title: Variable MR imaging appearances of focal nodular hyperplasia in pediatric cancer patients.
abstract: BACKGROUND
  Focal nodular hyperplasia (FNH) is rare in the general pediatric population but is increasingly found in treated pediatric cancer patients. FNH can be incidentally found on CT and MRI and can be misdiagnosed as liver metastasis in patients with an oncological history.
  
  
  OBJECTIVE
  To describe the MR imaging findings of FNH in pediatric cancer patients.
  
  
  METHODS
  Ten children who had been treated for a primary malignancy and who were diagnosed with FNH from 2003 to 2010 were identified from a search for FNH in our pathology and radiology databases. Patients were included if they were treated for a primary malignancy and had undergone MR imaging of the liver including T1-weighted, T2-weighted and dynamic contrast-enhanced T1-weighted sequences.
  
  
  RESULTS
  FNH from all patients (n=10) demonstrated typical homogeneous arterial enhancement on MRI. The FNH was often multiple and small (7/10 patients), lacking a central scar, with variable imaging characteristics including signal hyperintensity on both T1- and T2-weighted images (4/10 patients), especially in the setting of hepatic hemosiderosis.
  
  
  CONCLUSIONS
  FNH has a variable MR appearance in pediatric cancer patients and should be considered in the differential diagnosis of hypervascular liver lesions.
authors.affiliation: Department of Radiology, Memorial Sloan-Kettering Cancer Center, 1275 York Ave., New York, NY 10065, USA. dok@mskcc.org
authors.forename: Richard K G
authors.initials: RK
authors.lastname: Do
authors.forename: Sara D
authors.initials: SD
authors.lastname: Shaylor
authors.forename: Jinru
authors.initials: J
authors.lastname: Shia
authors.forename: Amy
authors.initials: A
authors.lastname: Wang
authors.forename: Kim
authors.initials: K
authors.lastname: Kramer
authors.forename: Sara J
authors.initials: SJ
authors.lastname: Abramson
authors.forename: Anita P
authors.initials: AP
authors.lastname: Price
authors.forename: Lawrence H
authors.initials: LH
authors.lastname: Schwartz
mesh_terms: D000293:Adolescent; D017668:Age of Onset; D002648:Child; D002675:Child, Preschool; D005260:Female; D020518:Focal Nodular Hyperplasia / Q000150:complications* / Q000175:diagnosis* / Q000000981:diagnostic imaging; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009369:Neoplasms / Q000150:complications* / Q000175:diagnosis* / Q000000981:diagnostic imaging; D011859:Radiography; D012189:Retrospective Studies; D055815:Young Adult