Unusual Presentation of Plexiform Neurofibroma Embedded with Large Comedones: A Case Report

Plexiform neurofibromas (PNFs) represent benign neoplasms associated with neurofibromatosis type 1 (NF1), a genetic disorder characterized by mutations in the NF1 gene that lead to dysregulated Ras signaling and uncontrolled cell growth. NF1 manifests with various cutaneous features, including café-au-lait macules and axillary freckling, as well as the development of neurofibromas. PNFs are particularly complex due to their extensive involvement of nerve plexuses and their potential for malignant transformation.

This case report documents a 42-year-old male who presented with numerous neurofibromas, café-au-lait macules, and axillary freckling. Notably, the patient had a large PNF on the right lower back, measuring 10 × 15 cm, which exhibited a "bag of worms" sensation upon palpation. Remarkably, this PNF contained multiple large comedones, each approximately 0.5 × 0.5 cm. Although histopathologic confirmation would have been valuable, a biopsy was not performed because the clinical appearance was clearly consistent with comedones, and the patient strongly refused the procedure due to pain at the lesion site.

This case highlights an unusual presentation of PNF with large comedones, a manifestation not previously reported in the literature. The presence of comedones within a PNF emphasizes the need for thorough clinical evaluation and awareness of atypical manifestations in NF1 patients. This report contributes to the existing knowledge and underscores the importance of recognizing rare dermatological presentations to prevent misdiagnosis and ensure appropriate management.