title: Malignant peripheral nerve sheath tumours in neurofibromatosis type 1: MRI supports the diagnosis of malignant plexiform neurofibroma.
abstract: Plexiform neurofibroma (PNF) is a typical feature of neurofibromatosis 1 (NF1). About 10% of patients with NF1 develop malignant peripheral nerve-sheath tumours (MPNST), usually arising from PNF, and this is the major cause of poor survival. A better prognosis can be achieved if the tumours are diagnosed at an early stage. Our objective was to establish MRI criteria for MPNST and to test their usefulness in detecting early malignant change in PNF. MRI was performed on 50 patients with NF1 and nerve-sheath tumours, of whom seven had atypical pain, tumour growth or neurological deficits indicative of malignancy; the other 43 were asymptomatic. On MRI all seven symptomatic patients had inhomogeneous lesions, due to necrosis and haemorrhage and patchy contrast enhancement. In one patient, the multiplicity of confluent tumours with inhomogeneous areas in addition to central lesions did not allow exclusion of malignancy. Only three of the 43 asymptomatic patients had comparable changes; the other 40 patients had tumours being of relatively homogeneous structure on T1- and T2-weighted images before and after contrast enhancement. All three asymptomatic patients with inhomogeneous lesions were shown to have MPNST.
authors.affiliation: Department of Neurology, Klinikum Nord Hamburg, Langenhorner Chaussee 560, 22419 Hamburg, Germany. VRGes@aol.com
authors.forename: V F
authors.initials: VF
authors.lastname: Mautner
authors.forename: R E
authors.initials: RE
authors.lastname: Friedrich
authors.forename: A
authors.initials: A
authors.lastname: von Deimling
authors.forename: C
authors.initials: C
authors.lastname: Hagel
authors.forename: B
authors.initials: B
authors.lastname: Korf
authors.forename: M T
authors.initials: MT
authors.lastname: Knöfel
authors.forename: R
authors.initials: R
authors.lastname: Wenzel
authors.forename: C
authors.initials: C
authors.lastname: Fünsterer
mesh_terms: D000293:Adolescent; D000328:Adult; D003937:Diagnosis, Differential; D005260:Female; D006470:Hemorrhage; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009336:Necrosis; D018317:Nerve Sheath Neoplasms / Q000209:etiology* / Q000473:pathology*; D009456:Neurofibromatosis 1 / Q000150:complications*; D010146:Pain / Q000209:etiology; D012680:Sensitivity and Specificity