title: Correlation of intra-tumor 18F-FDG uptake heterogeneity indices with perfusion CT derived parameters in colorectal cancer.
abstract: METHODS
  Thirty patients with proven colorectal cancer prospectively underwent integrated 18F-FDG PET/DCE-CT to assess the metabolic-flow phenotype. Both CT blood flow parametric maps and PET images were analyzed. Correlations between PET heterogeneity and perfusion CT were assessed by Spearman's rank correlation analysis.
  
  
  RESULTS
  Blood flow visualization provided by DCE-CT images was significantly correlated with 18F-FDG PET metabolically active tumor volume as well as with uptake heterogeneity for patients with stage III/IV tumors (|ρ|:0.66 to 0.78; p-value<0.02).
  
  
  CONCLUSIONS
  The positive correlation found with tumor blood flow indicates that intra-tumor heterogeneity of 18F-FDG PET accumulation reflects to some extent tracer distribution and consequently indicates that 18F-FDG PET intra-tumor heterogeneity may be associated with physiological processes such as tumor vascularization.
authors.affiliation: INSERM, UMR1101, LaTIM, CHRU Morvan, Brest, France.
authors.forename: Florent
authors.initials: F
authors.lastname: Tixier
authors.affiliation: Institute of Nuclear Medicine, UCL, Euston Road, London, United Kingdom.
authors.forename: Ashley M
authors.initials: AM
authors.lastname: Groves
authors.affiliation: Division of Imaging Sciences and Biomedical Engineering, Kings College London, St Thomas Hospital, London, United Kingdom.
authors.forename: Vicky
authors.initials: V
authors.lastname: Goh
authors.affiliation: INSERM, UMR1101, LaTIM, CHRU Morvan, Brest, France.
authors.forename: Mathieu
authors.initials: M
authors.lastname: Hatt
authors.affiliation: Epidemiology & Biostatistics, CIC Inserm 1402, CHU Milétrie, Poitiers, France.
authors.forename: Pierre
authors.initials: P
authors.lastname: Ingrand
authors.affiliation: Department of Nuclear Medicine, CHU Miletrie, Poitiers, France.
authors.forename: Catherine Cheze
authors.initials: CC
authors.lastname: Le Rest
authors.affiliation: INSERM, UMR1101, LaTIM, CHRU Morvan, Brest, France.
authors.forename: Dimitris
authors.initials: D
authors.lastname: Visvikis
mesh_terms: D015179:Colorectal Neoplasms / Q000175:diagnosis / Q000473:pathology*; D005260:Female; D019788:Fluorodeoxyglucose F18; D018740:Genetic Heterogeneity; D006801:Humans; D008297:Male; D049268:Positron-Emission Tomography / Q000379:methods; D011446:Prospective Studies; D011856:Radiographic Image Enhancement; D019275:Radiopharmaceuticals; D014057:Tomography, X-Ray Computed / Q000379:methods*; D047368:Tumor Burden
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18