Incidental (Malignancy) and Coincidental (Idiopathic Polydactylous Longitudinal Erythronychia) Conditions in Patients With Segmental Neurofibromatosis

Segmental neurofibromatosis (SNF) is an uncommon presentation of neurofibromatosis type 1 (NF-1). Although patients with SNF are at a lower risk for developing NF-1–associated complications, the estimated occurrence of related malignancies may be approaching the frequency observed in patients with NF-1. Idiopathic polydactylous longitudinal erythronychia also may be associated with SNF, though the frequency of this association remains to be determined.