Difference between revisions of "Dermatologic neoplasms"

Jump to navigation Jump to search

Dermatologic neoplasms (view source)

Revision as of 04:04, 6 June 2018

29,946 bytes removed ,  04:04, 6 June 2018
→‎Eccrine poroma
 
(131 intermediate revisions by 2 users not shown)
Line 1: Line 1:
This article deals with '''dermatologic neoplasms'''.  It includes '''dermatologic cancer''', which can be deadly.  Collectively, dermatologic cancers are the most common form of cancer.   
This article deals with '''dermatologic neoplasms''', also known as '''skin tumours'''.  It includes '''dermatologic cancer''', which can be deadly.  Collectively, dermatologic cancers are the most common form of cancer.   


An introduction to dermatopathy is found in the ''[[dermatopathology]]'' article.  Non-malignant disease is covered in the ''[[non-malignant skin disease]]'' article.
An introduction to dermatopathy is found in the ''[[dermatopathology]]'' article.  Non-malignant disease is covered in the ''[[non-malignant skin disease]]'' article.
Line 5: Line 5:
=The Big Three malignant=
=The Big Three malignant=
==Basal cell carcinoma==
==Basal cell carcinoma==
*Abbreviated ''BCC''.
{{Main|Basal cell carcinoma}}
===General===
*Very common.
*Sun exposed skin.
*Hair bearing area; tumour derived from hair follicle - a more appropriate name might be ''trichoblastic carcinoma''.<ref name=Ref_Derm389>{{Ref Derm|389}}</ref>
*Very rarely metastasizes:
**Dermatopathologists might see a couple in their career.
**There are only ~ 300 literature reports of metastatic BCC.<ref name=pmid16208438>{{Cite journal  | last1 = Ting | first1 = PT. | last2 = Kasper | first2 = R. | last3 = Arlette | first3 = JP. | title = Metastatic basal cell carcinoma: report of two cases and literature review. | journal = J Cutan Med Surg | volume = 9 | issue = 1 | pages = 10-5 | month = Jan | year = 2005 | doi = 10.1007/s10227-005-0027-1 | PMID = 16208438 }}</ref>
 
====Clinical====
*Telangiectasias.
*Raised pearly nodule.
 
====As part of a syndrome====
*[[Nevoid basal cell carcinoma syndrome]] (NBCCS), AKA ''Gorlin syndrome''.
*[[Bazex syndrome]] (X-linked).<ref>URL: [http://emedicine.medscape.com/article/1101146-diagnosis http://emedicine.medscape.com/article/1101146-diagnosis]. Accessed on: 6 May 2010.</ref>
*[[Xeroderma pigmentosum]].
 
===Microscopic===
Features:<ref name=Ref_PBoD8_1180-1>{{Ref PBoD8|1180-1}}</ref><ref name=Ref_Derm390>{{Ref Derm|390}}</ref>
#Basaloid cells - similar in appearance to basal cells:
#*Moderate blue/grey cytoplasm.
#*Dark ovoid/ellipsoid nucleus with uniform chromatin.
#Palisading of cells at the edge of the cell nests.
#Artefactual separation of cells (forming the nests) from the underlying stroma - '''key feature'''.
#Surrounded by blue [[myxoid stroma|(myxoid) stroma]] - '''key feature'''.
 
May be present:<ref name=Ref_Derm390>{{Ref Derm|390}}</ref>
*[[Dystrophic calcification]].
*[[Amyloid]].
*Inflammation.
 
Notes:
*Palisading = the long axes of the cells are alined and the axes are perpendicular to the interface between the (basaloid cell) nests and stroma.
*Key elements in a list: Artefactual clefting (of nests), Basaloid cells, Peripheral palisading, Myxoid stroma.
**Memory device ''PAM'': palisading, artefactual clefts, myxoid stroma.
 
DDx:
*[[Trichoepithelioma]] - no artefactual cleft.<ref name=Ref_PBoD8_1180-1>{{Ref PBoD8|1180-1}}</ref>
*[[Adenoid cystic carcinoma]] - no myxoid stroma, no peripheral palisading.
*[[Eccrine poroma]] - on palms & soles, BCC rarely found there.<ref>{{Ref DCHH|284}}</ref>
 
Images:
*[[WC]]:
**[http://commons.wikimedia.org/wiki/File:Basal_cell_carcinoma_pathology.jpg BCC - crappy (WC)].
**[http://commons.wikimedia.org/wiki/File:SkinTumors-P6040209.JPG Fibroepithelioma of Pinkus (WC)].
*www:
**[http://missinglink.ucsf.edu/lm/DermatologyGlossary/img/Dermatology%20Glossary/Glossary%20Histo%20Images/basal_cell_carcinoma_high_power.jpg BCC (ucsf.edu)].<ref>URL: [http://missinglink.ucsf.edu/lm/DermatologyGlossary/basal_cell_carcinoma.html http://missinglink.ucsf.edu/lm/DermatologyGlossary/basal_cell_carcinoma.html]. Accessed on: 4 September 2011.</ref>
**[http://www.surgicalpathologyatlas.com/glfusion/mediagallery/media.php?f=1&sort=0&s=20080802171910891 BCC with fibroepitheliomatous pattern / fibroepithelioma of Pinkus (surgicalpathologyatlas.com)].
**[http://dermatlas.med.jhmi.edu/derm/indexDisplay.cfm?ImageID=930934558 BCC with fibroepitheliomatous pattern (dermatlas.med.jhmi.edu)].
 
====Basal cell carcinoma subtypes/unique features====
*Many patterns exist.
*Recurrence higher in morpheaform (sclerosing), infiltrative, micronodular, and superficial patterns.<ref>Basal cell carcinoma. eMedicine. ''Prognosis'' section. URL: [http://emedicine.medscape.com/article/276624-overview http://emedicine.medscape.com/article/276624-overview]. Accessed on: 17 September 2011.</ref>
*DG says the prognosis is similar for all BCC subtypes, except for ''sclerosing'' pattern and ''infiltrative'' pattern.<ref>DG. 14 September 2011.</ref>
 
The subtypes:<ref name=Ref_Derm392-5>{{Ref Derm|392-5}}</ref>
{| class="wikitable sortable" style="margin-left:auto;margin-right:auto"
! Pattern
! Key histologic feature
! Other histologic features
| Other
|-
| Superficial pattern
| connected to epidermis
|
|
|-
| Nodular pattern
| nodules
| partial detachment from epidermis
| subgroup ''micronodular'' = nests equal size ~ 0.2 mm dia., >=25% of lesion
|-
| Morpheaform (sclerosing) pattern
| stroma sclerosis
|
| often seen with ''infiltrative pattern''
|-
| Infiltrative pattern
| small irregular cell aggregates
|
| often also sclerosing or morpheaform
|-
| Fibroepitheliomatous pattern
| cords and columns of basaloid cells
| fibrous stroma
| name of pattern comes from ''fibroepithelioma of Pinkus''
|-
| Infundibulocystic pattern
| small keratocysts (keratin cysts)
| usu. small, often in cords
| usu. indolent
|-
| Adenoidal pattern
| cribriform / pseudoglandular arch.
| myxoid stroma, peripheral palisading
| DDx: [[adenoid cystic carcinoma]]
|-
|}
 
Unique features/differentiation:<ref name=Ref_Derm392-5>{{Ref Derm|392-5}}</ref>
{| class="wikitable sortable" style="margin-left:auto;margin-right:auto"
! Differentiation / unique cell
! Key histologic feature
! Other histologic features
| Other
|-
| Pigmented cells
| '''any pattern''' can have pigmentation
| pigment may be in malignant cell
| DDx: collision lesion with [[melanocytic lesion]]
|-
| Squamous differentiation (metatypical BCC)
| pink cytoplasm, keratinization
|
| assoc. with ulceration/tumour recurrence
|-
| Eccrine differentiation
| focal duct formation
|
| very rare, DDx: BCC engulfing sweat ducts
|-
| Clear cells (Clear cell BCC)
| clear cytoplasm
|
| due to glycogen
|}
 
===IHC===
*CK5/6 +ve.
**Useful to assess [[margins]]... if very close.
*BerEP4 +ve.
**SCC usually negative.<ref name=pmid19187107>{{Cite journal  | last1 = Yu | first1 = L. | last2 = Galan | first2 = A. | last3 = McNiff | first3 = JM. | title = Caveats in BerEP4 staining to differentiate basal and squamous cell carcinoma. | journal = J Cutan Pathol | volume = 36 | issue = 10 | pages = 1074-176 | month = Oct | year = 2009 | doi = 10.1111/j.1600-0560.2008.01223.x | PMID = 19187107 }}</ref>
*CD10 +ve.
*Actin +ve.


==Squamous cell carcinoma of the skin==
==Squamous cell carcinoma of the skin==
{{Main|Squamous carcinoma}}
*Abbreviated ''skin SCC'', ''SCC of the skin'', and ''SCC of skin''.
===General===
{{Main|Squamous cell carcinoma of the skin}}
Precursor:<ref name=Ref_PBoD8_1180>{{Ref PBoD8|1180}}</ref>
*[[Actinic keratosis]] (solar keratosis).
**Clinical: yellow-brown scaly, patches, sandpaper sensation.
 
Risk factors:<ref name=Ref_PBoD8_1180>{{Ref PBoD8|1180}}</ref>
*Sun exposure.
*Immune suppression (e.g. organ transplant recipients).
 
Notes:
*[[Keratoacanthoma]].
**Some don't believe this entity exists.
***These people sign this entity as ''low grade squamous cell carcinoma, keratoacanthoma type''.<ref>RS. 17 May 2010.</ref>
 
===Microscopic===
*See ''[[squamous cell carcinoma]]''.
 
High risk features - for SCC of the skin:<ref>URL: [http://www.cap.org/apps/docs/committees/cancer/cancer_protocols/2011/SkinSquamousCell_11protocol.pdf http://www.cap.org/apps/docs/committees/cancer/cancer_protocols/2011/SkinSquamousCell_11protocol.pdf]. Accessed on: 29 March 2012.</ref>
*Primary site is ear ''or'' lip.†
*Clark level IV/V = reticular dermis or deeper.
*>=2 mm thickness -- measured from stratum granuloma ''or'' ulcer base to deepest aspect.
*[[Lymphovascular invasion]].
*Perineural invasion.
*Poorly differentiated.
 
Note:
* † The words used are "hair-bearing lip" - but there is considerable confusion about this as the AJCC manual contradicts itself.<ref name=pmid21151529>{{Cite journal  | last1 = Buethe | first1 = D. | last2 = Warner | first2 = C. | last3 = Miedler | first3 = J. | last4 = Cockerell | first4 = CJ. | title = Focus Issue on Squamous Cell Carcinoma: Practical Concerns Regarding the 7th Edition AJCC Staging Guidelines. | journal = J Skin Cancer | volume = 2011 | issue =  | pages = 156391 | month =  | year = 2011 | doi = 10.1155/2011/156391 | PMID = 21151529 | PMC = 2990020 | URL = http://www.hindawi.com/journals/jsc/2011/156391/ }}</ref>
 
====Bowen disease====
'''Bowen disease''' is ''[[squamous cell carcinoma]] in situ'' of the skin. 
*Its histomorphologic appearance may be similar to [[Paget disease of the breast]]/[[Extramammary Paget disease]], Toker cell hyperplasia and [[melanoma]]. 
**[[IHC]] is used to separate the entities definitively.
 
Histologic DDx of Bowen disease:
*Benign Toker cell hyperplasia.
*[[Malignant melanoma]].
*[[Paget disease of the breast]].
*[[Eccrine carcinoma]].
 
Images:
*[http://commons.wikimedia.org/wiki/File:Bowen_disease_%281%29.jpg Bowen disease - 1 (WC)].
*[http://commons.wikimedia.org/wiki/File:Bowen_disease_%283%29.jpg Bowen disease - 3 (WC)].
 
===IHC===
Bowen's disease panel:
*CK5/6 +ve.<ref>RS. May 2010.</ref>
**Usu. -ve in [[Paget disease of the breast]]/[[Extramammary Paget disease]].
*S100 -ve, HMB-45 -ve.
**Both typically +ve in melanoma.
*CEA -ve<ref name=emed_pagets>URL: [http://emedicine.medscape.com/article/1101235-workup#a0721 http://emedicine.medscape.com/article/1101235-workup#a0721]. Accessed on: 2 September 2011.</ref> (+ve in [[Paget disease of the breast]]/[[Extramammary Paget disease]], -ve in Toker cells).
*CK7 -ve.
**Toker cells CK7 +ve.<ref name=pmid19601945>{{Cite journal  | last1 = Nofech-Mozes | first1 = S. | last2 = Hanna | first2 = W. | title = Toker cells revisited. | journal = Breast J | volume = 15 | issue = 4 | pages = 394-8 | month =  | year =  | doi = 10.1111/j.1524-4741.2009.00743.x | PMID = 19601945 }}</ref>


==Melanoma==
==Melanoma==
{{Main|Malignant melanoma}}
{{Main|Malignant melanoma}}
===General===
*Known as the great mimicker in pathology; it may look like many things.
*Known as the great mimicker in pathology; it may look like many things.
===Microscopic===
Features:
*Classic appearance of melanoma:
**Loosely cohesive; mix of small nests of cells, single cells.
**Mixed of spindle and ovoid cell morphology.
**+/-Occasional large binucleated cells.
**Cytoplasm: brown pigment (melanin).
**Prominent (large) red nucleoli (like in ''serous carcinoma'' of the ovary).
**Marked nuclear pleomorphism - variation in cell size, shape & staining (like in ''serous carcinoma'' of the ovary).
**[[Nuclear pseudoinclusions]] (like in ''papillary thyroid carcinoma'').


=Less common malignant=
=Less common malignant=
==Dermatofibrosarcoma protuberans==
==Dermatofibrosarcoma protuberans==
*Abbreviated ''DFSP''.
*Abbreviated ''DFSP''.
===General===
{{Main|Dermatofibrosarcoma protuberans}}
*Dermal location.
*Destroys adnexal structures.
*Occasionally transforms to a (more aggressive) [[adult fibrosarcoma|fibrosarcoma]].<ref name=pmid21128251>{{Cite journal  | last1 = Stacchiotti | first1 = S. | last2 = Pedeutour | first2 = F. | last3 = Negri | first3 = T. | last4 = Conca | first4 = E. | last5 = Marrari | first5 = A. | last6 = Palassini | first6 = E. | last7 = Collini | first7 = P. | last8 = Keslair | first8 = F. | last9 = Morosi | first9 = C. | title = Dermatofibrosarcoma protuberans-derived fibrosarcoma: clinical history, biological profile and sensitivity to imatinib. | journal = Int J Cancer | volume = 129 | issue = 7 | pages = 1761-72 | month = Oct | year = 2011 | doi = 10.1002/ijc.25826 | PMID = 21128251 }}</ref>
 
Treatment:<ref name=Ref_PBoD8_1183>{{Ref PBoD8|1183}}</ref>
*Wide excision.
*May include [[imatinib]] (Gleevec).
 
===Gross===
Features:<ref name=Ref_PCPBoD8_600>{{Ref PCPBoD8|600}}</ref>
*Firm plaque, often bosselated, usually on the trunk.
*+/-Ulceration.
 
Images:
*[http://dermatlas.med.jhmi.edu/derm/display.cfm?ImageID=-375107780 Protuberant DFSP (dermatlas.med.jhmi.edu)].
*[http://dermatlas.med.jhmi.edu/derm/indexDisplay.cfm?ImageID=-1421097348 Huge DFSP on back (dermatlas.med.jhmi.edu)].
*[http://dermatlas.med.jhmi.edu/derm/indexDisplay.cfm?ImageID=-109598044 Protuberant DFSP - gross and histology (dermatlas.med.jhmi.edu)].
 
===Microscopic===
Features:<ref name=Ref_PBoD8_1183>{{Ref PBoD8|1183}}</ref>
*Dermal spindle cell lesion with storiform pattern.
**Spokes of the wheel-pattern.
*Contains adipose tissue within the tumour -- '''key feature'''.
**Described as "honeycomb pattern" and "Swiss cheese pattern".
 
Notes:
*Adnexal structure within tumour are preserved -- this is unusual for a malignant tumour -- '''important'''.
 
 
Main DDx:
*[[Dermatofibroma]] - has entrapment of collagen bundles at the edge of the lesion.
 
DDx of storiform pattern:
*DFSP, dermatofibroma, [[solitary fibrous tumour]], [[undifferentiated pleomorphic sarcoma]].
 
Images:
*[http://commons.wikimedia.org/w/index.php?title=File:Storiform_pattern_-_intermed_mag.jpg DFSP - storiform pattern - intermed. mag. (WC)].
*[http://commons.wikimedia.org/wiki/File:Storiform_pattern_-_very_high_mag.jpg DFSP - storiform pattern - very high mag. (WC)].
*[http://webpathology.com/image.asp?case=317&n=1 DFSP (webpathology.com)].
 
===IHC===
Panel:<ref>AP. May 2009.</ref>
*CD34 +ve.
**Usually negative in dermatofibroma.<ref name=pmid7694515>{{cite journal |author=Abenoza P, Lillemoe T |title=CD34 and factor XIIIa in the differential diagnosis of dermatofibroma and dermatofibrosarcoma protuberans |journal=Am J Dermatopathol |volume=15 |issue=5 |pages=429–34 |year=1993 |month=October |pmid=7694515 |doi= |url=}}</ref><ref name=pmid9129699>{{cite journal |author=Goldblum JR, Tuthill RJ |title=CD34 and factor-XIIIa immunoreactivity in dermatofibrosarcoma protuberans and dermatofibroma |journal=Am J Dermatopathol |volume=19 |issue=2 |pages=147–53 |year=1997 |month=April |pmid=9129699 |doi= |url=}}</ref>
*Factor XIIIa -ve.
**Usually positive in dermatofibroma.<ref name=pmid7694515>{{cite journal |author=Abenoza P, Lillemoe T |title=CD34 and factor XIIIa in the differential diagnosis of dermatofibroma and dermatofibrosarcoma protuberans |journal=Am J Dermatopathol |volume=15 |issue=5 |pages=429–34 |year=1993 |month=October |pmid=7694515 |doi= |url=}}</ref><ref name=pmid9129699>{{cite journal |author=Goldblum JR, Tuthill RJ |title=CD34 and factor-XIIIa immunoreactivity in dermatofibrosarcoma protuberans and dermatofibroma |journal=Am J Dermatopathol |volume=19 |issue=2 |pages=147–53 |year=1997 |month=April |pmid=9129699 |doi= |url=}}</ref>
*S100 -ve (screen for melanoma).
*Caldesmin -ve (screen for muscle differentiation).
*Beta-catenin. (???)
*MIB1 (proliferation marker).
**Should not be confused with ''MIB-1'' a gene that regulates [[apoptosis]].
 
===Molecular===
A characteristic [[translocation]] is seen:<ref>{{Ref PBoD8|1249}}</ref>
t(17;22)(q22;q15) COLA1/PDGFB.


==Cutaneous B-cell lymphoma==
==Cutaneous B-cell lymphoma==
Line 288: Line 36:
==Cutaneous T-cell lymphoma==
==Cutaneous T-cell lymphoma==
*Abbreviated CTCL.
*Abbreviated CTCL.
{{Main|Cutaneous T-cell lymphoma}}


==Merkel cell carcinoma==
{{Main|Merkel cell carcinoma}}
==Eccrine carcinoma==
===General===
===General===
*''Mycosis fungoides'' - is a subtype (???).
*Arises from the proximal sweat duct.
*CTCL is more common than cutaneous B-cell lymphoma (CBCL).<ref>URL: [http://emedicine.medscape.com/article/1099540-overview http://emedicine.medscape.com/article/1099540-overview]. Accessed on: 24 August 2010.</ref><ref>URL: [http://emedicine.medscape.com/article/1098342-overview http://emedicine.medscape.com/article/1098342-overview]. Accessed on: 24 August 2010.</ref>


Stages - like [[Kaposi sarcoma]]:
===Microscopic===
*Patch.
Features:
*Plaque.
*Pleomorphic nuclei with nucleoli.
*Nodular.
*Duct-like structures - '''key feature'''.
*Extends from dermis into epidermis (follows path of a benign sweat duct).


===Microscopic===
Notes:
*Atypical lymphocytes:
*May resemble [[Extramammary Paget's disease]]/[[Paget's disease of the breast]].
**Have folded "cerebriform" nuclei; ''Sezary-Lutzner cells''.<ref name=Ref_Klatt385>{{Ref Klatt|385}}</ref>
*Grouping:
**Nests in the epidermis - known as "Pautrier microabscesses".
**Single lymphocytes in epidermis; "lymphocyte exocytosis".<ref>URL: [http://www.mdconsult.com/das/book/body/199872830-2/0/1709/I4-u1.0-B978-0-443-06694-8..50117-2--f2.fig http://www.mdconsult.com/das/book/body/199872830-2/0/1709/I4-u1.0-B978-0-443-06694-8..50117-2--f2.fig]. Accessed on: 6 May 2010.</ref>
**Short linear arrays of lymphocytes along the basal layer of the epidermis; "epidermotropism".<ref name=Ref_Klatt385>{{Ref Klatt|385}}</ref>


DDx:
==Kaposi sarcoma==
*[[Lymphomatoid papulosis]].
:See ''[[Kaposi sarcoma]]''.


Images:
==Sebaceous carcinoma==
*[http://commons.wikimedia.org/wiki/File:Cutaneous_T-cell_lymphoma_-_very_high_mag.jpg CTCL - very high mag. (WC)].
{{Main|Sebaceous carcinoma}}
*[http://commons.wikimedia.org/wiki/File:Cutaneous_T-cell_lymphoma_-_intermed_mag.jpg CTCL - intermed. mag. (WC)].
*[http://www.jci.org/articles/view/24826/figure/2 CTCL (jci.org)].
*[http://www.mdconsult.com/das/book/body/199872830-2/0/1709/I4-u1.0-B978-0-443-06694-8..50117-2--f2.fig CTCL (mdconsult.com)].


===IHC===
==Microcystic adnexal carcinoma==
Key stain:
{{Main|Microcystic adnexal carcinoma}}
*CD4 +ve.<ref>{{Ref PBoD8|1185}}</ref>


Other stains:
==Trichilemmal carcinoma==
*CD3 +ve.
{{Main|Trichilemmal carcinoma}}
*CD8 -ve.
*CD20 -ve (to r/o significant B cell population).
*CD30 -ve.
*CD5 +ve.
*CD7 -ve (often lost first in T cell lymphomas).
*Ki-67 high.
*CD56 -ve.


==Lymphomatoid papulosis==
==Lymphomatoid papulosis==
Line 347: Line 84:
*CD30 +ve.<ref>URL: [http://path.upmc.edu/cases/case513/dx.html http://path.upmc.edu/cases/case513/dx.html]. Accessed on: 25 January 2012.</ref>
*CD30 +ve.<ref>URL: [http://path.upmc.edu/cases/case513/dx.html http://path.upmc.edu/cases/case513/dx.html]. Accessed on: 25 January 2012.</ref>


==Merkel cell carcinoma==
=Rare malignant=
*Abbreviated ''MCC''.
==Basosquamous carcinoma==
 
:Should '''not''' be confused with ''basaloid [[squamous cell carcinoma]]'' ([[AKA]] ''squamous cell carcinoma, basaloid variant'').
===General===
===General===
Features:<ref name=pmid20418670>{{Cite journal  | last1 = Calder | first1 = KB. | last2 = Smoller | first2 = BR. | title = New insights into merkel cell carcinoma. | journal = Adv Anat Pathol | volume = 17 | issue = 3 | pages = 155-61 | month = May | year = 2010 | doi = 10.1097/PAP.0b013e3181d97836 | PMID = 20418670 }}</ref>
*Very rare.
*Rare.
**Largest case series, as of 2000, 35 cases.<ref name=pmid10717618>{{Cite journal  | last1 = Martin | first1 = RC. | last2 = Edwards | first2 = MJ. | last3 = Cawte | first3 = TG. | last4 = Sewell | first4 = CL. | last5 = McMasters | first5 = KM. | title = Basosquamous carcinoma: analysis of prognostic factors influencing recurrence. | journal = Cancer | volume = 88 | issue = 6 | pages = 1365-9 | month = Mar | year = 2000 | doi = | PMID = 10717618 }}
*Aggressive course/poor prognosis.
*Neuroendocrine-like.<ref name=pmid19395876>{{Cite journal  | last1 = Pulitzer | first1 = MP. | last2 = Amin | first2 = BD. | last3 = Busam | first3 = KJ. | title = Merkel cell carcinoma: review. | journal = Adv Anat Pathol | volume = 16 | issue = 3 | pages = 135-44 | month = May | year = 2009 | doi = 10.1097/PAP.0b013e3181a12f5a | PMID = 19395876 }}
</ref>
</ref>
 
*May be considered an aggressive variant of [[basal cell carcinoma]].<ref name=pmid10717618/>
Etiology:
*Aggressive behaviour.<ref name=pmid12859383>{{Cite journal  | last1 = Bowman | first1 = PH. | last2 = Ratz | first2 = JL. | last3 = Knoepp | first3 = TG. | last4 = Barnes | first4 = CJ. | last5 = Finley | first5 = EM. | title = Basosquamous carcinoma. | journal = Dermatol Surg | volume = 29 | issue = 8 | pages = 830-2; discussion 833 | month = Aug | year = 2003 | doi =  | PMID = 12859383 }}.</ref>
*Most caused by ''Merkel cell [[polyomavirus]]''.<ref name=pmid18202256>{{Cite journal  | last1 = Feng | first1 = H. | last2 = Shuda | first2 = M. | last3 = Chang | first3 = Y. | last4 = Moore | first4 = PS. | title = Clonal integration of a polyomavirus in human Merkel cell carcinoma. | journal = Science | volume = 319 | issue = 5866 | pages = 1096-100 | month = Feb | year = 2008 | doi = 10.1126/science.1152586 | PMID = 18202256 }}</ref><ref name=pmid20418670/>
*Immunocompromised/immunosuppressed (e.g. organ transplant recipients).
 
===Microscopic===
Features:<ref name=Ref_WMSP491>{{Ref WMSP|491}}</ref>
*Neuroendocrine nuclear features - round nucleus, small nucleoli/no nucleolus, stippled chromatin - '''key feature'''.
*Typically medium size cells ~3x resting lymphocyte.
**May be small or large.
*Architecture: nests, sheets or trabeculae.
*Scant cytoplasm.
*Abundant mitoses. †
*+/-Nuclear moulding.
**Nuclei of adjacent cells conform to one another.
*+/-Tumour infiltrating lymphocytes. ‡ 
 
Notes:
*† >10 mitoses/HPF = poor prognosis - definition suffers from [[HPFitis]].<ref name=capp_mcc>URL: [http://www.cap.org/apps/docs/committees/cancer/cancer_protocols /2011/SkinMerkelCell_11protocol.pdf http://www.cap.org/apps/docs/committees/cancer/cancer_protocols/2011/SkinMerkelCell_11protocol.pdf]. Accessed on: 28 March 2012.</ref>
*‡ May be associated with a worse prognosis.<ref name=capp_mcc/>
*Merkel cell carcinoma [[lymph node metastases]] is difficult to diagnose with routine stains; use of IHC stains are advised.<ref name=capp_mcc/>
 
DDx:
*[[Basal cell carcinoma]] - no stippled chromatin, less mitoses active.
*Cutaneous [[Ewing sarcoma]] - sorted-out with immunostains.
*[[Lymphoma]].
**[[Burkitt lymphoma]].
*Metastatic small cell carcinoma.
*Other [[small round cell tumours]].
 
Images:
*www:
**[http://www.bccancer.bc.ca/HPI/CE/cytotechnology/cytosleuthquiz/nongyne/ng12hist.htm MCC (bccancer.bc.ca)].
**[http://www.joplink.net/prev/200403/07.html MCC (joplink.net)].
**[http://www.ispub.com/ispub/ijd/volume_5_number_2_8/concurrent_merkel_cell_carcinoma_and_bowen_s_disease_of_the_thigh/bowen-fig3.jpg Merkel cell carcinoma (ispub.com)].
**[http://path.upmc.edu/cases/case398.html Merkel cell carcinoma - several images (upmc.edu)].
*[[WC]]:
**[http://commons.wikimedia.org/wiki/File:Merkel_cell_carcinoma_-_intermed_mag.jpg MCC - intermed. mag. (WC)].
**[http://commons.wikimedia.org/wiki/File:Merkel_cell_carcinoma_-_very_high_mag.jpg MCC - very high mag. (WC)].
**[http://commons.wikimedia.org/wiki/File:Merkelcellcarcinoma_Tag.jpg Merkel cell carcinoma - nested pattern (WC)].
 
===IHC===
Features:
*CK7 -ve.
*CK20 +ve (perinuclear dot-like).<ref name=pmid11533085>{{Cite journal  | last1 = Leech | first1 = SN. | last2 = Kolar | first2 = AJ. | last3 = Barrett | first3 = PD. | last4 = Sinclair | first4 = SA. | last5 = Leonard | first5 = N. | title = Merkel cell carcinoma can be distinguished from metastatic small cell carcinoma using antibodies to cytokeratin 20 and thyroid transcription factor 1. | journal = J Clin Pathol | volume = 54 | issue = 9 | pages = 727-9 | month = Sep | year = 2001 | doi =  | PMID = 11533085 | URL = http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1731517/  }}</ref>
*CAM5.2 +ve (dot-like pattern).
*CD56 +ve.
*AE1/AE3 +ve.
*Merkel cell polyomavirus +ve ~85% of cases.<ref name=pmid21870327>{{Cite journal  | last1 = Jung | first1 = HS. | last2 = Choi | first2 = YL. | last3 = Choi | first3 = JS. | last4 = Roh | first4 = JH. | last5 = Pyon | first5 = JK. | last6 = Woo | first6 = KJ. | last7 = Lee | first7 = EH. | last8 = Jang | first8 = KT. | last9 = Han | first9 = J. | title = Detection of Merkel cell polyomavirus in Merkel cell carcinomas and small cell carcinomas by PCR and immunohistochemistry. | journal = Histol Histopathol | volume = 26 | issue = 10 | pages = 1231-41 | month = Oct | year = 2011 | doi =  | PMID = 21870327 }}</ref>
 
Others:
*TTF-1 -ve.
 
===EM===
*''[[Neurosecretory granules]]'' ([[AKA]] dense-core granules).<ref name=pmid9062165>{{Cite journal  | last1 = Gil-Moreno | first1 = A. | last2 = Garcia-Jiménez | first2 = A. | last3 = González-Bosquet | first3 = J. | last4 = Esteller | first4 = M. | last5 = Castellví-Vives | first5 = J. | last6 = Martínez Palones | first6 = JM. | last7 = Xercavins | first7 = J. | title = Merkel cell carcinoma of the vulva. | journal = Gynecol Oncol | volume = 64 | issue = 3 | pages = 526-32 | month = Mar | year = 1997 | doi =  | PMID = 9062165 }}</ref>
 
==Eccrine carcinoma==
===General===
*Arises from the proximal sweat duct.


===Microscopic===
===Microscopic===
Features:
Features:
*Pleomorphic nuclei with nucleoli.
*Has features of both [[basal cell carcinoma]] and [[squamous cell carcinoma of the skin|squamous cell carcinoma]].<ref name=pmid12859383/>
*Duct-like structures - '''key feature'''.
**BCC component usually predominant.<ref name=Ref_Derm397>{{Ref Derm|397}}</ref>
*Extends from dermis into epidermis (follows path of a benign sweat duct).


Notes:
Note:
*May resemble [[Extramammary Paget's disease]]/[[Paget's disease of the breast]].
*''Busam'' notes that there is disagreement about what defines this tumour;<ref name=Ref_Derm372>{{Ref Derm|372}}</ref> however, he goes on the describe it as a ''[[collision tumour]]''.<ref name=Ref_Derm397>{{Ref Derm|397}}</ref>
 
==Kaposi sarcoma==
:See ''[[Kaposi sarcoma]]''.
 
==Sebaceous carcinoma==
===General===
*Malignant.
*May arise in a [[salivary gland]].<ref name=Warman/>
 
Notes:
*Sebaceous lesions (from benign to malignant): [[sebaceous hyperplasia]], [[sebaceous adenoma]], sebaceoma, sebaceous carcinoma.
 
===Microscopic===
Features:
*Nuclear atypia.
*Sebaceous differentiation:
**Abundant pale fluffy cytoplasm.
 
Images:
*www:
**[http://www.ispub.com/journal/the-internet-journal-of-otorhinolaryngology/volume-9-number-2/sebaceous-adenocarcinoma-of-the-parotid-gland-a-case-report-and-literature-review.article-g01.fs.jpg Sebaceous carcinoma (ispub.com)].<ref name=Warman>URL: [http://www.ispub.com/journal/the_internet_journal_of_otorhinolaryngology/volume_9_number_2_11/article/sebaceous_adenocarcinoma_of_the_parotid_gland_a_case_report_and_literature_review.html http://www.ispub.com/journal/the_internet_journal_of_otorhinolaryngology/volume_9_number_2_11/article/sebaceous_adenocarcinoma_of_the_parotid_gland_a_case_report_and_literature_review.html]. Accessed on: 8 September 2011.</ref>
*[[WC]]:
**[http://commons.wikimedia.org/wiki/File:Sebaceous_carcinoma_-_intermed_mag.jpg Sebaceous carcinoma - intermed. mag. (WC)].
**[http://commons.wikimedia.org/wiki/File:Sebaceous_carcinoma_-_very_high_mag.jpg Sebaceous carcinoma - very high mag. (WC)].
 
===IHC===
*CK7 +ve.<ref name=pmid21592202>{{Cite journal  | last1 = Ansai | first1 = S. | last2 = Arase | first2 = S. | last3 = Kawana | first3 = S. | last4 = Kimura | first4 = T. | title = Immunohistochemical findings of sebaceous carcinoma and sebaceoma: retrieval of cytokeratin expression by a panel of anti-cytokeratin monoclonal antibodies. | journal = J Dermatol | volume = 38 | issue = 10 | pages = 951-8 | month = Oct | year = 2011 | doi = 10.1111/j.1346-8138.2011.01274.x | PMID = 21592202 }}</ref>
 
==Microcystic adnexal carcinoma==
*[[AKA]] ''syringomatous carcinoma'', [[AKA]] ''sclerosing sweat duct carcinoma''.<ref name=dermaamin>URL: [http://www.dermaamin.com/site/histopathology-of-the-skin/65-m/1926-microcystic-adnexal-carcinoma-.html http://www.dermaamin.com/site/histopathology-of-the-skin/65-m/1926-microcystic-adnexal-carcinoma-.html]. Accessed on: 16 September 2011.</ref>
===General===
*Low-grade tumour.
*Adults.
 
===Microscopic===
Features:<ref>{{Ref Derm|412}}</ref>
*Small basaloid cells - often forming small cystic spaces - '''key feature'''.
*Fibrotic stroma.


DDx:
DDx:
*Sclerosing [[basal cell carcinoma]].
*Basaloid [[squamous cell carcinoma]].
*Desmoplastic [[trichoepithelioma]].
*[[Basal cell carcinoma]] with squamous differentiation.
*Infiltrative [[squamous cell carcinoma]].
 
Image:
*[http://www.dermaamin.com/site/images/histo-pic/m/microcystic-adnexal-carcinoma/microcystic-adnexal-carcinoma2.jpg Microcystic adnexal carcinoma (dermaamin.com)].<ref name=dermaamin>URL: [http://www.dermaamin.com/site/histopathology-of-the-skin/65-m/1926-microcystic-adnexal-carcinoma-.html http://www.dermaamin.com/site/histopathology-of-the-skin/65-m/1926-microcystic-adnexal-carcinoma-.html]. Accessed on: 16 September 2011.</ref>
 
==Trichilemmal carcinoma==
===General===
*Super rare.
*Not well-described.
 
===Microscopic===
Features:<ref>{{Ref Derm|399-400}}</ref>
*Clear (glycogen-rich) cytoplasm in center of lesion.
*Peripheral palisading at edge of lesion - root sheath differentiation (hair follicle).
*Contiguous with hair follicle ''or'' assoc. with [[trichilemmoma]].
 
DDx:
*[[Squamous cell carcinoma]], clear cell variant.
*[[Basal cell carcinoma]], clear cell variant.
*[[Trichilemmoma]].


=Intermediate=
=Intermediate=
==Atypical fibroxanthoma==
==Atypical fibroxanthoma==
*Abbreviated ''AFX''.
*Abbreviated ''AFX''.
===General===
{{Main|Atypical fibroxanthoma}}
*Typically head & neck region.<ref>URL: [http://emedicine.medscape.com/article/1056204-overview http://emedicine.medscape.com/article/1056204-overview]. Accessed on 2 September 2011.</ref>
*Thought to be related to [[pleomorphic undifferentiated sarcoma]];<ref>{{Cite journal  | last1 = Withers | first1 = AH. | last2 = Brougham | first2 = ND. | last3 = Barber | first3 = RM. | last4 = Tan | first4 = ST. | title = Atypical fibroxanthoma and malignant fibrous histiocytoma. | journal = J Plast Reconstr Aesthet Surg | volume =  | issue =  | pages =  | month = Jun | year = 2011 | doi = 10.1016/j.bjps.2011.05.004 | PMID = 21664889 }}</ref> some say it is the same thing.<ref name=danny>DG. 16 September 2011.</ref>
 
Clinical:
*Rapid growth.
*Elderly.
*Good prognosis.<ref name=pmid20526171>{{Cite journal  | last1 = Beer | first1 = TW. | last2 = Drury | first2 = P. | last3 = Heenan | first3 = PJ. | title = Atypical fibroxanthoma: a histological and immunohistochemical review of 171 cases. | journal = Am J Dermatopathol | volume = 32 | issue = 6 | pages = 533-40 | month = Aug | year = 2010 | doi = 10.1097/DAD.0b013e3181c80b97 | PMID = 20526171 }}</ref>
 
===Microscopic===
Features:<ref name=Ref_Derm521>{{Ref Derm|521}}</ref>
*Dermal lesion - '''key point'''.
*Marked nuclear atypia.
*Mitoses.
*Mulitnucleated cells.
*Foamy cytoplasm - '''key feature'''.
 
DDx:
*[[Melanoma]].
*[[Pleomorphic undifferentiated sarcoma]] (MFH).
*[[Leiomyosarcoma]].
*Sarcomatoid [[squamous carcinoma]].
 
Notes:
*No Grenz zone. (???)
 
Image:
*[http://dermatology.cdlib.org/141/case_reports/afx/1.jpg AFX (cdlib.org)].<ref name=pmid18319023>{{Cite journal  | last1 = Vandergriff | first1 = TW. | last2 = Reed | first2 = JA. | last3 = Orengo | first3 = IF. | title = An unusual presentation of atypical fibroxanthoma. | journal = Dermatol Online J | volume = 14 | issue = 1 | pages = 6 | month =  | year = 2008 | doi =  | PMID = 18319023 }}</ref>
 
===IHC===
Features:<ref name=Ref_Derm521>{{Ref Derm|521}}</ref>
*S100 -ve (done to r/o melanoma).
*34betaE12 -ve, p63 -ve (done to exclude SCC).
*Desmin -ve (done to r/o leiomyosarcoma).


=Benign=
=Benign=
Line 530: Line 116:
*Benign sweat duct tumour.
*Benign sweat duct tumour.
*Eccrine differentiation.
*Eccrine differentiation.
*Usually close to lower eyelid.<ref>{{Ref PBoD8|1177}}</ref>
*Usually close to lower [[eyelid]].<ref>{{Ref PBoD8|1177}}</ref>


===Microscopic===
===Microscopic===
Line 563: Line 149:


Images:
Images:
*[http://www.ispub.com/ispub/ijd/volume_7_number_1_18/cutaneous_mixed_tumor/mixed-fig1.jpg Chondroid syringoma - low mag. (ispub.com)].<ref name=ispub_mts>URL: [http://www.ispub.com/journal/the_internet_journal_of_dermatology/volume_7_number_2_23/article/cutaneous_mixed_tumor.html http://www.ispub.com/journal/the_internet_journal_of_dermatology/volume_7_number_2_23/article/cutaneous_mixed_tumor.html]. Access on: 21 September 2011.</ref>
*[https://www.dermnetnz.org/topics/apocrine-mixed-tumour-pathology Chondroid syringoma (DermnetNZ)].
*[http://www.ispub.com/ispub/ijd/volume_7_number_1_18/cutaneous_mixed_tumor/mixed-fig2.jpg Chondroid syringoma - high mag. (ispub.com)].<ref name=ispub_mts>URL: [http://www.ispub.com/journal/the_internet_journal_of_dermatology/volume_7_number_2_23/article/cutaneous_mixed_tumor.html http://www.ispub.com/journal/the_internet_journal_of_dermatology/volume_7_number_2_23/article/cutaneous_mixed_tumor.html]. Access on: 21 September 2011.</ref>


==Dermal cylindroma==
==Dermal cylindroma==
===General===
{{Main|Dermal cylindroma}}
*Benign skin lesion.
**Occasionally malignant.<ref name=pmid16882695/>
*Should not be confused with ''cylindroma'' ([[adenoid cystic carcinoma]]).
*May be related to ''[[eccrine spiradenoma]]''.<ref name=pmid6302142>{{Cite journal  | last1 = Gerber | first1 = JE. | last2 = Descalzi | first2 = ME. | title = Eccrine spiradenoma and dermal cylindroma. | journal = J Cutan Pathol | volume = 10 | issue = 1 | pages = 73-8 | month = Feb | year = 1983 | doi =  | PMID = 6302142 }}</ref><ref name=pmid8936072>{{Cite journal  | last1 = Lee | first1 = MW. | last2 = Kelly | first2 = JW. | title = Dermal cylindroma and eccrine spiradenoma. | journal = Australas J Dermatol | volume = 37 | issue = 1 | pages = 48-9 | month = Feb | year = 1996 | doi =  | PMID = 8936072 }}</ref>
 
May be familial:<ref name=pmid16882695/>
*Familial cylindromatosis (autosomal dominant).
*Brook–Spiegler syndrome.
 
===Gross===
*Classically scalp - usually head and neck or face.
 
===Microscopic===
Features:<ref name=pmid16882695/>
*Nests of cells that fit together like a jigsaw puzzle - the borders of the nests are opposed and undulate.
*#Basaloid cells with scant cytoplasm and dark nuclei palisade around the edge of the nests.
*#Larger cells with moderate eosinophilic cytoplasm and lighter staining nuclei are at the centre of the nests.
*Cells nests surrounded by a band of hyaline (i.e. glassy, eosinophilic, acellular) material ~ 2X thickness of a basilar cell - '''key feature'''.
**This is basement membrane.
DDx:
*[[Eccrine spiradenoma]].
*[[Basal cell carcinoma]] - has [[myxoid stroma]].
 
Images:
*[[WC]]:
**[http://commons.wikimedia.org/wiki/File:Dermal_cylindroma_intermed_mag.jpg Dermal cylindroma (WC)].
**[http://commons.wikimedia.org/wiki/File:Dermal_cylindroma_intermed_mag_deep.jpg Dermal cylindroma - high mag. (WC)].
*www:
**[http://jcp.bmj.com/content/60/2/145/F7.large.jpg Dermal cylindroma (bmj.com)].<ref name=pmid16882695>{{Cite journal  | last1 = Obaidat | first1 = NA. | last2 = Alsaad | first2 = KO. | last3 = Ghazarian | first3 = D. | title = Skin adnexal neoplasms--part 2: an approach to tumours of cutaneous sweat glands. | journal = J Clin Pathol | volume = 60 | issue = 2 | pages = 145-59 | month = Feb | year = 2007 | doi = 10.1136/jcp.2006.041608 | PMID = 16882695 | PMC = 1860616 | URL = http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1860616/?tool=pubmed }}</ref>
 
===Stains===
*PAS +ve (basement membrane).<ref name=pmid16882695/>


==Keratoacanthoma==
==Keratoacanthoma==
*Abbreviated ''KA''.
{{Main|Keratoacanthoma}}
===General===
*Generally considered to be benign.
**Rare reports of [[metastases]] suggesting it may be a form of [[squamous cell carcinoma]].<ref>{{cite journal |author=Mandrell JC, Santa Cruz D |title=Keratoacanthoma: hyperplasia, benign neoplasm, or a type of squamous cell carcinoma? |journal=Semin Diagn Pathol |volume=26 |issue=3 |pages=150–63 |year=2009 |month=August |pmid=20043514 |doi= |url=}}</ref>
 
====Clinical====
*May grow rapidly (weeks or months) then involute.
*Main DDx is [[squamous cell carcinoma]].
*Exophytic lesion, well-circumscribed.
 
===Microscopic===
Features:<ref name=Ref_Klatt378>{{Ref Klatt|378}}</ref>
*Expansion of stratum spinosum - pushing [[tongue]]-like downward growth of epidermis into the dermis.
*Keratin collection ("keratin plug") at the center of lesion-superficial aspect.
*Cells have glassy pink cytoplasm.
*Minimal/no nuclear atypia.
 
Note:
*Classically described as a "volcano lesion" with pale pink cells.
*May have features of regression - [[PMN]]s, fibrosis (???).
 
Image:
*[http://commons.wikimedia.org/wiki/File:Skin_keratoacanthoma_whole_slide.jpg Keratocanthoma (WC).]


==Sebaceous adenoma==
==Sebaceous adenoma==
Line 640: Line 170:
**Multiple dilated glands - opening to the surface.
**Multiple dilated glands - opening to the surface.


Images:
====Images====
*www:
<gallery>
**[http://dermatlas.med.jhmi.edu/derm/indexDisplay.cfm?ImageID=587283984 Sebaceous adenoma (jhmi.edu)].
Image:Sebaceous_adenoma_-_low_mag.jpg | Sebaceous adenoma - low mag. (WC/Nephron)
*[[WC]]:
Image:Sebaceous_adenoma_-_high_mag.jpg | Sebaceous adenoma - high mag. (WC/Nephron)
**[http://commons.wikimedia.org/wiki/File:Sebaceous_adenoma_-_low_mag.jpg Sebaceous adenoma - low mag. (WC)].
</gallery>
**[http://commons.wikimedia.org/wiki/File:Sebaceous_adenoma_-_high_mag.jpg Sebaceous adenoma - high mag. (WC)].
www:
*[http://dermatlas.med.jhmi.edu/derm/indexDisplay.cfm?ImageID=587283984 Sebaceous adenoma (jhmi.edu)].


==Trichilemmoma==
==Trichilemmoma==
*May be spelled ''tricholemmoma''.
*May be spelled ''tricholemmoma''.
===General===
{{Main|Trichilemmoma}}
*Benign neoplasm with features of the pilosebaceous follicular epithelium.<ref>URL: [http://emedicine.medscape.com/article/1059940-overview http://emedicine.medscape.com/article/1059940-overview]. Accessed on: 2 September 2011.</ref>
 
*Associated with ''nevus sebaceous''.<ref name=pmid16503928>{{Cite journal  | last1 = Baykal | first1 = C. | last2 = Buyukbabani | first2 = N. | last3 = Yazganoglu | first3 = KD. | last4 = Saglik | first4 = E. | title = [Tumors associated with nevus sebaceous]. | journal = J Dtsch Dermatol Ges | volume = 4 | issue = 1 | pages = 28-31 | month = Jan | year = 2006 | doi = 10.1111/j.1610-0387.2006.05855.x | PMID = 16503928 }}</ref>
==Poroma==
*Muliple trichilemmomas associated with [[Cowden syndrome]].<ref name=Ref_Derm386>{{Ref Derm|386}}</ref>
{{Main|Poroma}}


===Microscopic===
==Nodular hidradenoma==
Features:<ref name=Ref_Derm386>{{Ref Derm|386}}</ref>
*[[AKA]] ''eccrine acrospiroma''.<ref name=pmid18319032>{{Cite journal  | last1 = Punia | first1 = RP. | last2 = Garg | first2 = S. | last3 = Bal | first3 = A. | last4 = Mohan | first4 = H. | title = Pigmented nodular hidradenoma masquerading as nodular malignant melanoma. | journal = Dermatol Online J | volume = 14 | issue = 1 | pages = 15 | month =  | year = 2008 | doi =  | PMID = 18319032 |URL = http://dermatology.cdlib.org/141/case_presentations/hidradenoma/punia.html }}</ref>
*Superficial dermal lesion contiguous with the epidermis:
{{Main|Nodular hidradenoma}}
**Core of lesion:
***Cuboidal cells with round nuclei, eosinophilic-clear cytoplasm.
**Periphery of lesion:
***Surrounded by hyaline band.
***Peripheral palisading.


DDx:
==Trichoblastoma==
*[[Trichilemmal carcinoma]].
{{Main|Trichoblastoma}}
*[[Basal cell carcinoma]].
*[[Inverted follicular keratosis]].


Images:
==Trichofolliculoma==
*[http://ccr.cancer.gov/staff/images/9033_12822_Lee_1520.jpg Trichilemmoma - low mag. (cancer.gov)].<ref name=lee>URL: [http://ccr.cancer.gov/staff/gallery.asp?profileid=12822 http://ccr.cancer.gov/staff/gallery.asp?profileid=12822]. Accessed on: 2 September 2011.</ref>
{{Main|Trichofolliculoma}}
*[http://ccr.cancer.gov/staff/images/9033_12822_Lee_1521.jpg Trichilemmoma - high mag. (cancer.gov)].<ref name=lee/>
*[http://dermimages.med.jhmi.edu/images/trichilemmoma_1_060109.jpg Trichilemmoma (jhmi.edu)].<ref>URL: [http://dermatlas.med.jhmi.edu/derm/indexDisplay.cfm?ImageID=667496720 http://dermatlas.med.jhmi.edu/derm/indexDisplay.cfm?ImageID=667496720]. Accessed on: 2 September 2011.</ref>
*[http://www.flickr.com/photos/40981620@N04/3812019838/in/pool-1185084@N23/ Trichilemmoma - low mag. (flickr.com/Irlam)].
*[http://www.flickr.com/photos/40981620@N04/3812019930/in/pool-1185084@N23/ Trichilemmoma - intermed. mag. (flickr.com/Irlam)].
*[http://www.flickr.com/photos/40981620@N04/3811204517/in/pool-1185084@N23/ Trichilemmoma - high mag. (flickr.com/Irlam)].


==Eccrine poroma==
==Apocrine carcinoma of the skin==
===General===
===General===
*Benign tumour arising from the distal sweat duct.
*Rare.<ref name=pmid7678545>{{Cite journal  | last1 = Paties | first1 = C. | last2 = Taccagni | first2 = GL. | last3 = Papotti | first3 = M. | last4 = Valente | first4 = G. | last5 = Zangrandi | first5 = A. | last6 = Aloi | first6 = F. | title = Apocrine carcinoma of the skin. A clinicopathologic, immunocytochemical, and ultrastructural study. | journal = Cancer | volume = 71 | issue = 2 | pages = 375-81 | month = Jan | year = 1993 | doi =  | PMID = 7678545 }}</ref>
*Erythematous - gross.
*Usually very good prognosis.<ref name=pmid7678545/>


===Microscopic===
===Microscopic===
Features:<ref>URL: [http://www.pathconsultddx.com/pathCon/diagnosis?pii=S1559-8675(06)70190-5 http://www.pathconsultddx.com/pathCon/diagnosis?pii=S1559-8675(06)70190-5]. Accessed on: 2 July 2010.</ref>
Features:<ref name=pmid7678545/>
*Broad sheets of basaloid cells - attached to the epidermis - containing ductal structures - '''key feature'''.
*Nests.
*Biphasic stroma:
*Apocrine snouts - "decapitation secretion"
*#Edematous stroma.
*#Sclerotic stroma.
*Moderate nuclear pleomorphism.
*+/-Occasional mitoses.
 
Notes:
*Area above gland appears crusted.


DDx:
DDx:
*[[Trichilemmoma]].
*[[Paget disease of the breast]]/[[Extramammary Paget disease]].
*[[Nodular hidradenoma]].


Images:
====Images====
*[http://www.flickr.com/photos/40981620@N04/3808316834/in/photostream/ Eccrine poroma - low mag. (flickr.com)]
<gallery>
*[http://www.flickr.com/photos/40981620@N04/3807502071/in/photostream Eccrine poroma - intermed. mag. (flickr.com)].
Image:Apocrine_carcinoma_-_intermed_mag.jpg | Apocrine carcinoma - intermed. mag. (WC/Nephron)
 
Image:Apocrine_carcinoma_-_high_mag.jpg | Apocrine carcinoma - high mag. (WC/Nephron)
==Nodular hidradenoma==
</gallery>
*[[AKA]] ''eccrine acrospiroma''.<ref name=pmid18319032>{{Cite journal  | last1 = Punia | first1 = RP. | last2 = Garg | first2 = S. | last3 = Bal | first3 = A. | last4 = Mohan | first4 = H. | title = Pigmented nodular hidradenoma masquerading as nodular malignant melanoma. | journal = Dermatol Online J | volume = 14 | issue = 1 | pages = 15 | month =  | year = 2008 | doi =  | PMID = 18319032 |URL = http://dermatology.cdlib.org/141/case_presentations/hidradenoma/punia.html }}</ref>
===Stains===
===General===
Features:<ref name=pmid7678545/>
*Benign adnexal tumour.<ref name=pmid9537017>{{Cite journal  | last1 = Stratigos | first1 = AJ. | last2 = Olbricht | first2 = S. | last3 = Kwan | first3 = TH. | last4 = Bowers | first4 = KE. | title = Nodular hidradenoma. A report of three cases and review of the literature. | journal = Dermatol Surg | volume = 24 | issue = 3 | pages = 387-91 | month = Mar | year = 1998 | doi =  | PMID = 9537017 }}</ref>
*PAS +ve.
 
*PASD +ve.
Typical locations:<ref name=pmid18319032/>
*Scalp.
*Face.
*Trunk, anterior.
 
===Microscopic===
Features:<ref name=pmid9537017/>
*Well-circumscribed dermal lesions with:
**Back-to-back nests with a whorled appearance.
**Spaces between cells.
**Nuclei ovoid and centrally placed in the cell.
***No nucleolus.
**Cystic spaces with degenerated cells.
 
DDx:
*[[Eccrine poroma]].


===IHC===
===IHC===
Features:<ref name=pmid9537017/>
*[[GCDFP-15]] (gross cystic disease fluid protein-15) +ve.<ref name=pmid7678545/>
*CAM5.2 +ve.
*AE1/AE3 +ve.
*EMA +ve.
*S100 -ve.
*Desmin -ve.


==Trichoblastoma==
==Dermatomyofibroma==
*[[AKA]] ''trichoepithelioma''.
:Should ''not'' be confused with [[dermatofibroma]].
**''Trichoepithelioma'' is considered a superficial version of trichoblastoma; WHO lumps the two entities together.<ref name=Ref_Derm383>{{Ref Derm|383}}</ref>
*Abbreviated ''DMF''.
===General===
===General===
*Benign.
*Uncommon.
**Maligant counterpart of trichoepithelioma: [[trichilemmal carcinoma]].
*May be familial:
**Multiple familial trichoepithelioma.<ref name=pmid15289313>{{Cite journal  | last1 = Salhi | first1 = A. | last2 = Bornholdt | first2 = D. | last3 = Oeffner | first3 = F. | last4 = Malik | first4 = S. | last5 = Heid | first5 = E. | last6 = Happle | first6 = R. | last7 = Grzeschik | first7 = KH. | title = Multiple familial trichoepithelioma caused by mutations in the cylindromatosis tumor suppressor gene. | journal = Cancer Res | volume = 64 | issue = 15 | pages = 5113-7 | month = Aug | year = 2004 | doi = 10.1158/0008-5472.CAN-04-0307 | PMID = 15289313 }}</ref>
**Brooke-Spiegler syndrome.


===Microscopic===
===Microscopic===
Features:<ref>URL: [http://emedicine.medscape.com/article/1060049-workup#a0723 http://emedicine.medscape.com/article/1060049-workup#a0723]. Accessed on: 31 August 2011.</ref>
Features:<ref name=Ref_Derm504>{{Ref Derm|504}}</ref>
*Well-circumscribed cell nest in the superficial dermis.  
*Poorly formed fasicles parallel to the skin surface, usu. restricted to the superficial dermis.
*Surrounding by a fibrous stroma.
*Moderate cellular density - less cellular than [[DFSP]].
*Basaloid cells with [[peripheral palisading]].
*Eosinophilic cytoplasm.
*+/-Surround keratin-filled cysts.
*Fibroblasts-like cell aggregate, similar to a follicular papillae (papillary-mesenchymal body).
 
Notes:
*Very rarely an artefactual cleft - as in [[basal cell carcinoma]].
 
Variants:
*Desmoplastic trichoblastoma.


DDx:
DDx:
*[[Basal cell carcinoma]] - usu. mitoses, mucinous stroma and '''no''' papillary-mesenchymal bodies.
*[[DFSP]].
*[[Dermal cylindroma]] - has hyaline stroma.
*[[Dermatofibroma]].
*[[Trichofolliculoma]].


Images:
Images:
*[[WC]]:
*[http://www.dermpedia.org/node/8822 DMF - low mag. (dermpedia.org)].
**[http://commons.wikimedia.org/wiki/File:Trichoepithelioma_-_low_mag.jpg Trichoepithelioma - low mag. (WC)].
*[http://www.dermpedia.org/node/8824 DMF - high mag. (dermpedia.org)].
**[http://commons.wikimedia.org/wiki/File:Trichoepithelioma_-_high_mag.jpg Trichoepithelioma - high mag. (WC)].
 
===IHC===
Features:<ref name=Ref_Derm504>{{Ref Derm|504}}</ref>
*CD10 +ve.
*Vimentin +ve.


==Trichofolliculoma==
Others:<ref name=Ref_Derm504>{{Ref Derm|504}}</ref>
*CD34 -ve.
*Factor XIIIa -ve.
*S-100 -ve.


==Papillary eccrine adenoma==
*Abbreviated ''[[PEA]]''.
===General===
===General===
*Benign.
*Uncommon.
*Benign.<ref name=pmid857729>{{Cite journal  | last1 = Rulon | first1 = DB. | last2 = Helwig | first2 = EB. | title = Papillary eccrine adenoma. | journal = Arch Dermatol | volume = 113 | issue = 5 | pages = 596-8 | month = May | year = 1977 | doi =  | PMID = 857729 }}</ref>
 
Treatment:
*Excision.<ref>URL: [http://archderm.jamanetwork.com/article.aspx?articleid=541159 http://archderm.jamanetwork.com/article.aspx?articleid=541159]. Accessed on: 10 December 2012.</ref>
===Gross===
*Central location.
 
Note:
*The ''digital papillary adenoma'' is considered malignant; the AFIP says these are best classified as ''adenocarcinomas'', i.e. ''[[digital papillary adenocarcinoma]]''.<ref name=pmid10843279>{{Cite journal  | last1 = Duke | first1 = WH. | last2 = Sherrod | first2 = TT. | last3 = Lupton | first3 = GP. | title = Aggressive digital papillary adenocarcinoma (aggressive digital papillary adenoma and adenocarcinoma revisited). | journal = Am J Surg Pathol | volume = 24 | issue = 6 | pages = 775-84 | month = Jun | year = 2000 | doi =  | PMID = 10843279 }}</ref>


===Microscopic===
===Microscopic===
Features:<ref name=Ref_Derm382>{{Ref Derm|382}}</ref>
Features:<ref name=pmid17642667>{{Cite journal  | last1 = Laxmisha | first1 = C. | last2 = Thappa | first2 = DM. | last3 = Jayanthi | first3 = S. | title = Papillary eccrine adenoma. | journal = Indian J Dermatol Venereol Leprol | volume = 70 | issue = 6 | pages = 370-2 | month =  | year =  | doi =  | PMID = 17642667 | URL = http://www.ijdvl.com/article.asp?issn=0378-6323;year=2004;volume=70;issue=6;spage=370;epage=372;aulast=Laxmisha }}</ref><ref name=pmid9793207/>
*Irregular hair follicle (basilar nest of cells with an acellular hair shaft) with:
*Well-circumscribed lesions consisting of multiple cystic spaces lined by a bilayered epithelium with:
**Smaller satellites (follicles) consisting of well-circumscribed basilar cells.
**Papillary projections into the lumen.
**Amorphous eosinophilic material in the cystic spaces.
**Surrounded by a fibrous stroma.<ref name=pmid9508346>{{Cite journal  | last1 = Mizuoka | first1 = H. | last2 = Senzaki | first2 = H. | last3 = Shikata | first3 = N. | last4 = Uemura | first4 = Y. | last5 = Tsubura | first5 = A. | title = Papillary eccrine adenoma: immunohistochemical study and literature review. | journal = J Cutan Pathol | volume = 25 | issue = 1 | pages = 59-64 | month = Jan | year = 1998 | doi =  | PMID = 9508346 }}</ref>


Note:
Note:
*Lack artificial clefting between the (basilar) nests and stroma (seen in [[BCC]]).
*May appear to have more than two cell layers.
*Surrounding stroma does not have a basophilic tingle (seen in [[BCC]]).  


DDx:
DDx:
*[[Trichoblastoma]].
*[[Digital papillary adenocarcinoma]] - location important.
*[[Basal cell carcinoma]].
*[[Tubular apocrine adenoma]] (tubulopapillary hidradenoma<ref name=pmid1566975>{{Cite journal  | last1 = Fox | first1 = SB. | last2 = Cotton | first2 = DW. | title = Tubular apocrine adenoma and papillary eccrine adenoma. Entities or unity? | journal = Am J Dermatopathol | volume = 14 | issue = 2 | pages = 149-54 | month = Apr | year = 1992 | doi =  | PMID = 1566975 }}</ref>) - a related tumour.<ref name=pmid8238787>{{Cite journal  | last1 = Ishiko | first1 = A. | last2 = Shimizu | first2 = H. | last3 = Inamoto | first3 = N. | last4 = Nakmura | first4 = K. | title = Is tubular apocrine adenoma a distinct clinical entity? | journal = Am J Dermatopathol | volume = 15 | issue = 5 | pages = 482-7 | month = Oct | year = 1993 | doi =  | PMID = 8238787 }}</ref>


Images:
Image:
*[http://www.dermatopathonline.com/trichofolliculoma2.html Trichofolliculoma - several images (dermatopathonline.com)].
*[http://www.ijdvl.com/viewimage.asp?img=ijdvl_2004_70_6_370_13482_2.jpg PEA - crappy image (ijdvl.com)].<ref name=pmid17642667/>
*[http://commons.wikimedia.org/wiki/File:SkinTumors-P6190340.JPG Trichofolliculoma (WC)]. (???)


==Apocrine carcinoma of the skin==
===IHC===
===General===
Outer layer of epithelium:<ref name=pmid9508346/>
*Rare.<ref name=pmid7678545>{{Cite journal  | last1 = Paties | first1 = C. | last2 = Taccagni | first2 = GL. | last3 = Papotti | first3 = M. | last4 = Valente | first4 = G. | last5 = Zangrandi | first5 = A. | last6 = Aloi | first6 = F. | title = Apocrine carcinoma of the skin. A clinicopathologic, immunocytochemical, and ultrastructural study. | journal = Cancer | volume = 71 | issue = 2 | pages = 375-81 | month = Jan | year = 1993 | doi =  | PMID = 7678545 }}</ref>
*SMA-alpha +ve.  
*Usu. very good prognosis.<ref name=pmid7678545/>
*Keratin 14 +ve.  
Inner layer of epithelium:<ref name=pmid9508346/>
*Keratin 8 +ve.


===Microscopic===
Other stains:<ref name=pmid9793207>{{Cite journal  | last1 = Guccion | first1 = JG. | last2 = Patterson | first2 = RH. | last3 = Nayar | first3 = R. | last4 = Saini | first4 = NB. | title = Papillary eccrine adenoma: an ultrastructural and immunohistochemical study. | journal = Ultrastruct Pathol | volume = 22 | issue = 3 | pages = 263-9 | month =  | year =  | doi =  | PMID = 9793207 }}</ref>
Features:<ref name=pmid7678545/>
*Vimentin +ve.
*Nests.
*CEA +ve.
*Apocrine snouts - "decapitation secretion"
*[[EMA]] +ve.
 
*S-100 +ve.
DDx:
*[[Paget disease of the breast]]/[[Extramammary Paget disease]].


Images:
===Sign out===
*[http://commons.wikimedia.org/wiki/File:Apocrine_carcinoma_-_intermed_mag.jpg Apocrine carcinoma - intermed. mag. (WC)].
<pre>
*[http://commons.wikimedia.org/wiki/File:Apocrine_carcinoma_-_high_mag.jpg Apocrine carcinoma - high mag. (WC)].
SKIN LESION, LEFT PARIETAL SCALP, BIOPSY:
- PAPILLARY ECCRINE ADENOMA.
</pre>


===Stains===
====Micro====
Features:<ref name=pmid7678545/>
The sections show a well-circumscribed multi-locular superficial dermal lesion with a bilayered epithelium and intracystic papillary projections. The cystic spaces contain amorphous eosinophilic material. The cystic component is surrounded by a dense fibrous stroma with a mixed inflammatory infiltrate, consisting primary of plasma cells and lymphocytes.
*PAS +ve.
*PASD +ve.


===IHC===
There is no significant nuclear atypia and no mitotic activity is appreciated. The overlying epidermis matures appropriately. A granular layer is present.
*GCDFP-15 (gross cystic disease fluid protein-15) +ve.<ref name=pmid7678545/>


=See also=
=See also=
Michael
48,460

edits

Retrieved from "https://librepathology.org/wiki/Special:MobileDiff/16452...49062"

Navigation menu