Difference between revisions of "Dermal cysts"

From Libre Pathology
Jump to navigation Jump to search
Line 55: Line 55:


==Epidermal inclusion cyst==
==Epidermal inclusion cyst==
*Abbreviated ''EIC''.
{{Main|Epidermal inclusion cyst}}
*[[AKA]] ''epidermal cyst''.
*[[AKA]] ''epidermoid cyst''.<ref name=Ref_Derm302>{{Ref Derm|302}}</ref>
*[[AKA]] ''follicular cyst, infundibular type''.
===General===
*Very common.
*The clinical term is ''[[sebaceous cyst]]''.
**This is a misnomer as they contain keratin (not sebum).<ref name=dermis36946>URL: [http://www.dermis.net/dermisroot/en/36946/diagnose.htm http://www.dermis.net/dermisroot/en/36946/diagnose.htm]. Accessed on: 2 November 2012.</ref><ref name=pmid18201468>{{Cite journal  | last1 = Venus | first1 = MR. | last2 = Eltigani | first2 = EA. | last3 = Fagan | first3 = JM. | title = Just another sebaceous cyst? | journal = Ann R Coll Surg Engl | volume = 89 | issue = 6 | pages = W19-21 | month = Sep | year = 2007 | doi = 10.1308/147870807X227791 | PMID = 18201468 | PMC = 2121251 }}.</ref>
**The term may be used to refer to a [[pilar cyst]].
 
===Gross===
Features:<ref>URL: [http://dermatlas.med.jhmi.edu/derm/result.cfm?diagnosis=128 http://dermatlas.med.jhmi.edu/derm/result.cfm?diagnosis=128]. Accessed on: 2 November 2012.</ref>
*[[Nodule]].
*+/-Yellowish colour.
 
DDx:
*[[Pilar cyst]] - indistinguishable on gross.<ref name=dermis36946>URL: [http://www.dermis.net/dermisroot/en/36946/diagnose.htm http://www.dermis.net/dermisroot/en/36946/diagnose.htm]. Accessed on: 2 November 2012.</ref>
*[[Melanoma]].<ref name=pmid18201468/>
 
====Image====
<gallery>
Image:Inflamed_epidermal_inclusion_cyst.jpg |Epidermal inclusion cyst. (WC)
</gallery>
===Microscopic===
Features:
*Cyst lining has a granular layer - '''key feature'''.<ref>URL: [http://emedicine.medscape.com/article/1058907-diagnosis http://emedicine.medscape.com/article/1058907-diagnosis]. Accessed on: 18 March 2011.</ref>
*Trapped collagen bundles at edge of lesion with surrounded by fibroblasts.
*Keratin.
*+/-[[granuloma|Granulomatous inflammation]] due to rupture.
 
DDx:
*[[Pilar cyst]] - no granular layer.
*[[Eccrine hidrocystoma]] - eyelid lesion; same histology.<ref name=pmid10065300>{{Cite journal  | last1 = Adams | first1 = SP. | title = Dermacase. Eccrine hydrocystoma. | journal = Can Fam Physician | volume = 45 | issue =  | pages = 297, 306 | month = Feb | year = 1999 | doi =  | PMID = 10065300 |PMC = 2328272 }}</ref>
*[[Dermoid cyst]] - has adnexal structures, i.e. hair follicle, sebaceous glands, sweat glands.
*Cystic [[squamous cell carcinoma of the skin|squamous cell carcinoma]].<ref name=pmid12079164>{{Cite journal  | last1 = Lin | first1 = CY. | last2 = Jwo | first2 = SC. | title = Squamous cell carcinoma arising in an epidermal inclusion cyst. | journal = Chang Gung Med J | volume = 25 | issue = 4 | pages = 279-82 | month = Apr | year = 2002 | doi =  | PMID = 12079164 }}</ref>
*[[Keratoacanthoma]].<ref name=Ref_Derm302>{{Ref Derm|302}}</ref>
*[[Dermatofibrosarcoma protuberans]] - if lesion is large.
*Hybrid epidermoid and trichilemmal cyst.<ref name=pmid6643785>{{Cite journal  | last1 = Brownstein | first1 = MH. | title = Hybrid cyst: a combined epidermoid and trichilemmal cyst. | journal = J Am Acad Dermatol | volume = 9 | issue = 6 | pages = 872-5 | month = Dec | year = 1983 | doi =  | PMID = 6643785 }}</ref>
 
====Images====
www:
*[http://www.flickr.com/photos/euthman/5517587941/in/photostream/ Epidermal inclusion cyst (flickr.com)].
*[http://www.ajronline.org/content/184/3_supp/S47/F4.expansion.html Epidermal inclusion cyst (ajronline.org)].<ref name=pmid15728019>{{Cite journal  | last1 = Crystal | first1 = P. | last2 = Shaco-Levy | first2 = R. | title = Concentric rings within a breast mass on sonography: lamellated keratin in an epidermal inclusion cyst. | journal = AJR Am J Roentgenol | volume = 184 | issue = 3 Suppl | pages = S47-8 | month = Mar | year = 2005 | doi =  | PMID = 15728019 |URL = http://www.ajronline.org/cgi/pmidlookup?view=long&pmid=15728019}}</ref>
*[http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2627164/figure/F1/ Ruptured epidermal inclusion cyst (nih.gov)].
 
===Sign out===
<pre>
SKIN CYST, BACK, EXCISION:
- EPIDERMAL INCLUSION CYST.
</pre>
 
====Ruptured====
<pre>
SKIN LESION, RIGHT CHEEK, EXCISION:
- RUPTURED EPIDERMAL INCLUSION CYST.
</pre>
 
====Micro====
The sections show hair-bearing skin with a cyst that is lined by squamous epithelium with a granular layer.  The cyst contains keratin. The overlying epithelium is unremarkable.
 
=====Ruptured=====
The sections show hair-bearing skin with a cyst that is lined by squamous epithelium with a granular layer. The cyst contains keratin. A mixed inflammatory infiltrate (predominantly lymphocytes and plasma cells) surround the cyst. Neutrophils infiltrate the cyst lining and are admixed with the keratin within its core. 
 
The lesion appears to be completely excised in the plane of section.  Hair follicles are adjacent to the lesion; however, they are not inflamed. The overlying epithelium is unremarkable.
 
=====Ruptured without epithelium=====
The section shows a dermal collection of neutrophils with acellular keratin-like material surrounded by histiocytes and fibrosis.  The lesion is completely excised in the plane of section.  Hair follicles are adjacent to the abscess; however, they are not inflamed.


==Pilar cyst==
==Pilar cyst==

Revision as of 02:08, 31 October 2013

Dermal cysts, also skin cysts, are common in dermatopathology. Dermatopathologists can diagnose 'em.

Overview

Common types:[1]

Epidermal necrosis

Common cysts

Venous lake

General

  • Dilated vein.

Clinical:

  • Blanch with pressure.[2]

Gross

  • Purple/blue spot.

Images:

Microscopic

Features:[4]

  • Lined by endothelium.
  • Blood in lumen.
  • +/-Fibrin in lumen.
  • +/-Solar elastosis - very common.[5]

DDx:

Images:

Sign out

SKIN LESION, RIGHT CHEEK, BIOPSY:
- VENOUS LAKE.
- SOLAR ELASTOSIS.
- NEGATIVE FOR NEVUS.

Epidermal inclusion cyst

Main article: Epidermal inclusion cyst

Pilar cyst

  • AKA trichilemmal cyst.

General

  • Very common.

Gross

  • Classic location: head ~90%.[7]

Microscopic

Features:[8]

  • Keratin.
  • Cyst lining:
    • Has no granular layer - key feature.
      • Keratohyaline granules (as seen in the granular layer) may be seen focally.
    • Inner most cyst lining cells are large cells with abundant eosinophilic cytoplasm.

DDx:

Images

  • Trichilemmal cyst - intermed. mag. (WC)

  • Trichilemmal cyst - very high mag. (WC)

www:

Sign out

SCALP (CYST), EXCISION:
- TRICHILEMMAL CYST (PILAR CYST).

SKIN CYST, LEFT FLANK, EXCISION:
- TRICHILEMMAL CYST (PILAR CYST).

SCALP (CYST), ANTERIOR, EXCISION:
- TRICHILEMMAL CYST (PILAR CYST), RUPTURED.

Micro

The sections show a cyst that is lined by squamous epithelium without a granular layer. Focally, keratohyaline granules are seen in the cyst lining cells. The innermost cyst lining cells are large and have abundant eosinophilic cytoplasm. The cyst contains keratin.

Dermoid cyst

General

Microscopic

Features:[9][10]

  • Cyst lined by normal (keratinized) skin with adnexal structure (hair follicles, sweat glands, sebaceous glands).

DDx:

Images:

Sign out

OVARY AND UTERINE TUBE, LEFT, UNILATERAL SALPINGO-OOPHORECTOMY:
- MATURE TERATOMA.
- UTERINE TUBE WITHIN NORMAL LIMITS.
- NEGATIVE FOR MALIGNANCY.

Pilonidal cyst

General

  • Benign.
  • Young adults (late teens, early twenties) - usu. men.[12]

Gross

  • Usually at gluteal folds.
    • Uncommon: axilla, genital region, umbilicus, scalp.[13]

Microscopic

Features:[13]

DDx:

Sign out

SKIN LESION (PILONIDAL SINUS), EXCISION: 
- PILONIDAL SINUS.
- NEGATIVE FOR MALIGNANCY.

Micro

The section shows hair-bearing skin with a deep sinus tract containing large clusters of neutrophils, abundant plasma cells, hemosiderin-laden macrophages, eosinophils and multinucleated giant cells. The core of the lesion is, focally, well-vascularized. At the edge of the lesion is fibrotic tissue with plump fibroblasts. Benign, fibrofatty tissue with scant inflammation completely surrounds the tract, in the plane of section; however, it is focally fragmented. There is no squamous lining within the sinus. No nuclear atypia is identified.

Alternate

The section shows hair-bearing skin with a deep sinus containing large clusters of neutrophils, abundant plasma cells, hemosiderin-laden macrophages and multinucleated giant cells. Benign fibrofatty tissue with scant inflammation completely surrounds the lesion in the plane of section. There is no squamous lining within the sinus. No nuclear atypia is identified.

Less common

Steatocystoma

General

  • Benign.
  • Typically adults.
  • Usually on the trunk.
  • May be genetic; known as steatocystoma multiplex.[15]
    • Classically autosomal dominant.[16]

Microscopic

Features:[17]

  • Cyst lined by squamous epithelium with:
    1. Corrugated eosinophilic lining - key feature.
      • Similar appearance to compact keratin (hyperkeratosis).
      • Described as a hyaline cuticle.[18]
    2. No granular cell layer.

Images

  • Steatocystoma. (WC)

  • Steatocystoma - low mag. (WC/Nephron)

  • Steatocystoma - intermed. mag. (WC/Nephron)

www:

Digital mucous cyst

General

Microscopic

Features:[20]

  • Mucous in superficial dermis - key feature.
  • No epithelial lining; it is a pseudocyst.

Note:

  • Mucin = glycolated proteins; may be part of mucous.
  • Mucous = slippery secretion.
    • Some split hairs over the "u" - "mucus" vs. "mucous".[21][22]

DDx:

Images:

Sign out

LESION, LEFT INDEX FINGER, EXCISION:
- DIGITAL MUCOUS CYST.

Apocrine cystadenoma

General

  • Uncommon.

Microscopic

Features:[24]

  • Multiloculated.
  • Apocrine differentiation: columnar epithelium +/- apical snouts.
  • Solid areas of epithelial proliferation.
  • Papillary projections into the cyst.

Images:

See also

References

  1. ↑ Greenwald, J.; Heng, M. (2007). Toronto Notes for Medical Students 2007 (2007 ed.). The Toronto Notes Inc. for Medical Students Inc.. pp. D5. ISBN 978-0968592878.
  2. ↑ URL: http://dermatlas.med.jhmi.edu/derm/IndexDisplay.cfm?ImageID=-969536424. Accessed on: 13 August 2012.
  3. ↑ 3.0 3.1 3.2 URL: http://dermatlas.med.jhmi.edu/derm/result.cfm?Diagnosis=605386295. Accessed on: 13 August 2012.
  4. ↑ Weedon's Skin Pathology. 3rd Ed. P.895.
  5. ↑ 5.0 5.1 Busam, Klaus J. (2009). Dermatopathology: A Volume in the Foundations in Diagnostic Pathology Series (1st ed.). Saunders. pp. 551. ISBN 978-0443066542.
  6. ↑ URL: http://www.dermpedia.org/case/70-year-old-woman-with-nose-lesion. Accessed on: 21 June 2013.
  7. ↑ URL: http://emedicine.medscape.com/article/1058907-overview. Accessed on: 15 April 2012.
  8. ↑ Busam, Klaus J. (2009). Dermatopathology: A Volume in the Foundations in Diagnostic Pathology Series (1st ed.). Saunders. pp. 309. ISBN 978-0443066542.
  9. ↑ 9.0 9.1 9.2 Gandhi N, Syed NA, Alen R. Dermoid Cyst. EyeRounds.org. posted July 26, 2010; Available from: http://www.EyeRounds.org/cases/115-dermoid-cyst.htm. Accessed on: 22 September 2011.
  10. ↑ Mitchell, Richard; Kumar, Vinay; Fausto, Nelson; Abbas, Abul K.; Aster, Jon (2011). Pocket Companion to Robbins & Cotran Pathologic Basis of Disease (8th ed.). Elsevier Saunders. pp. 596. ISBN 978-1416054542.
  11. ↑ URL: http://emedicine.medscape.com/article/788127-overview. Accessed on: 10 September 2012.
  12. ↑ URL: http://www.nhs.uk/conditions/Pilonidal-sinus/Pages/Introduction.aspx. Accessed on: 10 September 2012.
  13. ↑ 13.0 13.1 Busam, Klaus J. (2009). Dermatopathology: A Volume in the Foundations in Diagnostic Pathology Series (1st ed.). Saunders. pp. 326. ISBN 978-0443066542.
  14. ↑ Chatzis, I.; Noussios, G.; Katsourakis, A.; Chatzitheoklitos, E.. "Squamous cell carcinoma related to long standing pilonidal-disease.". Eur J Dermatol 19 (4): 408-9. doi:10.1684/ejd.2009.0705. PMID 19482585.
  15. ↑ Online 'Mendelian Inheritance in Man' (OMIM) 184500
  16. ↑ URL: http://path.upmc.edu/cases/case674/dx.html. Accessed on: 29 January 2012.
  17. ↑ Busam, Klaus J. (2009). Dermatopathology: A Volume in the Foundations in Diagnostic Pathology Series (1st ed.). Saunders. pp. 312. ISBN 978-0443066542.
  18. ↑ URL: http://path.upmc.edu/cases/case674/dx.html. Accessed on: 29 January 2012.
  19. ↑ URL: http://path.upmc.edu/cases/case674.html. Accessed on: 29 January 2012.
  20. ↑ 20.0 20.1 20.2 20.3 URL: http://www.dermpedia.org/dermpedia-textbook/digital-mucous-myxoid-cyst. Accessed on: 17 January 2012.
  21. ↑ URL: http://dictionary.reference.com/browse/mucous. Accessed on: 8 January 2012.
  22. ↑ URL: http://dictionary.reference.com/browse/mucus. Accessed on: 8 January 2012.
  23. ↑ URL: http://www.dermpedia.org/case/digital-mucous-cyst-ganglion-type. Accessed on: 5 July 2013.
  24. ↑ Busam, Klaus J. (2009). Dermatopathology: A Volume in the Foundations in Diagnostic Pathology Series (1st ed.). Saunders. pp. 316. ISBN 978-0443066542.
Retrieved from "https://librepathology.org/w/index.php?title=Dermal_cysts&oldid=25353"