Path differentials

Question 1

Spindle cell neoplasms differential:

Answer 1

• LADDS (come on now LADDS!!!)
• leiomyosarcoma (will stain positive for SMA)
• AFX (+ for CD 10, + CD 68, should stain S-100 negative, and cytokeratin negative to exclude melanoma and SCC)
• Desmoplastic melanoma (will stain S-100 positive- look for insitu component)
• DFSP ( cd 34+, factor 13a -, spindle cells in storiform pattern)
• Spindled squamous cell carcinoma (look for in-situ component)

Question 2

Differential for severe papillary dermal edema:

Answer 2

• Sweets
• cellulitis
• PMLE
• Pernio
• AGEP

Question 3

Differential diagnosis for neutrophilic abscesses in the dermal papilla:

Answer 3

BLLED:

• Bullous Pemphigoid
• Lupus (bullous)
• Linear IgA
• EBA
• DH

Question 4

Differential diagnosis for Acantholytic Dyskeratosis:

Answer 4

DAWGS Holler

• Dariers
• Acantholytic acanthoma, actinic keratosis
• Warty dyskeratoma
• Grovers
• SCC
• Hailey Hailey

Question 5

Differential for palisading granulomatous dermatitis:

Answer 5

DINGAR

• Deep GA
• Infection (look for lots of nuetrophils, then get stains)
• NL (palisading granulomas in layers of cake), NXG (lots of necrobiosis)
• GA (palisading granulomas around necrobiotic collagen, stain for mucin, may see eos), Gout
• Actinic granuloma
• Rheumatoid nodules (granulomas surround deep pink fibrinoid material)