An evolving supraclavicular plaque: diagnostic challenges in dermatofibrosarcoma protuberans with atrophic and myxoid features

Dermatofibrosarcoma protuberans is an uncommon locally aggressive mesenchymal neoplasm that classically presents with a proliferation of monomorphic spindled cells with thin nuclei and scant cytoplasm. We report a man in his twenties who presented for an unrelated skin concern and was incidentally noted to have a large, atrophic scar-like depression of the left supraclavicular neck and shoulder. The plaque was photographed and the patient was instructed to follow-up in one year, and careful photo comparison revealed the lesion had subtly enlarged and darkened in color. Accordingly, a punch biopsy revealed features of myxoid dermatofibrosarcoma protuberans, a dermal proliferation of spindled cells with mucinous degeneration and more cellular areas with extensive nuclear palisading resembling the Verocay bodies of a neurofibroma. Clinicians should be aware of the broad clinicopathologic spectrum of DFSP to ensure timely diagnosis and effective treatment. Myxoid dermatofibrosarcoma protuberans is a rare and clinically challenging diagnosis, as the mucinous areas can impart a bluish hue. Dermatofibrosarcoma protuberans can also be atrophic, with the loss of the normal dermal thickness corresponding to a clinical appearance easily mistaken for anetoderma or atrophic scar. Palisaded nuclei resembling the Verocay bodies of schwannoma are sometimes seen and can further obfuscate the diagnosis.