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Myopericytoma presenting as a painful dark subungual discoloration
Sofia Antunes-Duarte1, Marta Aguado Lobo, Pablo Espinosa Lara
1Dermatology Department, Hospital de Santa Maria, Centro Hospitalar Universitario Lisboa Norte, E.P.E., Lisbon, Portugal.
Abstract:
Myopericytoma is an uncommon benign neoplasm that arises from the perivascular myoid cells. It typically presents as a painless well-circumscribed cutaneous or soft-tissue nodule, most commonly on the extremities of adults. Histologically, it is characterized by spindle-shaped myoid-appearing cells with a concentric arrangement in vessel walls, that are immunoreactive to alpha-smooth muscle actin and often for h-caldesmon, but negative for other smooth muscle markers. Herein, we present an unusual case of a painful subungual myopericytoma presenting as a dark subungual discoloration.
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