View source for Suspected malignant skin excisions

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|author1=[[User:Mikael Häggström|Mikael Häggström]]
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Suspected malignant '''[[skin]]''' excisions:
{{Fixation - standard}}
{{Fixation - general notes}}
==Common targets==
If directly suspected from the referral, see:
*Melanoma
:*[[Melanoma in situ]]
:*[[Invasive melanoma of the skin]]
*[[Basal-cell carcinoma]]
*[[Squamous-cell carcinoma of the skin]]

==Gross processing==
{{Basic gross evaluation of suspected malignant skin lesions}}
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File:Dark skin focalities.jpg|link=Dark skin focalities|See separate article in case of '''[[dark skin focalities]]'''
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{{Tissue selection from suspected malignant skin lesions}}
==Microscopic evaluation==
If the lesion was pigmented on gross examination, evaluate as a '''[[dark skin focality]]'''. If not:

Look for atypical cells, possibly by scrolling through the epidermis at intermediate magnification and then through the dermis at a lower magnification. If atypical cells are found, look for:
*Similarity to epidermal basal cells, evaluate as suspected '''[[basal-cell carcinoma]]'''
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File:High-magnification micrograph of basal-cell carcinoma.jpg|[[Basal-cell carcinoma]]
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*Similarity to squamous cells: See below:
{{Squamous-cell like proliferations - differential diagnosis}}

===General benign imitators of skin malignancy===
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File:Histopathology of granulomatous inflammation by a ruptured inclusion cyst.jpg|'''[[Granulomatous skin inflammation]]''' often contains giant cells that may appear atypical.
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===Further workup of malignant findings===
In case of skin cancer, determine whether the peripheral/radial and deep margins are clear, close or continuous.<ref name=rcpath>{{cite web|url=https://www.rcpath.org/asset/53688094-791E-4AAA-82CEC42C3CB65E35/|author=David Slater, Paul Barrett|title=Standards and datasets for reporting cancers - Dataset for histopathological reporting of primary cutaneous basal cell carcinoma|website=The Royal College of Pathologists}} February 2019</ref><ref group=note>"Peripheral" or "radial" margins are preferred rather than "lateral", since a "lateral" margin may be interpreted as opposite to the "medial margin".</ref> A close margin has various definitions for different malignancies, but for [[basal-cell carcinoma]] and [[cutaneous squamous cell carcinoma]] it is defined as being closer than 1 mm from the edge (but yet non-continuous with it),<ref name=rcpath/><ref name=Elliott2018>1 mm as cutoff for close margin: {{cite web|title=Cutaneous squamous cell carcinoma: predictors of positive and close margins and outcomes of re-excision in Northland, New Zealand|author=Brodie M Elliott, Benjamin R Douglass, Daniel McConnell, Blair Johnson, Christopher Harmston|title=New Zealand Medical Journal|volume=131|issue=1487|date=2018-12-14|url=https://www.nzma.org.nz/journal-articles/cutaneous-squamous-cell-carcinoma-predictors-of-positive-and-close-margins-and-outcomes-of-re-excision-in-northland-new-zealand}}</ref> but 2-3 mm for [[melanoma of the skin|melanoma]].<ref name=busam2018a>[https://books.google.se/books?id=oepmDwAAQBAJ&pg=PA406 Page 406] in: {{cite book|title=Pathology of Melanocytic Tumors|author=Klaus J. Busam, Richard A Scolyer, Pedram Gerami|publisher=Elsevier Health Sciences|year=2018|isbn=9780323508681}}</ref>

===Previous biopsy===
{{Moderate-begin}}At least if there is a known previous biopsy, look for changes that are consistent with a biopsy site, to confirm that it was taken from the excised area.{{Moderate-end}} Such changes in the skin include:
*Granulation tissue in more fresh biopsies
*Dense collagen
*Fibrosis with vertical blood vessels
*Fibrosis that replaces [[solar elastosis]]

==Reporting==
''Preferably see specific article on the condition at hand, if available.''
*Optionally, the presence of a keratinized squamous '''epithelium'''.
*Any '''abnormalities''', generally preceded by location in terms of epidermal, dermal or more specific layers thereof.
*If '''malignant''':
:*Degree of '''differentiation'''
{{Skin radicality report|indentation=yes|margin=___|margin-comment=Definitions vary for the distance as per [[#Further workup of malignant findings|Further workup of malignant findings]] above|exactness-ref=<ref name=rcpath/>}}
:For skin shave biopsies, non-radicality may be reported as: "Extending to base and peripheral edges of biopsy" (as they may not be regarded as "margins" on a biopsy).
:*'''Perineural''' or '''vascular invasion''' if present.
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