Skin nonmelanocytic tumors
Keratinous cyst

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

Revised: 5 September 2018, last major update January 2015

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

PubMed Search: Keratinous cyst [title]

See also: epidermal, trichilemmal

Cite this page: Tranesh, G. Keratinous cyst. website. Accessed September 25th, 2018.
Definition / general
  • Cysts containing keratin and lipid debris from sebaceous secretions
  • May be painful if ruptured
  • Also called infundibular cyst; most probably arise from infundibular portion of hair follicles
  • Young and middle aged adults are most often affected
  • No gender preference
  • Face, neck, and upper trunk (may be due to damage to pilosebaceous unit)
  • Also labia majora and scrotum
Clinical features
  • Smooth dome shaped swellings, vary from a few millimeters to a few centimeters
  • Lesions of palm, sole or other sites may contain HPV 57 or 60
  • Excision if symptomatic
Clinical images

Images hosted on other servers:

Various images

Gross description
  • Cyst with creamy contents
Microscopic (histologic) description
  • Cyst containing laminated keratin
  • May have disruption of cyst wall, acute inflammation, intense foreign body giant cell reaction