title: Quantitation of Cancer Treatment Response by18F-FDG PET/CT: Multicenter Assessment of Measurement Variability.
abstract: The aim of this study was to assess the interobserver variability of quantitative18F-FDG PET/CT parameters used in assessments of treatment response across multiple sites and readers.Methods:Paired pre- and posttreatment18F-FDG PET/CT images of 30 oncologic patients were distributed to 22 readers across 15 U.S. and international sites. One reader was aware of the full medical history (readreference) of the patients, whereas the 21 other readers were unaware. The readers selected the single hottest tumor from each study, and made SUV measurements from this target lesion and the liver. Descriptive statistics, percentage changes in the measurements, and their agreements were obtained.Results:The intraclass correlation coefficient for the percentage change in SUVmax(%ΔSUVmax) of the hottest tumor was 0.894 (95% confidence interval [CI], 0.813-0.941), and the individual equivalence coefficient was 1.931 (95% CI, 0.568-6.449) when all reads were included (n= 638). When only the measurements that selected the same target tumor as the readreference(n= 486) were included, the intraclass correlation coefficient for the %ΔSUVmaxwas 0.944 (95% CI, 0.841-0.989), and the individual equivalence coefficient was -0.688 (95% CI, -1.810 to -0.092). The absolute change in SUVmeanof liver corrected for lean body mass showed upper and lower limits of agreement (average bias ± 2 SDs) of 0.13 and -0.13 g/mL.Conclusion:The quantitative tumor SUV changes measured across multiple sites and readers show a high correlation. Selection of the same tumor target among readers further increased the degree of correlation.
authors.affiliation: Division of Nuclear Medicine, The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland.|Department of Radiology, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea.
authors.forename: Joo Hyun
authors.initials: JH
authors.lastname: O
authors.affiliation: Department of Radiology, Harvard Medical School, Dana-Farber Cancer Institute, Boston, Massachusetts.
authors.forename: Heather
authors.initials: H
authors.lastname: Jacene
authors.affiliation: Division of Biostatistics and Bioinformatics, Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland; and.
authors.forename: Brandon
authors.initials: B
authors.lastname: Luber
authors.affiliation: Division of Biostatistics and Bioinformatics, Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland; and.
authors.forename: Hao
authors.initials: H
authors.lastname: Wang
authors.affiliation: Division of Biostatistics and Bioinformatics, Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland; and.
authors.forename: Minh-Huy
authors.initials: MH
authors.lastname: Huynh
authors.affiliation: Division of Nuclear Medicine, The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland.
authors.forename: Jeffrey P
authors.initials: JP
authors.lastname: Leal
authors.affiliation: Division of Nuclear Medicine, The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland wahlr@mir.wustl.edu.|Mallinckrodt Institute of Radiology, Washington University, St. Louis, Missouri.
authors.forename: Richard L
authors.initials: RL
authors.lastname: Wahl
mesh_terms: D001692:Biological Transport; D019788:Fluorodeoxyglucose F18 / Q000378:metabolism; D006801:Humans; D007091:Image Processing, Computer-Assisted; D009369:Neoplasms / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000628:therapy*; D000072078:Positron Emission Tomography Computed Tomography; D016896:Treatment Outcome
chemical_list: D019788:Fluorodeoxyglucose F18
keywords: FDG PET/CT; quantification; response assessment