Epidermoid cyst: Difference between revisions

From patholines.org
Jump to navigation Jump to search
VisualWikitext
Mikael Häggström (talk | contribs)
Administrators, Editors, Image-reviewer, csmoderator, Interface administrators, Administrators, Upload Wizard campaign editors
7,148 edits
Started
 
Mikael Häggström (talk | contribs)
Administrators, Editors, Image-reviewer, csmoderator, Interface administrators, Administrators, Upload Wizard campaign editors
7,148 edits
 
(2 intermediate revisions by the same user not shown)
Line 7: Line 7:
==Microscopic evaluation==
==Microscopic evaluation==
[[File:Histopathology of epidermoid cyst.jpg|thumb|Epidermoid cyst]]
[[File:Histopathology of epidermoid cyst.jpg|thumb|Epidermoid cyst]]
[[File:Histopathology of ruptured epidermoid cyst.jpg|thumb|A '''ruptured epidermoid cyst''', with a foreign body reaction including multinucleated giant cells, surrounding keratin fragments. A cyst wall is not necessary for diagnosis in a clinical context of skin cyst.]]
Typical findings:<ref>{{cite web|url=http://www.pathologyoutlines.com/topic/skintumornonmelanocytickeratinouscystepidermal.html|title=Skin nonmelanocytic tumor - Cysts - Epidermal (epidermoid) type|author= V. Claire Vaughan, M.D., Joshua Wisell, M.D.|website=pathology Outlines}} Topic Completed: 9 May 2019. Revised: 13 December 2019</ref>
Typical findings:<ref>{{cite web|url=http://www.pathologyoutlines.com/topic/skintumornonmelanocytickeratinouscystepidermal.html|title=Skin nonmelanocytic tumor - Cysts - Epidermal (epidermoid) type|author= V. Claire Vaughan, M.D., Joshua Wisell, M.D.|website=pathology Outlines}} Topic Completed: 9 May 2019. Revised: 13 December 2019</ref>
*Stratified squamous epithelium with a granular layer
*Stratified squamous epithelium with a granular layer
Line 12: Line 13:
*Abundant keratin flakes in cyst lumen
*Abundant keratin flakes in cyst lumen
*Often giant cell granuloma in ruptured cysts, similar to foreign body granuloma
*Often giant cell granuloma in ruptured cysts, similar to foreign body granuloma
===Differential diagnosis===
Mainly:
<gallery mode=packed heights=200>
File:Histopathology of trichilemmal cyst - annotated.jpg|'''Trichilemmal cyst''', containing, from external (top) to internal (bottom):{{MH}}<ref>{{cite web|url=https://www.medscape.com/answers/1058907-121502/which-histologic-findings-are-characteristic-of-trichilemmal-cyst-pilar-cyst|title=Which histologic findings are characteristic of trichilemmal cyst (pilar cyst)?|author=Anne Elizabeth Laumann|website=Medscape}} Updated: Jun 11, 2020,</ref><br>- Fibrous capsule<br>- Small, cuboidal, dark-staining basal epithelial cells in a palisade arrangement, with no distinct intercellular bridging<br>- Swollen pale keratinocytes, which increase in height closer to the interior<br>- Solid eosinophilic-staining keratin <br>There is no granular cell layer (in contrast to an epidermoid cyst).
File:Histopathology of pilomatricoma, high magnification, annotated.jpg|'''[[Pilomatricoma]]''': ''Stroma'' surrounding irregularly shaped islands containing ''basaloid cells'' (darkly stained, round or elongated), which abruptly or gradually transitions into ''ghost cells'' (having pale cytoplasm and a central clear area), which in turn may transition into ''necrosis''.{{MH}}<ref name=atlas>{{cite web|url=http://atlasgeneticsoncology.org/Tumors/PilomatricomaID5153.html|title=Skin: Pilomatricoma|website=Atlas of Genetics and Cytogenetics in Oncology and Haematology|date=2009-06-01|author=Punnya V Angadi}}</ref>
</gallery>
{{Further|Skin cyst}}


===Further workup===
===Further workup===
Look for signs of cyst rupture, which may manifest as inflammation, including granulomas and microabscesses.
Look for signs of cyst rupture, which may manifest as inflammation, including granulomas and microabscesses.
===Microscopic report===
Example:
{|class=wikitable
| Scalp skin cyst, excision:<br>Ruptured epidermoid cyst.
|}
{{Bottom}}
{{Bottom}}

Latest revision as of 08:42, 27 September 2021

Author: Mikael Häggström [note 1]
Generally presents as a skin cyst. Also known as epidermal inclusion cyst (EIC) and sebaceous cyst.

Microscopic evaluation

Epidermoid cyst
A ruptured epidermoid cyst, with a foreign body reaction including multinucleated giant cells, surrounding keratin fragments. A cyst wall is not necessary for diagnosis in a clinical context of skin cyst.

Typical findings:[1]

  • Stratified squamous epithelium with a granular layer
  • Cyst wall does not contain eccrine glands, sebaceous glands or hair follicles
  • Abundant keratin flakes in cyst lumen
  • Often giant cell granuloma in ruptured cysts, similar to foreign body granuloma

Differential diagnosis

Mainly:

  • Trichilemmal cyst, containing, from external (top) to internal (bottom):[image 1][2] - Fibrous capsule - Small, cuboidal, dark-staining basal epithelial cells in a palisade arrangement, with no distinct intercellular bridging - Swollen pale keratinocytes, which increase in height closer to the interior - Solid eosinophilic-staining keratin There is no granular cell layer (in contrast to an epidermoid cyst).
    Trichilemmal cyst, containing, from external (top) to internal (bottom):[image 1][2]
    - Fibrous capsule
    - Small, cuboidal, dark-staining basal epithelial cells in a palisade arrangement, with no distinct intercellular bridging
    - Swollen pale keratinocytes, which increase in height closer to the interior
    - Solid eosinophilic-staining keratin
    There is no granular cell layer (in contrast to an epidermoid cyst).
  • Pilomatricoma: Stroma surrounding irregularly shaped islands containing basaloid cells (darkly stained, round or elongated), which abruptly or gradually transitions into ghost cells (having pale cytoplasm and a central clear area), which in turn may transition into necrosis.[image 1][3]
    Pilomatricoma: Stroma surrounding irregularly shaped islands containing basaloid cells (darkly stained, round or elongated), which abruptly or gradually transitions into ghost cells (having pale cytoplasm and a central clear area), which in turn may transition into necrosis.[image 1][3]

Further information: Skin cyst

Further workup

Look for signs of cyst rupture, which may manifest as inflammation, including granulomas and microabscesses.

Microscopic report

Example:

Scalp skin cyst, excision:
Ruptured epidermoid cyst.

Notes

  1. ↑ For a full list of contributors, see article history. Creators of images are attributed at the image description pages, seen by clicking on the images. See Patholines:Authorship for details.

Main page

References

  1. ↑ V. Claire Vaughan, M.D., Joshua Wisell, M.D.. Skin nonmelanocytic tumor - Cysts - Epidermal (epidermoid) type. pathology Outlines. Topic Completed: 9 May 2019. Revised: 13 December 2019
  2. ↑ Anne Elizabeth Laumann. Which histologic findings are characteristic of trichilemmal cyst (pilar cyst)?. Medscape. Updated: Jun 11, 2020,
  3. ↑ Punnya V Angadi (2009-06-01). Skin: Pilomatricoma. Atlas of Genetics and Cytogenetics in Oncology and Haematology.

Image sources

  1. ↑ 1.0 1.1 Image(s) by: Mikael Häggström, M.D. Public Domain
    - Author info
    - Reusing images
Retrieved from "https://patholines.org/index.php?title=Epidermoid_cyst&oldid=3977"