When Benign Peripheral Nerve Sheath Tumors Start to Mix and Match

The term “benign peripheral nerve sheath tumor” comprises a group of tumors with a wide range of presentations, including neurofibroma, schwannoma, nerve sheath myxoma, and perineuroma. Classically, tumors present as one phenotype, allowing precise classification, but recently, hybrid tumors have been described.

The authors of this retrospective study present the clinicopathologic features of benign cutaneous plexiform nerve sheath tumor spanning the perineuroma and cellular neurothekeoma types in nine patients (mean age, 57; slight predominance, male). The clinical presentation was a solitary dome-shaped papule on the lips. Histologically, a well-circumscribed dermal nodule with plexiform growth pattern was noted. Proliferation consisted of…