Block 4 Flashcards
Bullous pemphigoid.
60s-70s
Blistering due to autoantibodies against BPAG2
Subepidermal blisters
Non-acantholytic
Linear deposition of IgG and C3 leads to ribbon candy appearance
Negative Nikolsky sign
Pemphigus vulgaris.
30s-40s
IgG autoantibodies against desmogleins 1 and 3
Acantholysis
Suprabasal blistering
Tombstone appearance left
Positive Nikolsky sign (rubbing causes split)
Dermatitis herpetiformis.
Associated with gluten sensitivity enteropathy
IgA antibodies against gluten form in gut and fix on skin
Destruction of laminin and type IV collagen
Subepidermal blister and papillary microabscesses
Presence of enzyme tissue transglutaminase (tTG)
Psoriasis.
Association with HLA-Cw*0602 allele
Keratinocyte proliferation
Elongation of rete ridges
Acanthosis
Parakerarosis (nuclei in outer keratinocytes)
Monroe’s microabscesses in superficial epidermis
Thinning of stratum granulosum
Salmon coloured plaque covered loosely by silver-white scales
Lichen planus.
Expression of altered antigens at basal layer and epidermo-dermal junction
Pruritic, purple, polygonal, planar papules, and plaques
Lace-like reticulate pattern (white)
Self limiting
No definitive border at rete ridges (saw tooth) Band-like lymphocytic infiltration Civatte bodies (apoptotic epidermal cells)
Cutaneous squamous cell carcinoma.
Malignancy from supra basal epidermal keratinocytes
Keratin pearls
Well differentiated
In situ - can invade (islands of atypical cells in dermis)
Ulcerations
Keratocanthoma.
Squamous cell carcinoma
Rapid growth
Large, smooth, dome-shaped verrucous nodule with a central keratotic crater
Spontaneous resolution; however can be locally destructive
Verrucous carcinoma.
Squamous cell carcinoma
Slow growing
Cauliflower appearance
Oral cavity, larynx, genitalia, skin, esophagus
Well differentiated; minimal met potential
Turns aggressive if treated with radiation
Basal cell carcinoma.
Slow growing; rarely metastasize
PTCH gene mutation
Morphology: pearly, translucent, telangietic, pallisading
Ulceration in advanced stages
Invades rather than metastasizes
Hypospadias.
External meatus opens on underside of penis
Failure of fusion of the urethral folds on the undersurface of the genital tubercle
Seminoma.
Germ cell tumor
Associated with isochromosome 12p, OCT3/4, NANOG, PLAP, and c-kit activating mutations
Fried egg appearance
Can produce beta-hCG (synctiotrophoblasts)
Painless testicular mass
Do not produce AFP
Mets to retro peritoneal LNs
Non-seminomatous: embryonal carcinoma.
Undifferentiated and pluripotent More aggressive than seminomas Small nodular lesions PLAP, cytokeratin, OCT3/4, CD30 Negative for c-kit Painful
Non-seminomatous: yolk sac tumor.
> 3 years old
Non-encapsulated, homogeneous yellow-white
Schiller-Duval bodies (glandular pattern of two layers)
AFP and alpha1-antitrypsin
