Multiple cutaneous plexiform schwannomas. Report of a case and review of the literature with particular reference to the association with types 1 and 2 neurofibromatosis and schwannomatosis.

Plexiform schwannomas are relatively rare, benign peripheral nerve sheath tumors, which usually arise in either the dermis or subcutaneous tissue, although rare cases originate in skeletal muscle or other deep somatic soft tissue sites. These tumors may occur singly or as multiple lesions and may be localized to one anatomic site or diffusely distributed. Rare cases have been associated with "schwannomatosis" as well as type 1 neurofibromatosis (von Recklinghausen's disease). We report an unusual case of multiple cutaneous plexiform schwannomas associated with bilateral acoustic neuromas as well as other intracranial and intraspinal neoplasms. In addition, we examine the relationship between the various forms of cutaneous schwannoma, particularly the plexiform variant, and both types 1 and 2 neurofibromatosis; we also examine several purported cases of schwannomatosis.