An ecchymotic nodule on the scalp of an elderly male mimicking angiosarcoma
Saleh J, Friedman B. An ecchymotic nodule on the scalp of an elderly male mimicking angiosarcoma. American Journal of Dermatopathology 2018; 40(6):e90.
American Journal of Dermatopathology
A 79 year-old male with a history of non-melanoma skin cancer and sundamaged skin presented for a follow up skin check. On examination, anecchymotic nodule was identified on his left frontal scalp, which was notpresent in a clinical photograph taken exactly 2 years prior to the current visit.The patient denied any preceding trauma or associated tenderness. A shavebiopsy revealed mitotically active, atypical epithelioid and pleomorphicappearing multinucleated cells dissecting between collagen bundles in thedermis with prominent associated erythrocyte extravasation. A background ofsolar elastosis was also observed. These microscopic findings alone combinedwith the clinical presentation raised concern for angiosarcoma. However,immunohistochemical stains for vascular markers (ERG, CD31, and CD34)failed to highlight the atypical cells. Additional stains were performedincluding S100, HMWK, Desmin, and SMA which were negative. A CD68stain revealed scattered positivity. Taken together, these findings were mostconsistent with the rare variant of atypical fibroxanthoma, known as thepseudoangiomatoid-type. A review of this entity will be presented.