Skin - Nonmelanocytic tumors

Author: Ghassan Tranesh, M.D. (see Authors page)
Editor: Hong Qu, M.D.

Revised: 4 October 2016, last major update December 2014

Copyright: (c) 2002-2016,, Inc.

PubMed Search: Cystadenoma [title] skin

Cite this page: Cystadenoma. website. Accessed October 26th, 2016.
Definition / General
  • Also called cutaneous ciliated cyst, cutaneous müllerian cyst
  • Usually extremities of teenage girls
  • May have Mullerian derivation in females, distinct fetal eccrine duct origin in males
  • Solitary lesion which presents shortly after menarche on limb of young females (12-42 years)
  • Also described in males and at atypical sites including back, shoulder, scalp, cheek
  • Thigh > buttock > calf > foot
  • Lesions on limbs of young females are generally thought to be of müllerian (paramesonephric) derivation, representing a migration abnormality of fetal development (heterotopia)
  • Cysts arising at other sites and in males may represent metaplasia of lining of a pre-existent simple cyst of sweat duct derivation, or have an entirely different histogenesis
Clinical Features
  • Located in deep dermis or subcutaneous tissue
  • Usually asymptomatic
Case Reports
  • Surgical excision
Gross Description
  • Soft to cystic, solitary, movable, nontender, fluctuant swelling
Gross Images

Images hosted on other servers:

Round cyst with blue hue

Micro Description
  • Unilocular or multilocular cyst with intraluminal papillary projections of lining resembling fallopian tube
  • Cuboidal to columnar ciliated epithelium with frequent pseudostratified foci
  • Deep to the epithelium lie well-vascularized parallel bundles of collagen, but smooth muscle is not present
  • Occasional: squamous metaplasia, intercalated dark cells
  • Rare: mucin-secreting cells, apocrine-like features
Micro Images

Images hosted on other servers:

Epithelium-lined cyst in subcutaneous tissue

Cilia on luminal border

Thin-walled cyst

Focal squamous metaplasia

Cytokeratin+, EMA+



PR+, ER+



Positive Stains
Electron Microscopy Description
  • Ultrastructurally, cilia have characteristic morphology with a central pair of microtubules, nine radially orientated pairs of microtubules, basal bodies, cross-striated rootlets