title: Quantitative dosimetry for yttrium-90 radionuclide therapy: tumor dose predicts fluorodeoxyglucose positron emission tomography response in hepatic metastatic melanoma.
abstract: OBJECTIVE
  To assess a new method for generating patient-specific volumetric dose calculations and analyze the relationship between tumor dose and positron emission tomography (PET) response after radioembolization of hepatic melanoma metastases.
  
  
  METHODS
  Yttrium-90 ((90)Y) bremsstrahlung single photon emission computed tomography (SPECT)/computed tomography (CT) acquired after (90)Y radioembolization was convolved with published (90)Y Monte Carlo estimated dose deposition kernels to create a three-dimensional dose distribution. Dose-volume histograms were calculated for tumor volumes manually defined from magnetic resonance imaging or PET/CT imaging. Tumor response was assessed by absolute reduction in maximum standardized uptake value (SUV(max)) and total lesion glycolysis (TLG).
  
  
  RESULTS
  Seven patients with 30 tumors treated with (90)Y for hepatic metastatic melanoma with available (90)Y SPECT/CT and PET/CT before and after treatment were identified for analysis. The median (range) for minimum, mean, and maximum dose per tumor volume was 16.9 Gy (5.7-43.5 Gy), 28.6 Gy (13.8-65.6 Gy) and 36.6 Gy (20-124 Gy), respectively. Response was assessed by fluorodeoxyglucose PET/CT at a median time after treatment of 2.8 months (range, 1.2-7.9 months). Mean tumor dose (P = .03) and the percentage of tumor volume receiving ≥ 50 Gy (P < .01) significantly predicted for decrease in tumor SUV(max), whereas maximum tumor dose predicted for decrease in tumor TLG (P < .01).
  
  
  CONCLUSIONS
  Volumetric dose calculations showed a statistically significant association with metabolic tumor response. The significant dose-response relationship points to the clinical utility of patient-specific absorbed dose calculations for radionuclide therapy.
authors.affiliation: Department of Radiation Oncology, Emory University, 1365 Clifton Road NE, Suite CT 104, Atlanta, GA 30322; Winship Cancer Institute, Emory University, 1365 Clifton Road NE, Suite CT 104, Atlanta, GA 30322. Electronic address: brupper@emory.edu.
authors.forename: Bree R
authors.initials: BR
authors.lastname: Eaton
authors.affiliation: Department of Radiology and Imaging Sciences, Divisions of Interventional Radiology and Image Guided Medicine, Emory University, 1365 Clifton Road NE, Suite CT 104, Atlanta, GA 30322; Winship Cancer Institute, Emory University, 1365 Clifton Road NE, Suite CT 104, Atlanta, GA 30322.
authors.forename: Hyun S
authors.initials: HS
authors.lastname: Kim
authors.affiliation: Department of Radiation Oncology, Emory University, 1365 Clifton Road NE, Suite CT 104, Atlanta, GA 30322; Winship Cancer Institute, Emory University, 1365 Clifton Road NE, Suite CT 104, Atlanta, GA 30322.
authors.forename: Eduard
authors.initials: E
authors.lastname: Schreibmann
authors.affiliation: Divisions of Nuclear Medicine and Molecular Imaging, Emory University, 1365 Clifton Road NE, Suite CT 104, Atlanta, GA 30322; Winship Cancer Institute, Emory University, 1365 Clifton Road NE, Suite CT 104, Atlanta, GA 30322.
authors.forename: David M
authors.initials: DM
authors.lastname: Schuster
authors.affiliation: Divisions of Nuclear Medicine and Molecular Imaging, Emory University, 1365 Clifton Road NE, Suite CT 104, Atlanta, GA 30322.
authors.forename: James R
authors.initials: JR
authors.lastname: Galt
authors.affiliation: Divisions of Nuclear Medicine and Molecular Imaging, Emory University, 1365 Clifton Road NE, Suite CT 104, Atlanta, GA 30322; Winship Cancer Institute, Emory University, 1365 Clifton Road NE, Suite CT 104, Atlanta, GA 30322.
authors.forename: Bruce
authors.initials: B
authors.lastname: Barron
authors.affiliation: Departments of Biostatistics and Bioinformatics, Emory University, 1365 Clifton Road NE, Suite CT 104, Atlanta, GA 30322; Winship Cancer Institute, Emory University, 1365 Clifton Road NE, Suite CT 104, Atlanta, GA 30322.
authors.forename: Sungjin
authors.initials: S
authors.lastname: Kim
authors.affiliation: Departments of Biostatistics and Bioinformatics, Emory University, 1365 Clifton Road NE, Suite CT 104, Atlanta, GA 30322; Winship Cancer Institute, Emory University, 1365 Clifton Road NE, Suite CT 104, Atlanta, GA 30322.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Department of Radiation Oncology, Emory University, 1365 Clifton Road NE, Suite CT 104, Atlanta, GA 30322; Winship Cancer Institute, Emory University, 1365 Clifton Road NE, Suite CT 104, Atlanta, GA 30322.
authors.forename: Jerome
authors.initials: J
authors.lastname: Landry
authors.affiliation: Department of Radiation Oncology, Emory University, 1365 Clifton Road NE, Suite CT 104, Atlanta, GA 30322; Winship Cancer Institute, Emory University, 1365 Clifton Road NE, Suite CT 104, Atlanta, GA 30322.
authors.forename: Tim
authors.initials: T
authors.lastname: Fox
mesh_terms: D000328:Adult; D000368:Aged; D004621:Embolization, Therapeutic / Q000379:methods*; D019788:Fluorodeoxyglucose F18; D006019:Glycolysis; D006801:Humans; D008113:Liver Neoplasms / Q000000981:diagnostic imaging / Q000378:metabolism / Q000532:radiotherapy* / Q000556:secondary; D008279:Magnetic Resonance Imaging; D008545:Melanoma / Q000000981:diagnostic imaging / Q000378:metabolism / Q000532:radiotherapy* / Q000556:secondary; D008875:Middle Aged; D009010:Monte Carlo Method; D064847:Multimodal Imaging; D049268:Positron-Emission Tomography; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011829:Radiation Dosage; D019275:Radiopharmaceuticals / Q000008:administration & dosage*; D013997:Time Factors; D015899:Tomography, Emission-Computed, Single-Photon; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D015021:Yttrium Radioisotopes / Q000008:administration & dosage*
chemical_list: D019275:Radiopharmaceuticals; D015021:Yttrium Radioisotopes; D019788:Fluorodeoxyglucose F18
keywords: (90)Y; (99m)Tc-MAA; CC; DVH; EORTC; European Organization for Research and Treatment of Cancer; HCC; PMR; SD; SUV(max); TLG; V; correlation coefficient; dose-volume histogram; hepatocellular carcinoma; maximum standardized uptake value; partial metabolic response; standard deviation; technetium-99m-macroaggregated albumin; total lesion glycolysis; volume (eg, V10); yttrium-90