Routine Excision, Rare Diagnosis: Solitary Neurofibroma Prompting NF1 Screening in an Adolescent

A solitary plexiform neurofibroma in a 15-year-old girl prompted an unexpected referral for neurofibromatosis type 1 (NF1) evaluation. Initially excised under the impression of a lipoma, the lesion's histopathology revealed neural origin features with strong S100 and CD34 positivity. Dermatologic examination uncovered multiple café-au-lait macules, and subsequent referral to neurology raised clinical suspicion for NF1. This case emphasizes how incidental histological findings in a benign-appearing lesion can serve as the first clinical clue of a genetic disorder, triggering appropriate multidisciplinary evaluation.