Skin Neoplasias - Plaza Flashcards
Seborrheic Keratoses
What is the etiology?
Describe its appearance & distribution.
What is the signifiance of multiple SKs?
Seborrheic Keratoses
FGFR3 mutation. (very common)
A “stuck-on” warty appearance on sun-exposed skin of the elderly. Hyperkeratotic and papillomatous.
This is a Leser-Trelat sign, indicative of an underlying gastric carcinoma.
Actinic Keratosis
Describe their appearances grossly and microscopically.
How dangerous are they?
Actinic Keratosis
Erythematous yello/brown scaly lesions, with atypia of the stratum basale. Parakeratosis & Solar elastosis.
0-10% become malignant (watch for full-thickness atypia >> SCC).
Squamous Cell Carcinoma
What are the cause & predisposing factors?
How dangerous are they?
Squamous Cell Carcinoma
UVB damage, but also local damage, viral infection, immunosuppression. (Marjolin’s Tumor = SCC due to burn or ulcer)
About 5% can metastasize. Normally does not bypass BMZ.
Squamous Cell Carcinoma
Describe its gross appearance.
Describe its microscopic appearance.
Squamous Cell Carcinoma
Sharply defined red scaly plaque; sometimes nodular or ulcerative (bad).
Full thickness atypia, contained to epithelium (in situ), unless invasive.
Keratoacanthoma
Describe its structure & appearance.
Describe its progression. Is treatment indicated?
How will this affect an immunocompromised patient?
Keratoacanthoma
Crater-shaped nodule filled with keratin. Well differentiated & with good pallor.
Radidly growing, and often rapidly resolving. But, can cause extensive local damage (treatment advocated).
If immunocompromised >> Multiple keratoacanthomae.
What is the most common cancer in humans?
Basal Cell Carcinoma
Basal Cell Carcinoma
Describe its etiology.
How dangerous are they?
Basal Cell Carcinoma
Dysregulation of Shh/PTCH pathway, secondary to sun exposure.
Not at all; only really metastasizes in the immunocompromised.
Basal Cell Carcinoma
Describe its gross appearance.
Describe its microscopic appearance.
Basal Cell Carcinoma
Pearly papule with prominent telangiectasias.
Expansion of epithelial cells from the stratum basale(?)
Melanocytic Nevi
Describe the 3 histologically distinct subsets.
Which subset is the most “mature”?
Melanocytic Nevi
Junctional, Compound, Intradermal.
Nevi tend to migrate deep to the epidermis; intradermal tend to be more mature.
Distinguish dysplastic nevi from acquired nevi. Focus on appearance, etiology, and outcomes.
Dysplastic nevi are present from birth, either as a familial or sporadic form. They are more numerous & irregular, larger, and provide a higher risk for melanoma than acquired nevi do.
Distinguish familial and sporadic dysplastic nevus syndromes.
Sporadic features fewer nevi with a smaller risk of melanoma (10%).
Familial results from AutDom mutation in CDKN2A; more nevi and higher risk (100%).
Melanoma
Describe its etiology.
Who is at highest risk?
What factors are important to its description?
Melanoma
Usually a result of sun damage (multifactorial), causing activation of BRAF in melanocytes.
Older, fair-skinned individuals, albinos, and those with dysplastic nevus syndome or excision repair defects (XP).
ABCDE (asym, borders, color, diameter, evolutions)
Melanoma
Describe the process by which it can proliferate and metastasize.
What is the Breslow thickness?
Melanoma
Initial radial growth phase occurs within epidermis (non-metastatic). Vertical growth phase extends into dermis (potentially metastatic).
Breslow thickness = depth of invasion. >1.7mm = higher risk for metastasis. >1.00mm = biopsy the sentinel lymphatics.
Melanoma
Describe the 4 mentioned subtypes.
Melanoma
Superficial spreading: Most common, in back/extremities. Low-risk.
Nodular: NO radial growth phase. Poor prognosis.
Lentigo Maligna: Involves the head & neck.
Acral Lentiginous: Palm/sole/nailbed of AfAm patients. No UV involvement?
Mycosis Fungoides
Describe its etiology.
Describe its progression.
Who is at highest risk?
Mycosis Fungoides
A T-cell lymphoma that invades the dermis & epidermis.
Patch > Plaque > Tumor stages. All may be copresent. Sometimes chronic.
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