Neurofibromatosis I
Neurofibromatosis I Updated: 03/29/2020 © Jun Wang, MD, PhD General features Also called von Recklinghausen disease, NF1 Either autosomal dominant or de novo mutation 5 - 13% develop malignant peripheral nerve sheath tumor 2 - 4 x increased risk of other tumors (childhood CML , ganglioneuroma, meningioma, pheochromocytoma, rhabdomyosarcoma ); acoustic neuroma (schwannoma) , astrocytoma, gastric carcinoid, GIST , glomus tumor , lipoma , optic nerve glioma, Wilm tumor Clinical presentations Multiple neurofibromas (plexiform, solitary) Plexiform neurofibromas relatively specific 6 or more cafe au lait spots over nerve trunks Lisch nodules (pigmented iris hamartomas, majority by age 6) Pathogenesis Neurofibromin defect Resulted in ineffective conversion of RAS to inactive form Genetic abnormality Mutation of NF1 (neurofibromin) at chromosome 17q11.2 Back to soft tissue tumors Back to syndromes Back to contents