Peripheral nerve sheath tumors associated with neurofibromatosis type 1

Neurofibromatosis type 1 is a hereditary disorder characterized by cutaneous and plexiform neurofibromas. Plexiform neurofibroma is a tumor, involving multiple nerve fascicles, which are surrounded by the perineurium. The tumors look like a bag-of-worms on a cross-section. Syndromic neurofibromas, associated with neurofibromatosis type 1, account for 10% of all neurofibromas. They differ from the sporadic ones by their larger size, increased number, and a 5% risk of malignant transformation. Both types are linked to alterations in the NF1 gene on chromosome 17. This paper illustrates clinical course, diagnosis, surgical management, and morphological features of tumors in neurofibromatosis type 1 in a 21-year-old male who presented with multiple cutaneous lesions and café au lait macules. MRI revealed a subcutaneous neurofibroma in the frontal region. Surgical excision was performed, and histopathological examination confirmed the presence of an atypical neurofibromatous neoplasm of uncertain biologic potential that is specific only to patients with neurofibromatosis type 1. The patient was monitored for timely management of potential complications, including the risk of malignant peripheral nerve sheath tumor development. The World Health Organization introduced this type of tumor in the classification of tumours of the central nervous system in 2021. Keywords: hereditary tumor syndromes, neurofibroma, nerve tumors, premalignant lesions, neuro-oncology