Breast - nonmalignant
Benign tumors / changes
Cellular fibroadenoma of breast

Editorial Board Member: Emily S. Reisenbichler, M.D.

Topic Completed: 1 March 2017

Revised: 16 January 2019

Copyright: (c) 2002-2019, PathologyOutlines.com, Inc.

PubMed Search: Cellular (juvenile) fibroadenoma of breast
Page views in 2018: 8,698
Page views in 2019 to date: 3,396
Cite this page: Roychowdhury M, Nassar H Cellular fibroadenoma of breast. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/breastfibroadenomacellular.html. Accessed April 20th, 2019.
Definition / general
  • Resembles fibroadenoma with pericanalicular pattern but more cellular
Essential features
  • Fibroadenoma (stromal and epithelial process) with uniform epithelial and stromal hypercellularity but lacking leaf-like pattern of phyllodes tumor
  • No atypical features, i.e. no periductal stromal condensation, no cytologic atypia, no mitotic figures > 3/10 HPF
  • Excision is curative
Terminology
  • Also called juvenile fibroadenoma
  • Giant fibroadenoma: terminology used inconsistently; refers to size, often children but not a distinct histopathologic entity
Epidemiology
  • Usually black females, median age 15 years (range 10 - 39 years)
Clinical features
  • Grows rapidly but benign behavior
  • Often massive size
  • Either solitary or multiple / successive lesions; recurrences usually cease in 20's
  • Not associated with subsequent carcinoma
Case reports
Treatment
Gross description
  • Yellowish tan, softer than classic fibroadenoma
Gross images

Images hosted on other servers:

Well circumscribed
lobulated mass

Microscopic (histologic) description
  • Resembles fibroadenoma with pericanalicular pattern, may be mixed with intracanalicular pattern
    • Uniformly hypercellular stroma, no atypical features; i.e. no periductal increase in cellularity, no stromal overgrowth, no cytologic atypia, no mitotic figures > 3/10 HPF
    • Frequently epithelial as well as myoepithelial hyperplasia
  • Stromal and epithelial balance is not altered; lacks leaf-like growth pattern
  • Epithelium may have tufted pattern or hyperplasia characteristic of gynecomastia; may have epithelial atypia (Am J Surg Pathol 1987;11:184)
  • No increase in periductal cellularity that is seen in phyllodes tumors
Microscopic (histologic) images

Contributed by Debra L. Zynger, M.D.

Cellular fibroadenoma




Images hosted on other servers:

Juvenile fibroadenoma

Juvenile fibroadenoma - stromal and epithelial hyperplasia

Mitosis - infrequent finding


Fibroepithelial tumor with florid intraductal epithelial hyperplasia

(Myo)fibroblastic stroma, duct with columnar epithelium

Positive calponin

p63

Cytology images

Images hosted on other servers:

Monolayered sheets of ductal cells

Monolayered sheets of epithelial cells

Differential diagnosis
  • Hamartoma: more abundant adipose tissue; epithelial component is more disorganized
  • Phyllodes tumor: prominent stromal overgrowth, intracanalicular growth pattern, periductal concentration of cells, variable atypia and mitotic figures
Board review question #1
Which feature supports a diagnosis of phyllodes tumor over cellular fibroadenoma?

  1. Epithelial tufting or hyperplasia
  2. Pericanalicular pattern
  3. Periductal condensation of stromal cells
  4. Young patient
Board review answer #1
C. Periductal condensation of stromal cells; features supporting a diagnosis of phyllodes tumor over cellular fibroadenoma are an older patient, intracanalicular pattern with leaf like formations, periductal condensation of stromal cells, cytologic atypia and increased mitotic activity
Back to top