title: Vestibular schwannoma growth in patients with neurofibromatosis Type 2: a longitudinal study.
abstract: OBJECTIVE
  The factors that determine the growth rates of vestibular schwannomas (VSs) in patients with neurofibromatosis Type 2 (NF2) are unknown. The authors undertook this study to determine if clinical factors or type of constitutional NF2 mutation were associated with VS growth rates in cases of NF2.
  
  
  METHODS
  The authors reviewed serial gadolinium-enhanced magnetic resonance (MR) images of the head and full spine of 37 patients with sporadic NF2 who had been observed over periods ranging from 0.2 to 8 years (median 3.9 years) at a specialized referral clinic for NF2. A box model was used to calculate VS volumes so that tumor growth rates could be estimated. Temperature-gradient gel electrophoresis was used to screen for constitutional NF2 mutations. The VS growth rates tended to decrease with increasing patient age at onset of signs or symptoms (r2 = 0.23, p = 0.003) and at the time the baseline gadolinium-enhanced MR image was obtained (r2 = 0.38, p < 0.001). The authors did not find significant associations between VS growth rates and the number of non-VS cerebral or spinal tumors or different types of constitutional NF2 mutations.
  
  
  CONCLUSIONS
  There is considerable variability in growth rates of VSs in patients with NF2, but they tend to be higher in patients who are younger at onset of signs or symptoms.
authors.affiliation: Department of Neurology, Klinikum Nord Ochsenzoll, Hamburg, Germany.
authors.forename: Victor-Felix
authors.initials: VF
authors.lastname: Mautner
authors.forename: Michael E
authors.initials: ME
authors.lastname: Baser
authors.forename: Sarang D
authors.initials: SD
authors.lastname: Thakkar
authors.forename: Urs M
authors.initials: UM
authors.lastname: Feigen
authors.forename: J M
authors.initials: JM
authors.lastname: Friedman
authors.forename: Lan
authors.initials: L
authors.lastname: Kluwe
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D001921:Brain / Q000473:pathology / Q000503:physiopathology; D002648:Child; D004252:DNA Mutational Analysis; D005260:Female; D005500:Follow-Up Studies; D005682:Gadolinium; D016515:Genes, Neurofibromatosis 2 / Q000502:physiology; D006801:Humans; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging; D008297:Male; D009154:Mutation / Q000235:genetics*; D016518:Neurofibromatosis 2 / Q000235:genetics / Q000473:pathology* / Q000503:physiopathology*; D009464:Neuroma, Acoustic / Q000235:genetics / Q000473:pathology* / Q000503:physiopathology*; D012720:Severity of Illness Index; D013131:Spine / Q000473:pathology / Q000503:physiopathology; D013997:Time Factors
chemical_list: D005682:Gadolinium