Difference between revisions of "Non-malignant skin disease"

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'''Non-malignant skin disease''' is relatively common.  The pathology may or may not be specific.  Some diseases require clinical information to diagnose.
'''Non-malignant skin disease''' is relatively common.  The pathology may or may not be specific.  Some diseases require clinical information to diagnose.  


An introduction to dermatopathology is in the ''[[dermatopathology]]'' article.  [[Nevi]] (moles) and other melanocytic lesions are dealt with in the article ''[[melanocytic lesions]]''.  Inflammatory skin conditions are dealt with in ''[[inflammatory skin disorders]]''.
An introduction to dermatopathology is in the ''[[dermatopathology]]'' article.  [[Nevi]] (moles) and other melanocytic lesions are dealt with in the article ''[[melanocytic lesions]]''.  Inflammatory skin conditions are dealt with in ''[[inflammatory skin disorders]]''.
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*[[Exocytosis]] - blood cell infiltrate the epidermis.
*[[Exocytosis]] - blood cell infiltrate the epidermis.


Images:
====Images====
*[[WC]]:
<gallery>
**[http://commons.wikimedia.org/wiki/File:Dermatomycosis_-_intermed_mag.jpg Dermatomycosis - intermed. mag. (WC)].
Image:Dermatomycosis_-_intermed_mag.jpg | Dermatomycosis - intermed. mag. (WC)
**[http://commons.wikimedia.org/wiki/File:Dermatomycosis_-_high_mag.jpg Dermatomycosis - high mag. (WC)].
Image:Dermatomycosis_-_high_mag.jpg | Dermatomycosis - high mag. (WC)
**[http://commons.wikimedia.org/wiki/File:Dermatomycosis_-_gms_-_low_mag.jpg Dermatomycosis - GMS stain - low mag. (WC)].
Image:Dermatomycosis_-_gms_-_low_mag.jpg | Dermatomycosis - GMS stain - low mag. (WC)
**[http://commons.wikimedia.org/wiki/File:Dermatomycosis_-_gms_-_high_mag.jpg Dermatomycosis - GMS stain - high mag. (WC)].
Image:Dermatomycosis_-_gms_-_high_mag.jpg | Dermatomycosis - GMS stain - high mag. (WC)
*www:
</gallery>
**[http://missinglink.ucsf.edu/lm/DermatologyGlossary/img/Dermatology%20Glossary/Glossary%20Histo%20Images/tinea_pas.jpg Dermatophytosis (ucsf.edu)].<ref>URL: [http://missinglink.ucsf.edu/lm/DermatologyGlossary/tinea.html http://missinglink.ucsf.edu/lm/DermatologyGlossary/tinea.html]. Accessed on: 25 February 2013.</ref>
www:
*[http://missinglink.ucsf.edu/lm/DermatologyGlossary/img/Dermatology%20Glossary/Glossary%20Histo%20Images/tinea_pas.jpg Dermatophytosis (ucsf.edu)].<ref>URL: [http://missinglink.ucsf.edu/lm/DermatologyGlossary/tinea.html http://missinglink.ucsf.edu/lm/DermatologyGlossary/tinea.html]. Accessed on: 25 February 2013.</ref>


===Stains===
===Stains===
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==Fibroepithelial polyp==
==Fibroepithelial polyp==
*[[AKA]] ''acrochordon''.
{{Main|Fibroepithelial polyp}}
*[[AKA]] ''skin tag''.
===General===
*Benign.
*Older people.
*May be associated with pregnancy, [[diabetes]], [[intestinal polyposis]].<ref name=Ref_PCPBoD8|596>{{Ref PCPBoD8|596}}</ref>
*Can be a component of ''[[Birt–Hogg–Dubé syndrome]]''.
 
===Gross===
*Raised skin-coloured lesion.
 
Image:
*[http://commons.wikimedia.org/wiki/File:Skintagblemish.jpg Skin tag (WC)].
 
===Microscopic===
Features:
*On a stalk / epithelium on three sides.
*Benign epidermis.
 
DDx:
*Pedunculated [[seborrheic keratosis]] - typically have epidermal hyperplasia, hyperkeratosis, horn cysts.<ref name=Ref_Derm342>{{Ref Derm|342}}</ref>
*Regressing [[melanocytic lesions]].
**[[Intradermal melanocytic nevus]].
*[[Nevus lipomatosus superficialis]] - abundant adipocytes in the superficial dermis.
*[[Neurofibroma]].
 
Images:
*[http://dermatlas.med.jhmi.edu/derm/IndexDisplay.cfm?ImageID=1767547949 Fibroepithelial polyp (dermatlas.med.jhmi.edu)].<ref>URL: [http://dermatlas.med.jhmi.edu/derm/result.cfm?Diagnosis=1196583692 http://dermatlas.med.jhmi.edu/derm/result.cfm?Diagnosis=1196583692]. Accessed on: 1 September 2011.</ref>
*[http://www.surgicalpathologyatlas.com/glfusion/mediagallery/media.php?f=0&sort=0&s=20080802171929218 Fibroepithelial polyp (surgicalpathologyatlas.com)].
*[http://dermatology-s10.cdlib.org/143/case_presentations/skintags/3.jpg Inflamed fibroepithelial polyp (cdlib.org)].<ref>URL: [http://dermatology-s10.cdlib.org/143/case_presentations/skintags/allegue.html http://dermatology-s10.cdlib.org/143/case_presentations/skintags/allegue.html]. Accessed on: 9 January 2013.</ref>
===Sign out===
<pre>
SKIN ("SKIN TAG"), THIGH, REMOVAL:
- FIBROEPITHELIAL POLYP.
</pre>
 
====Micro====
The sections show a fragment of skin with epithelium on three sides.  The epithelium matures normally and is not hypertrophic.  Orthokeratosis is present. The core of the lesion has fibrous tissue.  There is no significant inflammation. No melanocytic nests are identified.
 
=====Inflamed=====
The sections show a fragment of skin with epithelium on three sides. The epithelium matures
and is acanthotic. Minimal parakeratosis is present. The core of the lesion consists of
fibrous tissue with a mild lymphocyte-predominant dermal infiltrate.  Rare siderophages are
present.
 
There is mild basal nuclear enlargement.  No significant nuclear atypia is apparent. The
dermal-epidermal interface is well-demarcated. Rare basal mitotic activity is identified.


==Actinic keratosis==
==Actinic keratosis==
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=Very common - viral=
=Very common - viral=
==Verruca vulgaris==
==Verruca vulgaris==
*[[AKA]] common wart.
{{Main|Verruca vulgaris}}
===General===
*Etiology - [[HPV]].
*Very common.
 
Notes:
*Related to [[condyloma acuminatum]].
 
===Gross===
Features:
*[[Papule]] or [[plaque]] with granular surface.
*Classic location: hand.
 
Images:
*[http://commons.wikimedia.org/wiki/File:Porea_doet_djin_wi.jpg Wart (WC)].
*[http://commons.wikimedia.org/wiki/File:Wart_ASA_animated.gif Wart - animated (WC)].
 
===Microscopic===
Features:<ref>URL: [http://missinglink.ucsf.edu/lm/DermatologyGlossary/verruca_vulgaris.html http://missinglink.ucsf.edu/lm/DermatologyGlossary/verruca_vulgaris.html]. Accessed on: 14 July 2010.</ref>
*Hyperkeratosis (more keratin - thick stratum corneum) - in "columns"; keratin in separate towers - ''not'' a flat thick sheet.
*Hypergranulosis (thicker stratum granulosum).
*''Papillomatous hyperplasia'':
**Rete ridge lengthening (~7-10x normal) and thickening.
**Rete ridge curvature toward the centre of the lesion (like the roads to the ''Palace of Versailles'') - '''important'''.
*Large blood vessels at the dermal-epidermal junction - between the rete ridges.
*+/-Viral changes - perinuclear halo, nucleus small and hyperchromatic<ref name=Ref_Derm106-7>{{Ref Derm|106-7}}</ref> - virtually '''diagnostic''' when present.
**+/-Binucleation.
 
Memory device: there is more of everything - more s. corneum, s. granulosum, s. spinosum, longer rete ridges, more (larger) blood vessels.
 
DDx:
*[[Squamous cell carcinoma of the skin|Squamous cell carcinoma]] - nuclear atypia full thickness and often more pronounced.
*Hypertrophic [[actinic keratosis]] - often accompanied by solar elastosis.
**Actinic keratosis with superimposed [[lichen simplex chronicus]].<ref name=Ref_Derm353>{{Ref Derm|353}}</ref>
*[[Seborrheic keratosis]] - may have focal clear cell changes.
*[[Condyloma accuminatum]] - genital region.
 
====Images====
<gallery>
Image:Verruca_vulgaris_-_very_low_mag.jpg | Verruca vulgaris - very low mag. (WC)
Image:Verruca_vulgaris_-_intermed_mag.jpg | Verruca vulgaris - intermed mag. (WC)
</gallery>
www:
*[http://alf3.urz.unibas.ch/pathopic/getpic-fra.cfm?id=4528 Verruca vulgaris (unibas.ch)].
 
===Sign out===
<pre>
SKIN LESION, RIGHT LOWER LEG, SHAVE BIOPSY:
- VERRUCA VULGARIS.
</pre>
 
====Micro====
The sections show skin with elongated rete ridges, acanthosis, hypergranulosis, hyperkeratosis in  vertical columns, focal parakeratosis, dilated blood vessels at the dermal-epidermal junction and koilocytic change. Mild basilar nuclear atypia is present.
 
=====Without koilocytes=====
The sections show skin with elongated rete ridges that curve toward the centre of the lesion, acanthosis, hypergranulosis, hyperkeratosis in vertical columns, and dilated blood vessels at the dermal-epidermal
junction. Minimal basilar nuclear enlargement is present.  No definite koilocytic change is
apparent.
 
No parakeratosis is identified. Mild solar elastosis is identified.  No melanocytic nests
are apparent. Mitotic activity is not apparent.


==Verruca plana==
==Verruca plana==
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Notes:
Notes:
*It differs from verruca vulgaris... (1) orthokeratosis, (2) flat surface and base.
*It differs from [[verruca vulgaris]]... (1) orthokeratosis, (2) flat surface and base.


=Less common=
=Less common=
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==Clear cell acanthoma==
==Clear cell acanthoma==
===General===
{{Main|Clear cell acanthoma}}
*Benign.
*Elderly.
*Classically on the leg.<ref name=pmid18583817>{{Cite journal  | last1 = Akin | first1 = FY. | last2 = Ertam | first2 = I. | last3 = Ceylan | first3 = C. | last4 = Kazandi | first4 = A. | last5 = Ozdemir | first5 = F. | title = Clear cell acanthoma: new observations on dermatoscopy. | journal = Indian J Dermatol Venereol Leprol | volume = 74 | issue = 3 | pages = 285-7 | month =  | year =  | doi =  | PMID = 18583817 | URL = http://www.ijdvl.com/text.asp?2008/74/3/285/41396 }}</ref>
*Rare.
*Clinically not distinct.
**Suspected clinically in only ~3% of cases.<ref name=pmid20931670>{{Cite journal  | last1 = Morrison | first1 = LK. | last2 = Duffey | first2 = M. | last3 = Janik | first3 = M. | last4 = Shamma | first4 = HN. | title = Clear cell acanthoma: a rare clinical diagnosis prior to biopsy. | journal = Int J Dermatol | volume = 49 | issue = 9 | pages = 1008-11 | month = Sep | year = 2010 | doi =  | PMID = 20931670 }}</ref>
 
===Microscopic===
Features:<ref>URL: [http://www.drmihm.com/cases/case.cfm?CaseID=45 http://www.drmihm.com/cases/case.cfm?CaseID=45]. Accessed on: 7 February 2012.</ref>
*Psoriasiform pattern - epidermal thickening ([[acanthosis]]).
*Keratinocytes:
**Pale or light pink cytoplasm (when compared to surrounding non-lesional keratinocytes).
**Separated from one another (spongiosis).
*+/-Stratum corneum [[neutrophil]]s.
 
DDx:
*[[Psoriasis vulgaris]].
 
Images:
*[http://www.drmihm.com/cases/casefigure.cfm?figID=906&CaseID=45 CCA (drmihm.com)].
*[http://www.dermatlas.com/derm/IndexDisplay.cfm?ImageID=-327718365 CCA - low mag. (dermatlas.com)].
*[http://www.dermatlas.com/derm/IndexDisplay.cfm?ImageID=546460717 CCA - high mag. (dermatlas.com)].


==Chondrodermatitis nodularis chronica helicis==
==Chondrodermatitis nodularis chronica helicis==
*[[AKA]] ''chondrodermatitis nodularis helicis''.
*[[AKA]] ''chondrodermatitis nodularis helicis''.
*Abbreviated ''CNCH''.
*Abbreviated ''CNCH''.
===General===
*[[AKA]] ''Winkler disease''.<ref>URL: [http://www.head-face-med.com/content/4/1/2 http://www.head-face-med.com/content/4/1/2]. Accessed on: 16 January 2014.</ref>
*Tender/painful - '''key clinical feature'''.
{{Main|Chondrodermatitis nodularis chronica helicis}}
*Typically right [[ear]] - people more often sleep on this one.<ref name=pmid17879469>{{Cite journal  | last1 = Devani | first1 = A. | last2 = Barankin | first2 = B. | title = Dermacase. Chondrodermatitis nodularis  chronica helicis. | journal = Can Fam Physician | volume = 53 | issue = 5 | pages = 821, 837 | month = May | year = 2007 | doi =  | PMID = 17879469 }}</ref>
*Usually >40 years old.
 
Etiology:
*Trauma/mechanical.
 
===Gross===
*[[Papule]] on ear.
*+/-Erythematous.
*+/-Crust.
 
Clinical DDx:<ref name=pmid17879469/>
*[[BCC]].
*[[SCC]].
 
Images:
*[http://commons.wikimedia.org/wiki/File:Chondrodermatitis.jpg CNCH (WC)].
*[http://www.dermnetnz.org/lesions/chondrodermatitis.html CNCH (dermnetnz.org)].
 
===Microscopic===
Features:<ref name=pmid17879469/>
*Dermal inflammation.
*Epithelial hyperlasia.
*Fibrosis.
*Cartilaginous pathology:
**Perichondrial inflammation  - '''key feature'''.
**Perichondrial disruption.
**+/-Necrosis.
**+/-Hemorrhage.
 
Images:
*[http://www.dermpedia.org/case/chondrodermatitis-nodularis-chronica-helicis CNCH (dermpedia.org)].
*[http://www.surgicalpathologyatlas.com/glfusion/mediagallery/media.php?s=20080802171837514 CNCH (surgicalpathologyatlas.com)].
*[http://dermatlas.med.jhmi.edu/derm/indexDisplay.cfm?ImageID=2140701395 CNCH (dermatlas.med.jhmi.edu)].
 
===Sign out===
====Superficial biopsy====
<pre>
SKIN LESION, LEFT ANTIHELIX OF EAR, BIOPSY:
- SUPERFICIAL SKIN WITH ACANTHOSIS, HYPERKERATOSIS, MODERATE SOLAR ELASTOSIS,
  HYPERGRANULOSIS AND A MILD LYMPHOCYTIC PERIVASCULAR INFILTRATE.
- NO CARTILAGE IS IDENTIFIED.
- NEGATIVE FOR DYSPLASIA AND MALIGNANCY.
 
COMMENT:
The findings are non-specific. Chondrodermatitis cannot be excluded.
</pre>


==Cutaneous calcinosis==
==Cutaneous calcinosis==
*[[AKA]] ''calcinosis cutis''.
*[[AKA]] ''calcinosis cutis''.
===General===
{{Main|Cutaneous calcinosis}}
*Benign in itself; underlying cause may not be benign.
*May be a [[scrotum|scrotal]] lesion - known as ''scrotal calcinosis''.<ref name=pmid20178701>{{Cite journal  | last1 = Dubey | first1 = S. | last2 = Sharma | first2 = R. | last3 = Maheshwari | first3 = V. | title = Scrotal calcinosis: idiopathic or dystrophic? | journal = Dermatol Online J | volume = 16 | issue = 2 | pages = 5 | month =  | year = 2010 | doi =  | PMID = 20178701 }}</ref>
 
Subtypes:<ref name=emed>URL: [http://emedicine.medscape.com/article/1103137-overview http://emedicine.medscape.com/article/1103137-overview]. Accessed on: 21 September 2011.</ref>
#Dystrophic - due to death of cells; may be related to a tumour.
#Metastatic - due to chronic renal failure; hyperkalemia; paraneoplastic phenomenon.
#Iatrogenic - post surgical.
#Idiopathic.
 
===Microscopic===
Features:
*Dermal calcification:
**Acellular purple blobs on [[H&E]].
***+/-Artefactual tearing of surrounding tissue due to processing (cutting).
***+/-Small artefactual lines ~1-2 micrometers due to processing (cutting).
***+/-Greyish rim of paucicellular material.
**Usu. well-circumscribed.
***May be surrounded by a palisading granuloma & [[giant cell]]s.
 
Images:
*[http://www.dermatopathonline.com/calcinosis%20cutis2.html Calcinosis cutis (dermatopathonline.com)].
 
===Sign out===
<pre>
SKIN AND SUBCUTANEOUS LESION, LEFT HIP, EXCISION:
- SUBCUTANEOUS CALCIFICATION SURROUNDED BY BENIGN FIBROUS TISSUE.
- DERMAL SCAR.
- NEGATIVE FOR MALIGNANCY.
</pre>
 
<pre>
SUBCUTANEOUS MASS, OVER BURSA OF ELBOW, EXCISION:
- CALCINOSIS CUTIS.
</pre>
 
====Micro====
The sections show subcutaneous calcifications surrounded by macrophages and giant cells. No nuclear atypia is apparent. The overlying skin is unremarkable.


==Dilated pore of Winer==
==Dilated pore of Winer==
===General===
===General===
*Benign.
*Benign.
*Looks like zit.
*Looks like a zit.


===Microscopic===
===Microscopic===
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*[[Acanthosis]].
*[[Acanthosis]].
*Budding of epidermis (into dermis).
*Budding of epidermis (into dermis).
==Lichenoid keratosis==
*[[AKA]] ''lichen planus-like keratosis''.
*[[AKA]] ''lichenoid keratosis''.
===General===
*Caucasians - middle age or older.
*May be a variant of [[seborrheic keratosis]] (with marked inflammation).<ref name=Ref_Derm346>{{Ref Derm|346}}</ref>
Clinical DDx:<ref name=Ref_Derm346>{{Ref Derm|346}}</ref>
*[[Basal cell carcinoma]], [[squamous cell carcinoma of the skin]], melanocytic neoplasm.
===Microscopic===
Features:<ref name=Ref_Derm347>{{Ref Derm|347}}</ref>
*Hyperkeratosis.
*Parakeratosis.
*Band of inflammatory cells at DE junction (lichenoid inflammation).
*Dead keratinocytes (Civatte bodies).
*Dermal melanophages.


DDx:
DDx:
*[[Lichen planus]] - need clinical correlation (mucosal lesions).
*[[Pilar sheath acanthoma]].
*[[Drug reaction]].
*[[Cutaneous T-cell lymphoma]].
*Regressed melanocytic lesion, esp. [[malignant melanoma]].
*Lichenoid [[actinic keratosis]] - has atypical hyperchromatic basal cells - esp. at edge of lesion, usu. in the context of [[solar elastosis]].


Images:
Image:
*[http://www.dermpathexpert.com/id57.html Lichenoid keratosis (dermpathexpert.com)].
*[http://dermpathexpert.com/id90.html Dilated pore of Winer (dermpathexpert.com)].


===Sign out===
==Lichenoid keratosis==
<pre>
*[[AKA]] ''lichen planus-like keratosis''.
SKIN LESION, MID-MIDDLE BACK, PUNCH BIOPSY:
{{Main|Lichenoid keratosis}}
- LICHENOID KERATOSIS.
</pre>


==Granuloma annulare==
==Granuloma annulare==
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==Necrobiosis lipoidica==
==Necrobiosis lipoidica==
===General===
{{Main|Necrobiosis lipoidica}}
Associated with:
*[[Diabetes mellitus]] - known as ''necrobiosis lipoidica diabeticorum''.
*[[Rheumatoid arthritis]].
 
===Gross===
 
Image:
<gallery>
Image:Necrobiosislipoidica.jpg | Necrobiosis lipoidica. (WC)
</gallery>
 
===Microscopic===
Features:<ref name=Ref_Derm51>{{Ref Derm|51}}</ref>
*Dermal palisading [[granuloma]] around:
**Necrotic collagen - '''key feature'''.
***Nuclei "missing" - have undergone karyolysis.
*Little mucin, no normal dermis between foci.
*Plasma cells - common.<ref name=dermnetnz_nl>URL: [http://dermnetnz.org/pathology/necrobiosis-lipoidica-path.html http://dermnetnz.org/pathology/necrobiosis-lipoidica-path.html]. Accessed on: 24 January 2012.</ref>
*May involve adipose tissue.
 
DDx:
*[[Granuloma annulare|Granuloma a'''nn'''ulare]] - '''m'''ore '''m'''ucin, normal dermis between foci,<ref name=Ref_Derm51>{{Ref Derm|51}}</ref> plasma cells uncommon,<ref name=dermnetnz_nl/> no fat involvement - usu. more superficial.
*[[Rheumatoid nodule]].
 
====Images====
<gallery>
Image:Necrobiosis_lipoidica_-_low_mag.jpg | Necrobiosis lipoidica - low mag. (WC)
</gallery>
www:
*[http://dermatology.cdlib.org/103/NYU/case_presentations/042004n10.html Necrobiosis lipoidica (dermatology.cdlib.org)].
*[http://www.drmihm.com/cases/case.cfm?CaseID=53 Necrobiosis lipoidica (drmihm.com)].
*[http://dermnetnz.org/pathology/necrobiosis-lipoidica-path.html Necrobiosis lipoidica (dermnetnz.org)].


==Keloid==
==Keloid==
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:See also: ''[[nasopharyngeal angiofibroma]]''.
:See also: ''[[nasopharyngeal angiofibroma]]''.
:Should '''not''' be confused with ''[[angiokeratoma]]''.
:Should '''not''' be confused with ''[[angiokeratoma]]''.
===General===
{{Main|Angiofibroma}}
*May be seen in the context of [[tuberous sclerosis]] - especially "butterfly area of the face".<ref name=Ref_WMSP492>{{Ref WMSP|492}}</ref>
*Solitary lesions in adults are known as ''[[fibrous papules]]'' and classically arise on the nose.<ref name=Ref_Derm505>{{Ref Derm|505}}</ref>
 
Clinical:
*Firm, dome-shaped, flesh coloured.
 
===Microscopic===
Features:<ref name=Ref_WMSP492>{{Ref WMSP|492}}</ref>
*Dome-shaped.
*Fibrotic dermis.
**Enlarged fibroblasts.
*Dilated small vessels.
 
DDx:
*[[Benign fibrous papule]] - solitary, nose lesion.
 
Image:
*[http://www.drdittmar.lu/images/sce/angiofibroma-s.jpg Angiofibroma (drdittmar.lu)].<ref>URL: [http://www.drdittmar.lu/Services.aspx http://www.drdittmar.lu/Services.aspx]. Accessed on: 1 September 2011.</ref>


==Benign fibrous papule==
==Benign fibrous papule==
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Note:
Note:
*Several variants exist.<ref name=pmid18032900>{{Cite journal  | last1 = Jacyk | first1 = WK. | last2 = Rütten | first2 = A. | last3 = Requena | first3 = L. | title = Fibrous papule of the face with granular cells. | journal = Dermatology | volume = 216 | issue = 1 | pages = 56-9 | month =  | year = 2008 | doi = 10.1159/000109359 | PMID = 18032900 }}</ref>
*Several variants exist.<ref name=pmid18032900>{{Cite journal  | last1 = Jacyk | first1 = WK. | last2 = Rütten | first2 = A. | last3 = Requena | first3 = L. | title = Fibrous papule of the face with granular cells. | journal = Dermatology | volume = 216 | issue = 1 | pages = 56-9 | month =  | year = 2008 | doi = 10.1159/000109359 | PMID = 18032900 }}</ref>
===Images===
*[http://www.dermaamin.com/site/histopathology-of-the-skin/58-f/1739-fibrous-papule-angiofibroma-.html Fibrous papule (dermaamin.com)].


===Sign out===
===Sign out===
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==Molluscum contagiosum==
==Molluscum contagiosum==
*Abbreviated ''MC''.
{{Main|Molluscum contagiosum}}
===General===
*Etiology: caused by ''molluscum contagiosum virus''.
*May be abundant in immune deficient individuals, e.g. [[HIV]]/AIDS.
 
===Gross===
Features:<ref name=Ref_Derm115>{{Ref Derm|115}}</ref>
*Dome-shaped papules, flesh coloured or pearly.
*Usually face or trunk.
*+/-Central umbilication.
**Central depression.
 
DDx - gross:
*[[Skin tag]].
 
Image:
*[http://commons.wikimedia.org/wiki/File:Molluscaklein.jpg Molluscum contagiosum (WC)].
 
===Microscopic===
Features:<ref name=Ref_Derm115>{{Ref Derm 115}}</ref>
*A suprabasilar epidermal lesion consisting of "molluscum bodies" -- in other words "molluscum bodies" are found above the stratum basale +/- extension to the skin surface.
**Molluscum bodies - '''key feature''':
***Large cells with (granular) eosinophilic cytoplasmic inclusions.
****The inclusions usually fill the cytoplasm.
****Inclusions are usually one per cell... but may be multiple.
***Small peripheral nucleus.
*+/-Lymphocytes.
 
Notes:
*Molluscum bodies very vaguely resemble ''[[signet ring cell]]s'' -- but:
**Cytoplasm is eosinophilic and granular.
**Nucleus usually smaller than in signet ring cells.
**''Molluscum bodies'' are only in the epidermis - an uncommon place to find SRCs without finding them elsewhere.
*The granular eosinophilic cytoplasmic inclusions represents accumulated virons.
*Molluscum bodies "grow" toward the surface
 
DDx:
*Nothing really - it is very distinctive.
 
Images:
*[http://commons.wikimedia.org/wiki/File:Molluscum_contagiosum_high_mag.jpg Molluscum contagiosum - high mag. (WC)].
*[http://commons.wikimedia.org/wiki/File:Molluscum_contagiosum_low_mag.jpg Molluscum contagiosum - low magnification (WC)].
*[http://commons.wikimedia.org/wiki/File:Molluscum_contagiosum_1.jpg Molluscum contagiosum (WC)].
 
===Sign out===
<pre>
SKIN LESION ("SKIN TAG"), EXCISION:
- MOLLUSCUM CONTAGIOSUM.
</pre>
 
====Micro====
The section shows fragments of skin with epithelium on three sides. Large suprabasilar cells with eosinophilic intracytoplasmic inclusions (molluscum bodies) and small eccentric nuclei are present, and extend to the skin surface. The epithelium is acanthotic; however, it matures to the surface. There is no significant inflammation.


==Superficial dermal infiltrates==
==Superficial dermal infiltrates==
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==Mastocytosis==
==Mastocytosis==
===General===
{{Main|Mastocytosis}}
*Abundance of [[mast cell]]s.
 
Classification:<ref name=pmid21083038>{{Cite journal  | last1 = Arock | first1 = M. | last2 = Valent | first2 = P. | title = Pathogenesis, classification and treatment of mastocytosis: state of the art in 2010 and future perspectives. | journal = Expert Rev Hematol | volume = 3 | issue = 4 | pages = 497-516 | month = Aug | year = 2010 | doi = 10.1586/ehm.10.42 | PMID = 21083038 }}</ref>
#Cutaneous (only) - usually children.
#*Urticaria pigmentosa.
#*Others.
#Systemic - usually adults.
#*Indolent subvariant.
#*Aggressive subvariant.
#*Leukemic subvariant.
 
===Microscopic===
Features:<ref name=Ref_PBoD8|1185>{{Ref PBoD8|1185}}</ref>
*Cells in the superficial/mid dermis that are:
**Lymphocyte-like with more cytoplasm that is granular.
***Cells may have spindled or stellate morphology.
***Tend to be more abundant around vessels.
*+/-Eosinophils (common).
*+/-Edema - often prominent; gives cells a white halo.
 
Notes:
*Lymphocyte vs. mast cell:
**Lymphocytes = round; mast cells = ovoid.
 
Images:
*www:
**[http://www.jameswpattersonmd.com/case_studies/index.cfm?CFID=387434 Mastocytosis - low res. (jameswpattersonmd.com)].
**[http://path.upmc.edu/cases/case366.html Mastocytosis - bone marrow - several images (upmc.edu)].
*[[WC]]:
**[http://commons.wikimedia.org/wiki/File:Mastocytosis_-_high_mag.jpg Mastocytosis - high mag. (WC)].
**[http://commons.wikimedia.org/wiki/File:Mastocytosis_-_cropped_-_very_high_mag.jpg Mastocytosis - very high mag. (WC)].
**[http://path.upmc.edu/cases/case409.html Systemic mastocytosis - several images (upmc.edu)].
 
===Stains===
*[[Toluidine blue stain|Toluidine blue]] -- highlights the granules.
 
===IHC===
*CD117 +ve.
*Tryptase +ve.<ref name=pmid21866466>{{Cite journal  | last1 = Rudzki | first1 = Z. | last2 = Sotlar | first2 = K. | last3 = Kudela | first3 = A. | last4 = Starzak-Gwóźdź | first4 = J. | last5 = Horny | first5 = HP. | title = Systemic mastocytosis (SM) and associated malignant bone marrow histiocytosis - a hitherto undescribed form of SM-AHNMD. | journal = Pol J Pathol | volume = 62 | issue = 2 | pages = 101-4 | month =  | year = 2011 | doi =  | PMID = 21866466 }}
</ref>


==Ichthyosis==
==Ichthyosis==
Line 789: Line 415:


==Palmar fibromatosis==
==Palmar fibromatosis==
{{Main|Fibromatosis}}
*[[AKA]] ''Dupuytren's contracture''.
*[[AKA]] ''Dupuytren's contracture''.
*[[AKA]] ''Dupuytren disease''.
*[[AKA]] ''Dupuytren disease''.
===General===
{{Main|Palmar fibromatosis}}
Clinical:<ref>URL: [http://www.humpath.com/palmar-fibromatosis http://www.humpath.com/palmar-fibromatosis]. Accessed on: 6 January 2011.</ref>
*Usually older - 60s or 70s (years old).
*Male > female.
*Associated with:
**[[Alcohol abuse]].
*May be familial.
 
===Gross===
*Ring finger - classic location.{{fact}}
*Nodular.
*Poorly demarcated.
 
Image:
*[http://commons.wikimedia.org/wiki/File:Morbus_dupuytren_fcm.jpg Palmar fibromatosis (WC)].
 
===Microscopic===
Features:<ref>URL: [http://surgpathcriteria.stanford.edu/softfib/plantar_fibromatosis/printable.html http://surgpathcriteria.stanford.edu/softfib/plantar_fibromatosis/printable.html]. Accessed on: 6 January 2011.</ref><ref name=standford_pf_ddx>URL: [http://surgpathcriteria.stanford.edu/softfib/palmar_fibromatosis/differentialdiagnosis.html http://surgpathcriteria.stanford.edu/softfib/palmar_fibromatosis/differentialdiagnosis.html]. Accessed on: 9 November 2012.</ref>
*Poorly demarcated, usu. multiple lesions/multiple nodules.
*Composed of bland spindle cells in dense collagen.
**Pale grey cytoplasm (moderate quantity).
**Pale ovoid nuclei with small round nucleoli.
*Giant cells - rare.
 
Note:
*No nuclear atypia.
*Mitotic figures - rarely present, none atypical.
*May see Pacinian corpuscle ([[AKA]] lamellar corpuscle) as an incidental finding.
 
DDx:<ref name=standford_pf_ddx>URL: [http://surgpathcriteria.stanford.edu/softfib/palmar_fibromatosis/differentialdiagnosis.html http://surgpathcriteria.stanford.edu/softfib/palmar_fibromatosis/differentialdiagnosis.html]. Accessed on: 9 November 2012.</ref>
*[[Calcifying aponeurotic fibroma]] - calcification, chondroid differentiation, usu. < 20 years old.
*Extra-abdominal desmoid [[fibromatosis]] - extremely rare on hands and feet, muscle infiltrative.
*Inclusion body [[fibromatosis]].   
*[[Fibrosarcoma]] - atypia, necrosis, herring-bone pattern.
*[[Synovial sarcoma]] - one mass.
*[[Epithelioid sarcoma]] - necrosis, atypia.
*[[metastasis|Metastatic]] metaplastic carcinoma, e.g. [[metaplastic breast carcinoma]] - extremely uncommon.
 
Images:
*[http://www.biomedsearch.com/attachments/display/00/16/69/68/16696857/1479-5876-4-21-2.jpg Palmer fibromatosis (biomedsearch.com)].<ref name=pmid16696857>{{cite journal |author=Wang L, Zhu H |title=Clonal analysis of palmar fibromatosis: a study whether palmar fibromatosis is a real tumor |journal=J Transl Med |volume=4 |issue= |pages=21 |year=2006 |pmid=16696857 |pmc=1488873 |doi=10.1186/1479-5876-4-21 |url=http://www.biomedsearch.com/nih/Clonal-analysis-palmar-fibromatosis-study/16696857.html}}</ref>
*[http://alf3.urz.unibas.ch/pathopic/e/getpic-fra.cfm?id=8235 Palmar fibromatosis (unibas.ch)].
*[http://commons.wikimedia.org/wiki/File:WVSOM_Pacinian_Corpuscle.JPG Pacinian corpuscle (WC)].
*[http://commons.wikimedia.org/wiki/File:Tendon_-_intermed_mag.jpg Tendon without fibromatosis - intermed. mag. (WC)].
 
===IHC===
*Beta-catenin +ve (cytoplasmic & nuclear).<ref name=pmid18958538>{{Cite journal  | last1 = Degreef | first1 = I. | last2 = De Smet | first2 = L. | last3 = Sciot | first3 = R. | last4 = Cassiman | first4 = JJ. | last5 = Tejpar | first5 = S. | title = Beta-catenin overexpression in Dupuytren's disease is unrelated to disease recurrence. | journal = Clin Orthop Relat Res | volume = 467 | issue = 3 | pages = 838-45 | month = Mar | year = 2009 | doi = 10.1007/s11999-008-0590-z | PMID = 18958538 }}</ref>
 
===Sign out===
====Left====
<pre>
PALMAR FASCIA, LEFT, FASCIECTOMY:
- PALMAR FIBROMATOSIS.
</pre>
 
====Right====
<pre>
PALMAR FASCIA, RIGHT, FASCIECTOMY:
- PALMAR FIBROMATOSIS.
</pre>
 
=====Micro=====
The sections show multiple poorly-demarcated nodules composed of bland spindle cells with moderate pale grey cytoplasm and pale ellipsoid nuclei with small round nucleoli. The poorly-demarcated nodules are completely surrounded by dense collagen. Calcification is not present. There is no nuclear atypia or necrosis. Mitotic activity is not identified. Benign fibroadipose tissue is present.
 
====Missed fibromatosis====
<pre>
PALMAR FASCIA, LEFT, FASCIECTOMY:
- PALMAR FASCIA WITHIN NORMAL LIMITS AND BENIGN FIBROADIPOSE TISSUE -- IN AN
  INDIVIDUAL WITH A CLINICAL HISTORY OF PALMAR FIBROMATOSIS.
- NEGATIVE FOR MALIGNANCY.
</pre>
 
======Micro======
The sections show dense collagen (tendon) without an apparent pathology. Calcification is not present. There is no nuclear atypia or necrosis. Mitotic activity is not identified. Benign fibroadipose tissue is present. Lamellar corpuscles are present. The tissue was submitted in toto and levels were cut.
 
=====Straight=====
<pre>
PALMAR FASCIA, RIGHT, FASCIECTOMY:
- PALMAR FASCIA WITHIN NORMAL LIMITS.
- NEGATIVE FOR FIBROMATOSIS.
 
COMMENT:
The tissue was submitted in toto and levels were cut.
</pre>
 
======Micro======
The sections show dense collagen (tendon) without an apparent pathology. Calcification is not present. There is no nuclear atypia or necrosis. Mitotic activity is not identified. Benign fibroadipose tissue is present. Lamellar corpuscles are present.


==Angiomyoma==
==Angiomyoma==
Line 896: Line 436:


==Angiokeratoma==
==Angiokeratoma==
===General===
{{Main|Angiokeratoma}}
*Rare.
*May be seen in the context of [[Fabry disease]].<ref name=pmid16403380/>
 
Notes:
*Shouldn't be confused with ''[[angiofibroma]]'' which is associated [[tuberous sclerosis]].
 
===Gross===
*Dark lesions.
 
Clinical DDx:
*[[Melanocytic lesions]].
====Images====
<gallery>
Image:Angiokeratoma_of_the_Scrotum_7.jpg | Angiokeratoma. (WC)
</gallery>
 
===Microscopic===
Features:<ref name=pmid16403380>{{Cite journal  | last1 = Karen | first1 = JK. | last2 = Hale | first2 = EK. | last3 = Ma | first3 = L. | title = Angiokeratoma corporis diffusum (Fabry disease). | journal = Dermatol Online J | volume = 11 | issue = 4 | pages = 8 | month =  | year = 2005 | doi =  | PMID = 16403380 }}</ref>
#Ectatic superficial dermal vessels.
#Overlying hyperkeratosis (thick stratum corneum).
*Should have "epidermal collarette".<ref name=Ref_Derm548>{{Ref Derm|548}}</ref>
**Vascular space surrounded by epidermis on three sides.
 
Others features:{{fact}}
*Irregular [[acanthosis]].
*Longer rete ridges.
 
DDx:
*[[Venous lake]].
 
====Images====
<gallery>
Image:Angiokeratoma_-_low_mag.jpg | Angiokeratoma - low mag. (WC/Nephron)
Image:Angiokeratoma_-_intermed_mag.jpg | Angiokeratoma - intermed. mag. (WC/Nephron)
</gallery>
www:
*[http://www.pathologyoutlines.com/images/skintumorangiokerat1.jpg Angiokeratoma (pathologyoutlines.com)].
 
===Sign out===
<pre>
SKIN LESION, LEFT POPITEAL FOSSA, PUNCH BIOPSY:
- ANGIOKERATOMA.
</pre>


==Inverted follicular keratosis==
==Inverted follicular keratosis==
Line 1,006: Line 503:
:'''''Not''' to be confused with [[nodular fasciitis]]''.
:'''''Not''' to be confused with [[nodular fasciitis]]''.
*[[AKA]] ''flesh-eating disease''.
*[[AKA]] ''flesh-eating disease''.
===General===
{{Main|Necrotizing fasciitis}}
*High mortality.
*May be diagnosed at [[frozen section]].<ref name=pmid9386043>{{Cite journal  | last1 = Majeski | first1 = J. | last2 = Majeski | first2 = E. | title = Necrotizing fasciitis: improved survival with early recognition by tissue biopsy and aggressive surgical treatment. | journal = South Med J | volume = 90 | issue = 11 | pages = 1065-8 | month = Nov | year = 1997 | doi =  | PMID = 9386043 }}</ref>
*Classically associated with ''Group A streptococcus''.
 
Treatment:
*Operative debridement.
 
===Microscopic===
Features:
*Necrosis of fascia - '''key feature'''.<ref name=pmid15735411>{{Cite journal  | last1 = Wong | first1 = CH. | last2 = Wang | first2 = YS. | title = The diagnosis of necrotizing fasciitis. | journal = Curr Opin Infect Dis | volume = 18 | issue = 2 | pages = 101-6 | month = Apr | year = 2005 | doi =  | PMID = 15735411 | URL = http://www.sepeap.org/archivos/pdf/9859.pdf }}</ref>
**[[PMN]]s and necrotic debris (amorphous grey or pink material).
 
Note:
*Fat lobules between septae may be normal.
 
DDx:
*[[Cellulitis]].
 
Images:
*[http://commons.wikimedia.org/wiki/File:Necrotizing_fasciitis_-_intermed_mag.jpg Necrotizing fasciitis - intermed. mag. (WC)].
*[http://commons.wikimedia.org/wiki/File:Necrotizing_fasciitis_-_high_mag.jpg Necrotizing fasciitis - high mag. (WC)].


==Porokeratosis==
==Porokeratosis==
===General===
{{Main|Porokeratosis}}
*Genetic.
*Several subtypes.
 
Notes:
*Not the same as ''punctate porokeratotic keratoderma''.<ref name=pmid20137755>{{Cite journal  | last1 = Alikhan | first1 = A. | last2 = Burns | first2 = T. | last3 = Zargari | first3 = O. | title = Punctate porokeratotic keratoderma. | journal = Dermatol Online J | volume = 16 | issue = 1 | pages = 13 | month =  | year = 2010 | doi =  | PMID = 20137755 | URL = http://dermatology.cdlib.org/1601/case_presentations/ppk/alikhan.html }}</ref>
 
===Microscopic===
Features:
*Cornoid lamella (pathognomonic) - '''key feature''':
**Compact keratosis over a hair follicle.
*+/-Rete ridge loss.
 
Images:
*[[WC]]:
**[http://commons.wikimedia.org/wiki/File:Porokeratosis_-_intermed_mag.jpg Porokeratosis - intermed. mag. (WC)].
**[http://commons.wikimedia.org/wiki/File:Porokeratosis_-_very_high_mag.jpg Porokeratosis - very high mag. (WC)].


==Nevus sebaceous==
==Nevus sebaceous==
*[[AKA]] ''nevus sebaceous of Jadassohn''.
*[[AKA]] ''nevus sebaceous of Jadassohn''.
===General===
{{Main|Nevus sebaceous}}
*Congenital - considered a [[hamartoma]].<ref name=pmid23217958/>
*Usually sporadic - may be transmitted autosomal dominant.<ref name=pmid23217958/>
*Malignant tumours may arise within a ''nevus sebaceous''.
===Gross===
Features:<ref name=pmid23217958>{{Cite journal  | last1 = West | first1 = C. | last2 = Narahari | first2 = S. | last3 = Kwatra | first3 = S. | last4 = Feldman | first4 = S. | title = Autosomal dominant transmission of nevus sebaceous of Jadassohn. | journal = Dermatol Online J | volume = 18 | issue = 11 | pages = 17 | month = Nov | year = 2012 | doi =  | PMID = 23217958 }}</ref><ref name=pmid19171988>{{Cite journal  | last1 = Simi | first1 = CM. | last2 = Rajalakshmi | first2 = T. | last3 = Correa | first3 = M. | title = Clinicopathologic analysis of 21 cases of nevus sebaceus: a retrospective study. | journal = Indian J Dermatol Venereol Leprol | volume = 74 | issue = 6 | pages = 625-7 | month =  | year =  | doi =  | PMID = 19171988 }}</ref>
*Head and neck [[plaque]] or [[papule]] with:
**Well-circumscribed borders.
**Waxy, yellow appearance.
*Area usu. devoid of hair.<ref name=pmid22148058>{{Cite journal  | last1 = Kim | first1 = JH. | last2 = Park | first2 = HY. | last3 = Ahn | first3 = SK. | title = Nevus sebaceous accompanying secondary neoplasms and unique histopathologic findings. | journal = Ann Dermatol | volume = 23 | issue = Suppl 2 | pages = S231-4 | month = Oct | year = 2011 | doi = 10.5021/ad.2011.23.S2.S231 | PMID = 22148058 }}</ref>
 
DDx - gross:
*[[Seborrheic keratosis]].
 
Image:
*[http://www.dermnet.com/images/Nevus-Sebaceous/picture/17082?imgNumber=14 NS (dermnet.com)].
 
===Microscopic===
Features:<ref name=pmid19171988/>
*Abundant sebaceous glands.
*Immature/abortive hair follicles.
**No normal terminal hair follicles.
*Papillomatous epidermal hyperplasia.
 
Images:
*[http://commons.wikimedia.org/wiki/File:SkinTumors-P6260391.JPG NS (WC)].
*[http://www.dermnet.com/images/Nevus-Sebaceous/picture/17087 NS (dermnet.com)].


==Nevus lipomatosus superficialis==
==Nevus lipomatosus superficialis==
Line 1,083: Line 516:
*[[AKA]] ''nevus lipomatosus cutaneous superficialis'', abbreviated ''NLCS''.
*[[AKA]] ''nevus lipomatosus cutaneous superficialis'', abbreviated ''NLCS''.
*[[AKA]] ''nevus lipomatosus''.<ref name=pmid15677959>{{Cite journal  | last1 = Kaw | first1 = P. | last2 = Carlson | first2 = A. | last3 = Meyer | first3 = DR. | title = Nevus lipomatosus (pedunculated lipofibroma) of the eyelid. | journal = Ophthal Plast Reconstr Surg | volume = 21 | issue = 1 | pages = 74-6 | month = Jan | year = 2005 | doi =  | PMID = 15677959 }}</ref>
*[[AKA]] ''nevus lipomatosus''.<ref name=pmid15677959>{{Cite journal  | last1 = Kaw | first1 = P. | last2 = Carlson | first2 = A. | last3 = Meyer | first3 = DR. | title = Nevus lipomatosus (pedunculated lipofibroma) of the eyelid. | journal = Ophthal Plast Reconstr Surg | volume = 21 | issue = 1 | pages = 74-6 | month = Jan | year = 2005 | doi =  | PMID = 15677959 }}</ref>
===General===
{{Main|Nevus lipomatosus superficialis}}
*Rare.
*Congenital - considered a [[hamartoma]].<ref name=pmid22984661/>
*Usually young adults.<ref>URL: [http://www.dermpedia.org/dermpedia-textbook/nevus-lipomatosus http://www.dermpedia.org/dermpedia-textbook/nevus-lipomatosus]. Accessed on: 8 January 2013.</ref>
 
Clinically separated into:<ref name=pmid17288284>{{Cite journal  | last1 = Triki | first1 = S. | last2 = Mekni | first2 = A. | last3 = Haouet | first3 = S. | last4 = Mokni | first4 = M. | last5 = Kchir | first5 = N. | last6 = Ben Osman Dhahri | first6 = A. | last7 = Zitouna | first7 = M. | title = [Nevus lipomatosus cutaneous superficialis: a clinico-pathological study of 13 cases]. | journal = Tunis Med | volume = 84 | issue = 12 | pages = 800-2 | month = Dec | year = 2006 | doi =  | PMID = 17288284 }}</ref>
*''Solitary'' - one lesion.
*''Multiple'' - more than one lesion.
 
===Gross===
Features:<ref name=pmid22984661>{{Cite journal  | last1 = Goucha | first1 = S. | last2 = Khaled | first2 = A. | last3 = Zéglaoui | first3 = F. | last4 = Rammeh | first4 = S. | last5 = Zermani | first5 = R. | last6 = Fazaa | first6 = B. | title = Nevus lipomatosus cutaneous superficialis: Report of eight cases. | journal = Dermatol Ther (Heidelb) | volume = 1 | issue = 2 | pages = 25-30 | month = Dec | year = 2011 | doi = 10.1007/s13555-011-0006-y | PMID = 22984661  | PMC = 3437641 }}</ref>
*Pedunculated lesion.
*Soft.
*Usually lower trunk or gluteal region.<ref name=pmid1235780>{{Cite journal  | last1 = Jones | first1 = EW. | last2 = Marks | first2 = R. | last3 = Pongsehirun | first3 = D. | title = Naevus superficialis lipomatosus. A clinicopathological report of twenty cases. | journal = Br J Dermatol | volume = 93 | issue = 2 | pages = 121-33 | month = Aug | year = 1975 | doi =  | PMID = 1235780 }}</ref>
 
Image:
*[http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3437641/figure/Fig1/ NLS (nih.gov)].<ref name=pmid22984661/>
 
===Microscopic===
Features:<ref name=pmid19495497>{{Cite journal  | last1 = Yap | first1 = FB. | title = Nevus lipomatosus superficialis. | journal = Singapore Med J | volume = 50 | issue = 5 | pages = e161-2 | month = May | year = 2009 | doi =  | PMID = 19495497 | URL = http://smj.sma.org.sg/5005/5005cr3.pdf }}</ref>
*Benign adipose tissue in the dermis.
**Adipocytes in [[reticular dermis]] +/- [[papillary dermis]].<ref name=pmid20673540>{{Cite journal  | last1 = Ghosh | first1 = SK. | last2 = Bandyopadhyay | first2 = D. | last3 = Jamadar | first3 = NS. | title = Nevus lipomatosus cutaneous superficialis: An unusual presentation. | journal = Dermatol Online J | volume = 16 | issue = 7 | pages = 12 | month =  | year = 2010 | doi =  | PMID = 20673540 }}</ref>
 
DDx:
*[[Lipoma]].
*[[Fibroepithelial polyp]] (skin tag).
*[[Intradermal nevus]] with adipocytes.<ref name=pmid9810886>{{Cite journal  | last1 = Eng | first1 = W. | last2 = Cohen | first2 = PR. | title = Nevus with fat: clinical characteristics of 100 nevi containing mature adipose cells. | journal = J Am Acad Dermatol | volume = 39 | issue = 5 Pt 1 | pages = 704-11 | month = Nov | year = 1998 | doi =  | PMID = 9810886 }}</ref>
 
Images:
*[http://www.dermaamin.com/site/images/histo-pic/n/nevus-lipomatosus-superficialis/nevus-lipomatosus-superficialis1.jpg NLS (dermamin.com)].<ref>URL: [http://www.dermaamin.com/site/histopathology-of-the-skin/66-n/1971-nevus-lipomatosus-superficialis----.html http://www.dermaamin.com/site/histopathology-of-the-skin/66-n/1971-nevus-lipomatosus-superficialis----.html]. Accessed on: 7 March 2012.</ref>
*[http://www.humpath.com/IMG/jpg/nevus_superficialis_lipomatosus_01_1.jpg NLS (humpath.com)].<ref>URL: [http://www.humpath.com/spip.php?article8134 http://www.humpath.com/spip.php?article8134]. Accessed on: 17 December 2012.</ref>
*[http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3437641/figure/Fig3/ NLS (nih.gov)].<ref name=pmid22984661/>
*[http://www.dermpedia.org/dermpedia-textbook/nevus-lipomatosus Nevus lipomatosus (dermpedia.org)].
 
===Sign out===
<pre>
SKIN LESION ("SKIN TAG"), LEFT HIP, EXCISION:
- NEVUS LIPOMATOSUS SUPERFICIALIS.
</pre>


=Bullous disease=
=Bullous disease=

Latest revision as of 17:59, 23 April 2024

Non-malignant skin disease is relatively common. The pathology may or may not be specific. Some diseases require clinical information to diagnose.

An introduction to dermatopathology is in the dermatopathology article. Nevi (moles) and other melanocytic lesions are dealt with in the article melanocytic lesions. Inflammatory skin conditions are dealt with in inflammatory skin disorders.

Other

Lichen simplex chronicus

Main article: Lichen simplex chronicus

Prurigo nodularis

  • Abbreviated PN.
  • AKA chronic prurigo and picker nodule.[1]

General

Gross

  • Dome-shaped/raised - papular (<1 cm) or nodular (>1 cm).[2]

Microscopic

DDx:

Sign out

SKIN LESION, LEFT CHIN, BIOPSY: 
- PRURIGO NODULARIS.

Micro

The sections show a raised lesion with compact hyperkeratosis and irregular acanthosis. Spongiosis is seen focally. There is minimal hypergranulosis.

There is no thinning of the suprapapillary plate and no dilated superficial blood vessels. There is no interface activity.

Very common

Dermatomycosis

Dermatophytosis redirects here.

General

Note:

  • Dermatophytosis (ring worm) is a type of dermatomycosis.

Microscopic

Features:

  • Microorganisms - key feature.
    • Often hyphae (candida) - like twigs of a tree... branching.
      • May be very fragmented in section ~ size of a neutrophil.
  • Perivascular inflammation, esp. neutrophils.
  • Exocytosis - blood cell infiltrate the epidermis.

Images

  • Dermatomycosis - intermed. mag. (WC)

  • Dermatomycosis - high mag. (WC)

  • Dermatomycosis - GMS stain - low mag. (WC)

  • Dermatomycosis - GMS stain - high mag. (WC)

www:

Stains

Sign out

SKIN, BIOPSY:
- SKIN WITH SUPERFICIAL FUNGAL ORGANISMS CONSISTENT WITH CANDIDA.
- REACTIVE CHANGES OF THE EPITHELIUM.

Micro

The sections show skin with a neutrophilic infiltrate in the superficial epidermis. PAS-D staining demonstrates fungal organisms with a morphology suggestive of candida.

The epithelium has parakeratosis, acanthosis and spongiosis. No mitotic activity is appreciated. The keratinocytes are moderately enlarged and have evident nucleoli.

Cicatrix

Main article: Dermal scar

Fibroepithelial polyp

Main article: Fibroepithelial polyp

Actinic keratosis

Main article: Actinic keratosis

Actinic cheilitis

General

Microscopic

See actinic keratosis.

Sign out

LESION, LOWER LIP, BIOPSY: 
- ACTINIC CHEILITIS.
- SOLAR ELASTOSIS.

Micro

The sections show skin with moderate basal nuclear hyperchromasia and atypia, and parakeratosis. The squamous epithelium has maturation to the surface. There is no inflammation at the dermal-epidermal interface. Solar elastosis is present.

Seborrheic keratosis

Main article: Seborrheic keratosis

Pilomatricoma

Main article: Pilomatricoma

Dermatofibroma

Main article: Dermatofibroma

Ezcema

General

  • A nebulous thingy.
  • Very common.

DDx:

Microscopic

Features:[5]

  • Spongiosis (epidermal edema); keratinocytes spacing increased - key feature.
  • +/-Interdermal vesicles.
  • +/-Eosinophils (may suggest Rx reaction).
  • Perivascular lymphocytes.

Acne vulgaris

General

  • Extremely common - esp. among adolescents.
  • Very rarely seen by pathologists.

Treatments:

  • Antibiotic (minocycline).
  • Isotretinoin AKA all-trans retinoic acid (ATRA).

Gross

  • Papules, pustules, nodules or cysts.
    • White, black or erythematous.

Images:

Microscopic

Features:[6]

  • Folliculitis:[7]
    • Neutrophils around hair follicle and infiltrate into it - including the follicular canal.
  • Epidermal invagination or cyst at site of a hair follicle - contains:
    • Sebum.
    • +/-Bacteria (Propionibacterium acnes) and inflammatory cells - typically neurophils.

Subtyped into:

  1. Open comedones ("blackheads") - no extension to epidermal surface.
  2. Closed comedones ("whiteheads") - to epidermal surface have wide opening.

DDx - acneiform disorder:[7]

  • Rosacea.
  • Infective folliculitis.
  • Perioral dermatitis.
  • Acne vulgaris.

Image:

Solar elastosis

General

  • Very common.
  • Caused by sun exposure - specifically UV light.[9]
    • Severity correlated with cumulative exposure to UV light..[10]
  • Often co-localized with skin cancers - as UV light is risk factor for skin cancers.[10]
  • Benign.

Microscopic

Features:

  • Grey, spaghetti-like material in the superficial dermis.

DDx:

Note:

  • The DDx above is things associated with sun damaged skin.
  • Dermal mucin (as my be seen in lupus erythematosus) is a possible mimic - but it isn't spaghetti-like and the "background" (an interface dermatitis) is different.

Images

  • Solar elastosis - intermed. mag. (WC)

  • Solar elastosis - high mag. (WC)

www:

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SKIN, RIGHT CHEEK, RE-EXCISION:
- DERMAL SCAR.
- EXTENSIVE SOLAR ELASTOSIS.
Prominent blood vessels
SKIN LESION, LEFT CHEEK, BIOPSY:
- SKIN WITH SOLAR ELASTOSIS AND PROMINENT SMALL BLOOD VESSELS.

SUPERIOR SHOULDER, LEFT, PUNCH BIOPSY:
- BENIGN SKIN WITH MODERATE SOLAR ELASTOSIS, PROMINENT SMALL BLOOD VESSELS AND
  SCATTERED PERIVASCULAR LYMPHOCYTES AND PLASMA CELLS.
- NEGATIVE FOR BASAL CELL CARCINOMA.
- NEGATIVE FOR ACTINIC KERATOSIS.

Micro

The sections show hair bearing skin with solar elastosis and numerous small dilated blood vessels. The dermis is mildly fibrotic. Compact keratin is present.

The epidermis matures to the surface. A granular layer is present. There is no basal epidermal atypia. No melanocytic nests are identified. There is no palisading of the basal cells. Rare scattered lymphocytes are in the dermis.

Very common - viral

Verruca vulgaris

Main article: Verruca vulgaris

Verruca plana

General

  • Common.
  • Usu. hands and face.[11]

Microscopic

Features:[11]

  • Orthokeratosis with basketweave pattern.
  • Hypergranulosis.
  • Viral keratohyaline.
  • Koilocytes.
  • Acanthosis - yet flat surface and base.

Notes:

  • It differs from verruca vulgaris... (1) orthokeratosis, (2) flat surface and base.

Less common

Chronic folliculitis

Folliculitis redirect here.

General

  • Common.
  • Infrequently biopsied.

Gross

DDx gross:

Microscopic

Features:

  • Inflammation around the hair follicle - key feature.
    • Lymphocytes - usu. predominant.
  • +/-Chronic changes:

DDx:

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SKIN LESION, UPPER ARM, BIOPSY:
- CHRONIC FOLLICULITIS WITH SECONDARY SURFACE CHANGES.

Micro

The sections show hair-bearing skin with abundant lymphocytes around and within the hair follicle wall.

The non-hair follicle epidermis has acanthosis, hypergranulosis and compact hyperkeratosis. There is no inflammatory cell infiltrate in the non-hair follicle epidermis or at the non-hair follicle interface.

There are no granulomas.

Clear cell acanthoma

Main article: Clear cell acanthoma

Chondrodermatitis nodularis chronica helicis

  • AKA chondrodermatitis nodularis helicis.
  • Abbreviated CNCH.
  • AKA Winkler disease.[13]
Main article: Chondrodermatitis nodularis chronica helicis

Cutaneous calcinosis

  • AKA calcinosis cutis.
Main article: Cutaneous calcinosis

Dilated pore of Winer

General

  • Benign.
  • Looks like a zit.

Microscopic

Features:[14]

  • Dilated hair follicle with keratin.
  • Acanthosis.
  • Budding of epidermis (into dermis).

DDx:

Image:

Lichenoid keratosis

  • AKA lichen planus-like keratosis.
Main article: Lichenoid keratosis

Granuloma annulare

Main article: Granuloma annulare

Necrobiosis lipoidica

Main article: Necrobiosis lipoidica

Keloid

Main article: Keloid

Angiofibroma

See also: nasopharyngeal angiofibroma.
Should not be confused with angiokeratoma.
Main article: Angiofibroma

Benign fibrous papule

  • AKA fibrous papule.

General

Gross

  • Solitary lesion of the face - important.[15]
    • Usually on the nose.[16]

Microscopic

Features:[17]

  • Dome-shaped.
  • Fibrotic dermis.
    • Enlarged fibroblasts.
  • Dilated small vessels.
  • +/-Multinucleated stromal cells.[18]
  • +/-Stellate cells.[18]

DDx:

Note:

  • Several variants exist.[16]

Images

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SKIN LESION, CHIN, BIOPSY:
- BENIGN FIBROUS PAPULE.

Molluscum contagiosum

Main article: Molluscum contagiosum

Superficial dermal infiltrates

Discussed in detail by Alsaad and Ghazarian.[19]

Dermal perivascular lymphoeosinophilic infiltration

  • Abbreviated DPLI.

Microscopic appearance is just what it is called:

  • Lymphocytes and eosinophils around the vessels in the superficial dermis.

DDx:[19]

Notes:

  • May superficially resemble cutaneous lymphoma.[20]

Images:

Congenital dermal melanocytosis

  • AKA Mongolian spots.
  • Classically seen in asian children.

Gross:

  • Brown or blue-grey patch in the lumbosacral area.

Mastocytosis

Main article: Mastocytosis

Ichthyosis

General

  • Comes in different flavours.
  • Usu. inherited... thus a pediatric condition.

Gross

  • Fish scale-like appearance.

Image:

Microscopic

Features:[21]

  • Thick stratum corneum without basket-weave pattern.

Palmar fibromatosis

  • AKA Dupuytren's contracture.
  • AKA Dupuytren disease.
Main article: Palmar fibromatosis

Angiomyoma

General

  • Benign.
  • Female > male.[22]

Microscopic

Features:

  • Well-circumscribed lesion with fascicular architecture.
  • Spindle cells/epithelioid cell with moderate eosinophilic (pink) cytoplasm.
  • Thick-walled blood vessels. (???)

Images:

Angiokeratoma

Main article: Angiokeratoma

Inverted follicular keratosis

  • Abbreviated IFK.[23]

General

  • Benign skin lesion.
  • Central face - middle age.[24]
  • Uncommon.
  • May be considered a variant of seborrheic keratosis that is predominantly endophytic.[25]

Clinical DDx:[24][26]

Microscopic

Features:[24]

  • Keratinocyte of cytologically benign proliferation.
  • "Squamous eddies" (whorls of keratin).
  • Coarse keratohyaline granules.

DDx:

Images:

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SKIN LESION, FACE, BIOPSY:
- INVERTED FOLLICULAR KERATOSIS.

Micro

The sections show skin with acanthosis, pseudohorn cysts, and focal basal epidermal pigmentation. There is no basal nuclear atypia, no mitoses and there are no melanocytic nests. There is minimal dermal inflammation. There is no apparent solar elastosis.

Focal cutaneous mucinosis

General

  • Benign.
  • May be associated with systemic disease.[27]

Microscopic

Features:

  • Light blue whispy material in the dermis - key feature.

DDx:

Panniculitis

Main article: Panniculitis

This is dealt with in the panniculitis article.

DDx for panniculitis:

Rare

Necrotizing fasciitis

Not to be confused with nodular fasciitis.
  • AKA flesh-eating disease.
Main article: Necrotizing fasciitis

Porokeratosis

Main article: Porokeratosis

Nevus sebaceous

  • AKA nevus sebaceous of Jadassohn.
Main article: Nevus sebaceous

Nevus lipomatosus superficialis

  • Abbreviated NLS.
  • AKA nevus lipomatosus cutaneous superficialis, abbreviated NLCS.
  • AKA nevus lipomatosus.[28]
Main article: Nevus lipomatosus superficialis

Bullous disease

Main article: Bullous disease

Cysts

Main article: Dermal cysts

See also

References

  1. ↑ Busam, Klaus J. (2009). Dermatopathology: A Volume in the Foundations in Diagnostic Pathology Series (1st ed.). Saunders. pp. 26. ISBN 978-0443066542.
  2. ↑ URL: http://www.pediatrics.wisc.edu/education/derm/text.html. Accessed on: 23 August 2012.
  3. ↑ URL: http://missinglink.ucsf.edu/lm/DermatologyGlossary/tinea.html. Accessed on: 25 February 2013.
  4. ↑ Picascia, DD.; Robinson, JK. (Aug 1987). "Actinic cheilitis: a review of the etiology, differential diagnosis, and treatment.". J Am Acad Dermatol 17 (2 Pt 1): 255-64. PMID 3305604.
  5. ↑ Kumar, Vinay; Abbas, Abul K.; Fausto, Nelson; Aster, Jon (2009). Robbins and Cotran pathologic basis of disease (8th ed.). Elsevier Saunders. pp. 1188. ISBN 978-1416031215.
  6. ↑ Busam, Klaus J. (2009). Dermatopathology: A Volume in the Foundations in Diagnostic Pathology Series (1st ed.). Saunders. pp. 76. ISBN 978-0443066542.
  7. ↑ 7.0 7.1 Busam, Klaus J. (2009). Dermatopathology: A Volume in the Foundations in Diagnostic Pathology Series (1st ed.). Saunders. pp. 77. ISBN 978-0443066542.
  8. ↑ URL: http://www.dermnetnz.org/dermal-infiltrative/solar-elastosis.html. Accessed on: 27 March 2013.
  9. ↑ Thomas, NE.; Kricker, A.; From, L.; Busam, K.; Millikan, RC.; Ritchey, ME.; Armstrong, BK.; Lee-Taylor, J. et al. (Nov 2010). "Associations of cumulative sun exposure and phenotypic characteristics with histologic solar elastosis.". Cancer Epidemiol Biomarkers Prev 19 (11): 2932-41. doi:10.1158/1055-9965.EPI-10-0686. PMID 20802019.
  10. ↑ 10.0 10.1 Karagas, MR.; Zens, MS.; Nelson, HH.; Mabuchi, K.; Perry, AE.; Stukel, TA.; Mott, LA.; Andrew, AS. et al. (Mar 2007). "Measures of cumulative exposure from a standardized sun exposure history questionnaire: a comparison with histologic assessment of solar skin damage.". Am J Epidemiol 165 (6): 719-26. doi:10.1093/aje/kwk055. PMID 17204514.
  11. ↑ 11.0 11.1 Humphrey, Peter A; Dehner, Louis P; Pfeifer, John D (2008). The Washington Manual of Surgical Pathology (1st ed.). Lippincott Williams & Wilkins. pp. 480. ISBN 978-0781765275.
  12. ↑ URL: http://www.webmd.com/skin-problems-and-treatments/tc/folliculitis-topic-overview. Accessed on: 7 November 2012.
  13. ↑ URL: http://www.head-face-med.com/content/4/1/2. Accessed on: 16 January 2014.
  14. ↑ Humphrey, Peter A; Dehner, Louis P; Pfeifer, John D (2008). The Washington Manual of Surgical Pathology (1st ed.). Lippincott Williams & Wilkins. pp. 486. ISBN 978-0781765275.
  15. ↑ 15.0 15.1 Busam, Klaus J. (2009). Dermatopathology: A Volume in the Foundations in Diagnostic Pathology Series (1st ed.). Saunders. pp. 505. ISBN 978-0443066542.
  16. ↑ 16.0 16.1 16.2 Jacyk, WK.; Rütten, A.; Requena, L. (2008). "Fibrous papule of the face with granular cells.". Dermatology 216 (1): 56-9. doi:10.1159/000109359. PMID 18032900.
  17. ↑ Humphrey, Peter A; Dehner, Louis P; Pfeifer, John D (2008). The Washington Manual of Surgical Pathology (1st ed.). Lippincott Williams & Wilkins. pp. 492. ISBN 978-0781765275.
  18. ↑ 18.0 18.1 Ragaz, A.; Berezowsky, V. (1979). "Fibrous papule of the face. A study of five cases by electron microscopy.". Am J Dermatopathol 1 (4): 353-6. PMID 543528.
  19. ↑ 19.0 19.1 Alsaad, KO.; Ghazarian, D. (Dec 2005). "My approach to superficial inflammatory dermatoses.". J Clin Pathol 58 (12): 1233-41. doi:10.1136/jcp.2005.027151. PMID 16311340.
  20. ↑ 20.0 20.1 Cotran, Ramzi S.; Kumar, Vinay; Fausto, Nelson; Nelso Fausto; Robbins, Stanley L.; Abbas, Abul K. (2005). Robbins and Cotran pathologic basis of disease (7th ed.). St. Louis, Mo: Elsevier Saunders. pp. 1269. ISBN 0-7216-0187-1.
  21. ↑ Kumar, Vinay; Abbas, Abul K.; Fausto, Nelson; Aster, Jon (2009). Robbins and Cotran pathologic basis of disease (8th ed.). Elsevier Saunders. pp. 1185. ISBN 978-1416031215.
  22. ↑ Katenkamp D, Kosmehl H, Langbein L (1988). "[Angiomyoma. A pathologo-anatomic analysis of 229 cases]" (in German). Zentralbl Allg Pathol 134 (4-5): 423–33. PMID 3201831.
  23. ↑ Shih, CC.; Yu, HS.; Tung, YC.; Tsai, KB.; Cheng, ST. (Jan 2001). "Inverted follicular keratosis.". Kaohsiung J Med Sci 17 (1): 50-4. PMID 11411260.
  24. ↑ 24.0 24.1 24.2 Busam, Klaus J. (2009). Dermatopathology: A Volume in the Foundations in Diagnostic Pathology Series (1st ed.). Saunders. pp. 387. ISBN 978-0443066542.
  25. ↑ Busam, Klaus J. (2009). Dermatopathology: A Volume in the Foundations in Diagnostic Pathology Series (1st ed.). Saunders. pp. 341. ISBN 978-0443066542.
  26. ↑ URL: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC475744/. Accessed on: 11 May 2010.
  27. ↑ Gandhi, V.; Dogra, D.; Pandhi, RK.. "Cutaneous focal mucinosis.". Indian J Dermatol Venereol Leprol 62 (4): 260-1. PMID 20948074.
  28. ↑ Kaw, P.; Carlson, A.; Meyer, DR. (Jan 2005). "Nevus lipomatosus (pedunculated lipofibroma) of the eyelid.". Ophthal Plast Reconstr Surg 21 (1): 74-6. PMID 15677959.
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