title: Plexiform neurofibromas in children with neurofibromatosis type 1: frequency and associated clinical deficits.
abstract: OBJECTIVE
  To define the frequency and clinical features of plexiform neurofibromas (PN) in children with neurofibromatosis type 1.
  
  
  METHODS
  Sixty-five children received whole-body magnetic resonance imaging (MRI) and clinical-neurologic examination. Tumor sizes were calculated volumetrically with the program MedX v3.42. χ(2) test, Fisher exact test, t test, and Spearman rank correlation were used for statistical analysis.
  
  
  RESULTS
  Seventy-three tumors were detected in 37 of these 65 children. The mean volume of the tumors was 145.4 mL or 4.8 mL/kg body weight. Eighteen of the 73 PNs caused clinical deficits in 17 children, and the other 56 PNs in 20 children were asymptomatic. Symptomatic tumors were larger than asymptomatic ones (9.6 vs 3.3 mL/kg body weight; P = .01). However, in certain body regions, for example, the head, small tumors also caused clinical deficits. Ten of 18 children ≥11.5 years (median age of the 37 children with PNs) had symptomatic PNs compared with 7 of 19 who were <11.5 years (P = .25).
  
  
  CONCLUSIONS
  PNs cause clinical deficits in young children. Early detection and regular MRI monitoring help to estimate growth and possible upcoming complications, and are thus beneficial for optimizing treatment and management.
authors.affiliation: Phacomatosis Section, Department of Neurology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany. rosi.nguyen@gmail.com
authors.forename: Rosa
authors.initials: R
authors.lastname: Nguyen
authors.forename: Lan
authors.initials: L
authors.lastname: Kluwe
authors.forename: Carsten
authors.initials: C
authors.lastname: Fuensterer
authors.forename: Michael
authors.initials: M
authors.lastname: Kentsch
authors.forename: Reinhard Edgar
authors.initials: RE
authors.lastname: Friedrich
authors.forename: Victor-Felix
authors.initials: VF
authors.lastname: Mautner
mesh_terms: D000293:Adolescent; D000367:Age Factors; D001835:Body Weight; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008279:Magnetic Resonance Imaging; D008297:Male; D009140:Musculoskeletal Diseases / Q000209:etiology; D018318:Neurofibroma, Plexiform / Q000150:complications / Q000473:pathology*; D009456:Neurofibromatosis 1 / Q000473:pathology*; D010146:Pain / Q000209:etiology; D012021:Reflex, Abnormal; D051598:Whole Body Imaging