Pigmented peripheral nerve sheath tumor of the oral cavity is a rare lesion and may be difficult to distinguish clinically from true melanocytic tumors. We report a case of pigmented peripheral nerve sheath tumor with a high degree of melanocytic differentiation and describe its histologic and ultrastructural features. Immunohistochemistry and polymerase chain reaction findings support the neural crest origin of the tumor. The clinical course of our case indicates that local recurrence may be a significant problem in pigmented peripheral nerve sheath tumor
