Deep Penetrating Nevus in a Combined Nevus

Abstract

A 46-year-old female appeared with a pigmented lesion on her left cheek that was removed by shave biopsy. The provisional clinical diagnosis was hemangioma. Histologic examination revealed round to spindle cells with poorly defined cell borders in the superficial dermis. The cells tended to group in a thèque-like arrangement in some areas, and melanin pigment was found associated with these cells. Nevus giant cells were occasionally seen. The shave biopsy was signed out as an intradermal nevus. A wider and deeper excision was performed for esthetic purposes, and the histopathology revealed sheets of round to spindle epithelioid cells surrounding adnexal structures and penetrating through the entire thickness of the dermis and into the subcutaneous fat. A vague nestlike growth pattern of these epithelioid cells was seen in some areas, and numerous large melanin-containing cells were identified. Nuclear pseudoinclusions were seen in many of these epithelioid cells. Mitotic figures were rare and no inflammation was seen. A diagnosis of deep-penetrating nevus was rendered. The differential diagnosis and current knowledge on combined nevi will be discussed.