Atypical fibroxanthoma/pleomorphic dermal sarcoma of the scalp with aberrant expression of HMB-45: a pitfall in dermatopathology.

We report a case of 89-year-old male, with a history of squamous cell carcinoma removed from the right ear, presented to our department with a recently growing, ulcerated and bleeding 2 cm nodule on the scalp. After surgery the tumor recurred with infiltration to the cranial theca. The final histological diagnosis was "pleomorphic dermal sarcoma" (PDS), which showed an unexpected positivity for HMB45. We present, to the best of our knowledge, the first case of AFX/PDS with an aberrant diffuse expression of HMB45 and an aggressive biological behavior, that leads us to a difficult exclusion diagnosis. PMID: 32760054 [PubMed - in process]
Source: Pathologica - Category: Pathology Tags: Pathologica Source Type: research