Flashcards in Skin Deck (352)
Loading flashcards...
300
Epithelioid angiosarcoma vs. epithelioid hemangioma.
Epithelioid hemangioma:
− Symmetrical.
− No nuclear atypia.
301
Angiosarcoma: Immunohistochemistry (4).
CD31, CD34, ERG.
Lymphatic tumors: D2-40.
302
Angiosarcoma: Electron microscopy.
Weibel-Palade bodies (rod-shaped; resemble lysosomes).
303
Dabska tumor.
Malignant intravascular papillary angioendothelioma.
304
Angioleiomyoma: Anatomic site.
Extremities, esp. lower extremities.
305
Dartoic leiomyoma:
A. Anatomic sites.
B. Clinical presentation.
A. Scrotum, labium majus, areola.
B. Painless (unlike other leiomyomas).
306
Cutaneous leiomyosarcoma:
A. Age group.
B. Anatomic sites.
A. Second and third decades.
B. No anatomic predilection.
307
Cutaneous leiomyosarcoma:
A. Histologic architecture.
B. Metastasis.
A. Asymmetrical; forms fascicles; intermixed zones of hypercellularity and of better differentiation.
B. Hematogenous.
308
Keloid: Change in histology with age.
Early lesions: More vascular.
Older lesions: More fibrous.
309
Keloid vs. hypertrophic scar.
Hypertrophic scar:
− Limited to area of injury.
− Less myxoid matrix.
310
Dermatofibrosoma: Clinical sign.
Fitzpatrick's sign: Pinching the lesion results in a dimple.
311
Dermatofibroma: Aneurysmal variant.
Vascular proliferation and hemosiderin.
312
Dermatofibroma: Cellular type.
Densely cellular; increased mitotic figures.
313
Dermatofibroma: Immunohistochemistry.
Positive: Factor XIIIa.
Negative: CD34 (except at periphery of cellular DF).
314
Dermatofibrosarcoma protuberans: Change in clinical appearance with age.
Early: Tan or brown nodule, slow-growing.
Later: Blue-red, multilobular nodule, rapidly growing.
315
Dermatofibrosarcoma protuberans:
A. Overlying epidermis.
B. Invasion of fat.
C. Cytological atypia and mitosis.
A. Atrophic.
B. Replacement or lacelike infiltration.
C. Present but not prominent.
316
Dermatofibrosarcoma protuberans: Translocation.
t(17;22) :: COL1A1−PDGFB.
317
Dermatofibrosarcoma protuberans: Variant.
Bednar tumor contains pigmented spindle cells.
318
Neurofibroma: Preferred anatomic sites (2).
Palms, soles.
319
Neurofibroma: Cellular components.
Schwann cells.
Fibroblasts.
(Mast cells in the background.)
320
Schwannoma: Zones of Antoni.
Antoni A: Hypercellular.
Antoni B: Hypocellular; mucinous background.
321
Dermatofibroma vs. neurofibroma: Overlying epidermis.
DF: Hyperplastic, with pigmented basal cells.
NF: Atrophic, with indistinct rete ridges.
322
Merkel-cell carcinoma: Anatomic sites.
Head.
Extremities.
323
Merkel-cell carcinoma: Associated epithelial malignancy.
Squamous-cell carcinoma.
324
Merkel-cell carcinoma: Cytokeratin stain.
Positive for CK20.
325
Merkel-cell carcinoma: Electron microscopy.
Membrane-bound dense granules; perinuclear bundles or whorls of intermediate filaments.
326
Merkel-cell carcinoma: Divergent differentiation (3).
Squamous.
Adnexal.
Melanocytic.
327
Urticaria pigmentosa: Four forms.
Arising in infancy or childhood without systemic lesions.
Arising in adolescence or adulthood without systemic lesions.
Systemic mast-cell disease.
Mast-cell leukemia.
328
Urticaria pigmentosa: Age group in which ___ lesions appear.
A. solitary
B. diffuse erythrodermic
C. telangiectasia macularis eruptiva perstans
A, B. Infants.
C. Adults.
329
