title: Does I-131-MIBG underestimate skeletal disease burden in neuroblastoma?
abstract: BACKGROUND
  Controversy persists as to the need for both MIBG and bone scanning in routine evaluation of neuroblastoma.
  
  
  OBJECTIVE
  To compare the efficacy of I-131- metaiodobenzylguanidine (MIBG) scan against that of conventional Tc99m- methylene diphosphonate (MDP) bone scan for the detection of skeletal deposition of neuroblastoma.
  
  
  METHODS
  The study included 57 patients (36 boys, 21 girls: age range 1-14 years) of neuroblastoma who underwent both bone scan with Tc99m-MDP and I-131-MIBG scan within 15 days of each other at presentation and during follow-up.
  
  
  RESULTS
  At presentation 11(19.2%) patients had evidence of skeletal metastases on MDP scan against 7 patients who showed bony secondaries on MIBG scan. Of the 7 patients, with positive MIBG and MDP scans, MDP scan detected 11 sites whereas MIBG scan detected 7 sites. On follow-up study, 3 patients with initial abnormal MDP scan but normal MIBG scan, developed skeletal metastases detectable on MIBG scan, whereas 3 of the 46 patients who had normal MDP and MIBG scan at presentation; developed skeletal metastases detectable on MDP scan. MIBG scan was concordant in 2 of them but was normal in the third patient.
  
  
  CONCLUSIONS
  I-131-MIBG underestimates skeletal disease burden in neuroblastoma. Therefore, Tc99m-MDP bone scan should remain a part of routine assessment of patients with neuroblastoma.
authors.affiliation: Department of Nuclear Medicine, All India Institute of Medical Sciences, New Delhi, India. danzig@rediffmail.com
authors.forename: S
authors.initials: S
authors.lastname: Barai
authors.forename: G P
authors.initials: GP
authors.lastname: Bandopadhayaya
authors.forename: A
authors.initials: A
authors.lastname: Malhotra
authors.forename: S
authors.initials: S
authors.lastname: Agarwal
authors.forename: R
authors.initials: R
authors.lastname: Kumar
authors.forename: H
authors.initials: H
authors.lastname: Dhanapathi
mesh_terms: D019797:3-Iodobenzylguanidine; D000293:Adolescent; D001859:Bone Neoplasms / Q000000981:diagnostic imaging / Q000556:secondary*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D009447:Neuroblastoma / Q000000981:diagnostic imaging / Q000556:secondary*; D011446:Prospective Studies; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D013669:Technetium Tc 99m Medronate
chemical_list: D019275:Radiopharmaceuticals; D019797:3-Iodobenzylguanidine; D013669:Technetium Tc 99m Medronate