PMEL and neoplasm with perivascular epithelioid cell differentiation: PEComas are characterized by epithelioid to spindle cells with eosinophilic to clear cytoplasm, an intimate relationship with blood vessels, and demonstrate positive immunostaining for markers of both melanocytic (HMB45, Melan-A, tyrosinase, microphthalmia transcription factor) and myoid (desmin, smooth muscle actin, muscle-specific actin, caldesmon, calponin) differentiation [1].