Non-malignant skin disease
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.
General classification (Inflammatory)
- Bullous.
- Interface.
- Nodular & diffuse.
- Spongiotic.
- Vasculitis.
- Perivascular.
- Panniculitis.
- Psoriasiform.
Tabular comparison of inflammatory skin disease (adapted from Brister[1]):
Pattern | Key histologic feature | Subclassifications | Example |
Bullous | "Empty space" | -Subcorneal -Suprabasillar -Subepidermal |
-? -? -? |
Interface | Inflammation at DE junction | -Vacuolar (minimal) -Lichenoid (band-like) |
-Erythema multiforme -Lichen simplex chronicus (LSC) |
Nodular & diffuse | Nodular & diffuse | ? | |
Spongiotic | Edema between keratinocytes | -Acute -Subacute -Chronic |
-Poison Ivy -Nummular dermatitis -Atopic dermatitis |
Vasculitis | Inflammation of vessel wall | ? | ? |
Perivascular | Inflammation around vessels | ? | ? |
Panniculitis | Inflamm. of SC tissue | -Septal -Nodular |
|
Psoriasiform | Epidermal thickening and long rete ridges |
-Regular -Irregular |
Notes:
- DE junction = dermal-epidermal junction.
- The "empty space" in bullous disease in situ is filled with fluid.
Lichen planus
General
Etiology:
- Autoimmune disease, T-cell–mediated.[4]
Microscopy
Features:[5]
- Loss of basal cells (stratum basale) -- key feature.
- Loss of rete ridges.
- Interface dermatitis (lymphocytes at dermal-epidermal junction).
Images:
Lichen sclerosus
- AKA chronic atrophic vulvitis - vulvar lesion; balanitis xerotica obliterans (BXO) - penile lesion.[6]
Microscopic
Key feature:[7]
- Subepithelial fibrosis.
Squamous cell hyperplasia
General
- Variant of spongiotic dermatitis.[9]
Etiology:[10]
- Pruritus (itchness) -> mechanical trauma -> lichenification (thickened/leathery[11].
Microscopic
Features:[7]
- Acanthosis (epithelial thickening).
- Hyperkeratosis.
Other features:[12]
- Spongiosis (epidermal intercellular edema -- cells appear to have a clear halo around 'em).
- Parakeratosis = retention of nuclei in the stratum corneum.
Images:
Seborrheic keratosis
General
- Benign.
- Common.
Epidemiology
- Old people.
Gross
- "Stuck-on" appearance - raised lesion.
Image(s):
Microscopic
Features:
- Normal appearing epidermis - raised above skin surface.
- "Horn cysts" - collections of keratin.
Image(s):
- Seborrheic keratosis (WC).
- Seborrheic keratosis - high mag. (dermatlas.org).
- Seborrheic keratosis - low mag. (dermatlas.org).
Verruca vulgaris
General
- AKA Wart.
- Etiology: HPV. (???)
Microscopic
Features:
- Hyperkeratosis (more keratin - thick stratum corneum).
- Hypergranulosis (thicker stratum granulosum).
- Rete ridges lengthened (~7-10x normal).
- Acanthosis (thickening of the stratum spinosum).
- Large blood vessels at the dermal-epidermal junction.
Ref.:[13]
Molluscum contagiosum
- Etiology: caused by molluscum contagiosum virus.
Microscopic
Features:
- A suprabasilar epidermal lesion consisting of "molluscum bodies", i.e. molluscum bodies are found above the stratum basale.[14]
- Molluscum bodies:
- Large cells with abundant granular eosinophilic cytoplasm.
- Small peripheral nucleus.
Image(s):
Note:
- Molluscum bodies vaguely resemble signet ring cells -- but:
- Cytoplasm eosinophilic and granular.
- Nucleus usually smaller than in signet ring cell.
- Molluscum bodies are only the epidermis - an uncommon place to find SRCs without finding them elsewhere.
- The granular eosinophilic cytoplasm represents accumulated virons.
Dermal nevus
- Think melanoma.
Clinical: ABCD = asymmetric, borders (irregular), colour (black), diameter (large).
Microscopic
Features:[15]
- Symmetrical lesion.
- "Matures" with depth - less cellular, less atypia.
- No destruction of surrounding structures.
- Only in dermis key feature.
- Otherwise it is something else, e.g. dermal nevus, junctional nevus.
Microscopic
- Basaloid cells mixed with squamous cells.
- Keratin-filled invaginations.
- Horn cysts - intraepidermal, brown globule-like structures.
- Melanocytes at the dermoepidermal junction.[16]
Pilomatrixoma
General
- Benign skin tumour.
- Most common solid skin tumour of children.[17]
Clinical:
- Hard nodule - calcification.
- +/-Painful. (???)
Treatment:
- Surgical excision.[17]
Microscopic
Features:[18]
- Location: lower dermis/subcutaneous fat; thus, usu. surrounded by connective tissue.
- Sharpy demarcated island of cells.
- Calcification in 75% - with calcium staining (von Kossa).
- Cells:[19]
- Basaloid epithelial cells - have prominent nucleoli.
- Anucleate squamous cells ("ghost cells").
- Giant cell foreign body type granulomas (form in reaction to keratin).
Notes:
- Keratin a prominent feature on cytology - lots of orange stuff.
Images:
DDx:
- Epidermal inclusion cyst.
Syringoma
General
- Benign sweat duct tumour.
- Eccrine differentiation.
- Usually close to lower eyelid.[20]
Microscopic
Features:[21]
- Proliferation of benign ducts with lined by a bilayer (as in normal sweat ducts) with abnormal architecture:
- Tadpole like appearing ducts.
Image:
Inverted follicular keratosis
- Benign skin lesion.
- Rare.
- May mimic squamous cell carcinoma or basal cell carcinoma.[22]
Images:
- Inverted follicular keratosis - low mag. (flickr.com).
- Inverted follicular keratosis - high mag. (flickr.com).
Dermal cylindroma
General
- Benign skin lesion.
- Should not be confused with cylindroma (adenoid cystic carcinoma).
Microscopic
Features:
- Nests of cells that are surrounded by hyaline (i.e. glassy, eosinophilic, acellular) material.
Images:
Keratoacanthoma
- Abbreviated KA.
- Generally considered to be benign.
- Rare reports of metastases suggesting it may be a form of squamous cell carcinoma.[23]
Clinical
- May grow rapidly (weeks or months) then involute.
- Main DDx is squamous cell carcinoma.
- Exophytic lesion, well-circumscribed.
Microscopic
Features:[24]
- 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.
Image:
Dermatofibroma
General
- AKA fibrous histiocytoma.
- Reactive process -- it is not a neoplasm.
- Usually assoc. with previous trauma.
- In women... usually legs.
Microscopic
Features:[25]
- Prominent fibrous bundles, especially at the edge of the lesion.
- Surrounded by spindle cells (fibroblasts).
- Usually thought of as fibroblasts surrounded by fibrous material ("collagen-trapping").
- Surrounded by spindle cells (fibroblasts).
- Lack of adnexal structures, i.e. no sweat glands, no hair.
- +/-Acanthosis (thickened epithelial layer - specifically thickened stratum spinosum) with basal keratinocyte hyperpigmentation.
- May vaguely resemble basal cell carcinoma.
Images:
DDx:
- Neurofibroma.
- Blue nevus.
- Dermatofibroma pertuberans (DFSP).
- Melanoma.
Superficial dermal infiltrates
Discussed in detail by Alsaad and Ghazarian.[26]
Dermal perivascular lymphoeosinophilic infiltration (DPLI)
- Microscopic appearance is just what it is called:
- Lymphocytes and eosinophils around the vessels in the superficial dermis.
DDx:[26]
- Insect bite - classically wedge-shaped.[27]
- Drug reactions.
- Urticarial reactions.
- Prevesicular early stage of bullous pemphigoid.
- HIV related dermatoses.
Notes:
- May superficially resemble cutaneous lymphoma.[27]
Images:
Congenital dermal melanocytosis
- AKA Mongolian spots.
- Classically seen in asian children.
Gross:
- Brown or blue-grey patch in the lumbosacral area.
Palmar fibromatosis
General
- AKA Dupuytren's contracture.
Clinical:[28]
- Usually older 60-70s.
- Male > female.
- Associated with:
- Alcohol abuse.
- May be familial.
Microscopic
Features:[29]
- Bland spindle cells in dense collagen.
- No nuclear atypia.
- Giant cells.
- +/-Mitotic figures.
Images:
Bullous disease
Cysts
See also
References
- ↑ Brinster NK (March 2008). "Dermatopathology for the surgical pathologist: a pattern based approach to the diagnosis of inflammatory skin disorders (part I)". Adv Anat Pathol 15 (2): 76–96. doi:10.1097/PAP.0b013e3181664e8d. PMID 18418089.
- ↑ Teichman, JM.; Sea, J.; Thompson, IM.; Elston, DM. (Jan 2010). "Noninfectious penile lesions.". Am Fam Physician 81 (2): 167-74. PMID 20082512.
- ↑ Gupta, R.; Bansal, B.; Singh, S.; Yadav, I.; Gupta, K.; Kudesia, M. (2009). "Lichen planus of uterine cervix - the first report of a novel site of occurrence: a case report.". Cases J 2: 9306. doi:10.1186/1757-1626-2-9306. PMID 20062629.
- ↑ URL: http://emedicine.medscape.com/article/1078327-overview. Accessed on: 11 September 2010.
- ↑ URL: http://emedicine.medscape.com/article/1078327-overview. Accessed on: 11 September 2010.
- ↑ Finkbeiner AE (January 2003). "Balanitis xerotica obliterans: a form of lichen sclerosus". South. Med. J. 96 (1): 7–8. PMID 12602704.
- ↑ 7.0 7.1 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. 1065-6. ISBN 0-7216-0187-1.
- ↑ Kumar, Vinay; Abbas, Abul K.; Fausto, Nelson; Aster, Jon (2009). Robbins and Cotran pathologic basis of disease (8th ed.). Elsevier Saunders. pp. 1011. ISBN 978-1416031215.
- ↑ Tadrous, Paul.J. Diagnostic Criteria Handbook in Histopathology: A Surgical Pathology Vade Mecum (1st ed.). Wiley. pp. 296. ISBN 978-0470519035.
- ↑ URL: http://emedicine.medscape.com/article/1123423-overview. Accessed on: 20 August 2010.
- ↑ URL: http://www.medterms.com/script/main/art.asp?articlekey=10131. Accessed on: 20 August 2010.
- ↑ URL: http://emedicine.medscape.com/article/1123423-diagnosis. Accessed on: 20 August 2010.
- ↑ URL: http://missinglink.ucsf.edu/lm/DermatologyGlossary/verruca_vulgaris.html. Accessed on: 14 July 2010.
- ↑ http://www.missionforvisionusa.org/anatomy/2006/08/what-is-molluscum-contagiosum.html
- ↑ need ref
- ↑ http://emedicine.medscape.com/article/1059477-overview
- ↑ 17.0 17.1 http://emedicine.medscape.com/article/1058965-overview
- ↑ http://emedicine.medscape.com/article/1058965-diagnosis
- ↑ http://www.bccancer.bc.ca/HPI/CE/cytotechnology/cytosleuthquiz/nongyne/ngcase02d.htm
- ↑ Kumar, Vinay; Abbas, Abul K.; Fausto, Nelson; Aster, Jon (2009). Robbins and Cotran pathologic basis of disease (8th ed.). Elsevier Saunders. pp. 1177. ISBN 978-1416031215.
- ↑ URL: http://emedicine.medscape.com/article/1059871-diagnosis. Accessed on: 12 May 2010.
- ↑ URL: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC475744/. Accessed on: 11 May 2010.
- ↑ Mandrell JC, Santa Cruz D (August 2009). "Keratoacanthoma: hyperplasia, benign neoplasm, or a type of squamous cell carcinoma?". Semin Diagn Pathol 26 (3): 150–63. PMID 20043514.
- ↑ Klatt, Edward C. (2006). Robbins and Cotran Atlas of Pathology (1st ed.). Saunders. pp. 378. ISBN 978-1416002741.
- ↑ 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.
- ↑ 26.0 26.1 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.
- ↑ 27.0 27.1 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.
- ↑ URL: http://www.humpath.com/palmar-fibromatosis. Accessed on: 6 January 2011.
- ↑ URL: [1]. Accessed on: 6 January 2011.
- ↑ Wang L, Zhu H (2006). "Clonal analysis of palmar fibromatosis: a study whether palmar fibromatosis is a real tumor". J Transl Med 4: 21. doi:10.1186/1479-5876-4-21. PMC 1488873. PMID 16696857. http://www.biomedsearch.com/nih/Clonal-analysis-palmar-fibromatosis-study/16696857.html.