title: Intrahepatic Activity Distribution in Radioembolization with Yttrium-90-Labeled Resin Microspheres Using the Body Surface Area Method--A Less than Perfect Model.
abstract: OBJECTIVE
  To retrospectively assess the influence of the parameters of the body surface area (BSA) method in hepatic radioembolization using yttrium-90-labeled microspheres on the determination of the prescribed activity.
  
  
  METHODS
  Data from 283 consecutive patients treated with radioembolization (BSA method) were included. For interindividual comparisons, activity concentrations (ACs; MBq/mL) were calculated for each liver. The impact of the BSA method parameters was assessed by analysis of variance and pairwise t test with Bonferroni-Holm correction.
  
  
  RESULTS
  Prescribed activity was 1.01-2.71 GBq, with BSA, liver volume (LV), tumor burden, and the liver-lung shunt reduction factor (LLS RF) being significant contributing factors to the AC (all P < .0001, analysis of variance). BSA and LV correlated only moderately (ρ = 0.46, P < .0001). Compared with base activity defined by the BSA (median = 1.67 GBq; range, 1.20-2.32 GBq), the activity contribution of tumor burden was small (median = 150 MBq; range, 3-800 MBq). Resulting activities were reduced according to LLS RF by 20% in 12.4% and by 40% in 3.5% of patients. AC was significantly (up to 56%) lower in association with larger LV than in small LV (LV < 1,500 mL vs ≥ 2,500 mL, P < .0001).
  
  
  CONCLUSIONS
  In the BSA model, BSA and LV showed only a moderate correlation, resulting in a significantly lower AC in patients with larger livers. Tumor burden percentage contributed little to the prescribed activity because the BSA model did not account for actual LVs and tumor volumes. These inaccuracies may potentially result in underdosage in patients with larger livers, especially if further LLS RF needs to be applied.
authors: Department of Radiology and Nuclear Medicine, University Hospital Magdeburg, Leipziger Strasse 44, Magdeburg 39120, Germany. Electronic address: oliver.grosser@med.ovgu.de.
authors: Oliver S
authors: OS
authors: Grosser
authors: Department of Radiology and Nuclear Medicine, University Hospital Magdeburg, Leipziger Strasse 44, Magdeburg 39120, Germany.
authors: Gerhard
authors: G
authors: Ulrich
authors: Department of Radiology and Nuclear Medicine, University Hospital Magdeburg, Leipziger Strasse 44, Magdeburg 39120, Germany.
authors: Christian
authors: C
authors: Furth
authors: Department of Radiology and Nuclear Medicine, University Hospital Magdeburg, Leipziger Strasse 44, Magdeburg 39120, Germany; 2(nd) Department of Radiology, Medical University of Gdansk, Gdansk, Poland.
authors: Maciej
authors: M
authors: Pech
authors: Department of Radiology and Nuclear Medicine, University Hospital Magdeburg, Leipziger Strasse 44, Magdeburg 39120, Germany.
authors: Jens
authors: J
authors: Ricke
authors: Department of Radiology and Nuclear Medicine, University Hospital Magdeburg, Leipziger Strasse 44, Magdeburg 39120, Germany.
authors: Holger
authors: H
authors: Amthauer
authors: Department of Radiology and Nuclear Medicine, University Hospital Magdeburg, Leipziger Strasse 44, Magdeburg 39120, Germany; Department of Nuclear Medicine, University Hospital Freiburg, Freiburg, Germany.
authors: Juri
authors: J
authors: Ruf
mesh_terms: D001830:Body Surface Area; D001918:Brachytherapy / Q000379:methods; D003198:Computer Simulation; D004853:Epoxy Resins; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000175:diagnosis / Q000503:physiopathology* / Q000532:radiotherapy*; D008297:Male; D008863:Microspheres; D008875:Middle Aged; D008954:Models, Biological; D011874:Radiometry; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods*; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D015021:Yttrium Radioisotopes / Q000032:analysis / Q000627:therapeutic use*
chemical_list: D004853:Epoxy Resins; D015021:Yttrium Radioisotopes