benign glandular epithelial and myoepithelial cells in chondromyxoid or osseous stroma
  • Epithelial cells are arranged in tubules, islands, cords or sheets, are cuboidal or columnar with bland nuclear features and minimal mitotic figures
  • Myoepithelial cells are polygonal or stellate with clear to eosinophilic cytoplasm and small nuclei
Microscopic (histologic) images

Images hosted on PathOut server:

Parenchyma, contributed by Dr. Mark R. Wick

Breast skin, contributed by Dr. Mark R. Wick

Fibrosis, dilated ducts and chondroid metaplasia



Images hosted on other servers:

Fibrosis, dilated ducts and chondroid metaplasia

Cytology images

Images hosted on PathOut server:

FNAB, contributed by Dr. Mark R. Wick



Images hosted on other servers:

Hypercellular smears with cohesive fragments

Positive stains
Electron microscopy description
  • Intermediate filaments with dense bodies and intercellular junctions
Molecular / cytogenetics description
Differential diagnosis