title: Focal nodular hyperplasia: natural course observed with CT and MRI.
abstract: OBJECTIVE
  The purpose of this work was to assess the natural course of biopsy-proven focal nodular hyperplasia (FNH).
  
  
  METHODS
  Eighteen biopsy-proven FNHs in 14 patients (12 women and 2 men) who were followed for at least 6 months with CT and/or MRI were included in the study. The volume of the lesions was calculated twice by two observers using the summation of areas method. Intra- and interobserver variability was assessed by intraclass correlation coefficients. Longitudinal data analysis was performed with generalized estimating equations.
  
  
  RESULTS
  The volume of FNH was stable in 6 cases, decreased in 10 cases, and increased in 2 cases. Intra- and interobserver variability in size measurements was 5-10%. Intraclass correlation coefficients were >0.992. Longitudinal data analysis showed that there was a general trend of lesion regression.
  
  
  CONCLUSIONS
  Long-term follow-up and objective measurements performed in patients with biopsy-proven lesions show that the natural course of FNH is variable. In particular, lesion regression is not rare.
authors.affiliation: Department of Radiology, Université Catholique de Louvain, St. Luc University Hospital, Brussels, Belgium.
authors.forename: I
authors.initials: I
authors.lastname: Leconte
authors.forename: B E
authors.initials: BE
authors.lastname: Van Beers
authors.forename: M
authors.initials: M
authors.lastname: Lacrosse
authors.forename: C
authors.initials: C
authors.lastname: Sempoux
authors.forename: J
authors.initials: J
authors.lastname: Jamart
authors.forename: R
authors.initials: R
authors.lastname: Materne
authors.forename: V
authors.initials: V
authors.lastname: Baudrez
authors.forename: Y
authors.initials: Y
authors.lastname: Horsmans
mesh_terms: D000293:Adolescent; D000328:Adult; D001706:Biopsy; D003937:Diagnosis, Differential; D005260:Female; D020518:Focal Nodular Hyperplasia / Q000175:diagnosis*; D006801:Humans; D008099:Liver / Q000000981:diagnostic imaging / Q000473:pathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed