title: Catecholamines influence myocardial 123I MIBG uptake in neuroblastoma patients.
abstract: OBJECTIVE
  Cardiac 123I metaiodobenzylguanidine (MIBG) imaging can be influenced by several factors. We evaluated the relationship between catecholamine measurements and cardiac 123I MIBG uptake in neuroblastoma patients.
  
  
  METHODS
  30 neuroblastoma patients were retrospectively assessed on cardiac 123I MIBG uptake and urinary catecholamine dopamine and metabolites, homovanillic acid (HVA) and vanillylmandelic acid (VMA). Cardiac 123I MIBG uptake was quantified by heart-to-mediastinum (H/M) ratios, which were calculated into standard deviation scores (SDS) using age-specific reference values.
  
  
  RESULTS
  In 17 (57%) and 12 patients (40%) H/M ratio measurements were below -1.0 and -2.0 SDS at diagnosis. A significant inverse correlation between the average of urine metabolites HVA and VMA, and H/M ratio SDS was observed (r -.39, p = 0.04). Furthermore, there was a significant correlation between the urinary catecholamine metabolite HVA and H/M ratio SDS (r -.40, p=0.04).
  
  
  CONCLUSIONS
  Routine calculation of H/M ratios in 123I MIBG scintigrams of neuroblastoma patients is not helpful because it will not identify cardiac ventricular dysfunction in this patient category. A low H/M ratio on 123I MIBG scintigraphy is explained by increased cathecholamine levels secreted by neuroblastoma tumours.
authors.forename: R L F
authors.initials: RL
authors.lastname: van der Palen
authors.affiliation: Ben F. Bulten, Department of Nuclear Medicine, Radboud University Nijmegen Medical Centre (internal postal code 756), P.O. Box 9101, 6500 HB Nijmegen, The Netherlands, Tel. +31/243 61 40 48, Fax +31/243 61 89 42, E-mail: B.Bulten@nucmed.umcn.nl.
authors.forename: B F
authors.initials: BF
authors.lastname: Bulten
authors.forename: A M C
authors.initials: AM
authors.lastname: Mavinkurve-Groothuis
authors.forename: L
authors.initials: L
authors.lastname: Bellersen
authors.forename: H W M
authors.initials: HW
authors.lastname: van Laarhoven
authors.forename: L
authors.initials: L
authors.lastname: Kapusta
authors.forename: L F
authors.initials: LF
authors.lastname: de Geus-Oei
mesh_terms: D019797:3-Iodobenzylguanidine / Q000493:pharmacokinetics*; D000293:Adolescent; D002395:Catecholamines / Q000378:metabolism*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006321:Heart / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D009206:Myocardium / Q000378:metabolism*; D009447:Neuroblastoma / Q000000981:diagnostic imaging* / Q000378:metabolism*; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D002395:Catecholamines; D019275:Radiopharmaceuticals; D019797:3-Iodobenzylguanidine
keywords: Metaiodobenzylguanidine; cardiac imaging; catecholamine; neuroblastoma