title: Assessment of dual-time-point 18F-FDG-PET imaging for pulmonary lesions.
abstract: OBJECTIVE
  The objective of this study was to assess suitability of dual-time-point 18F-FDG [(18F)-fluoro-2-deoxyglucose]-PET imaging for differentiating between malignant and benign pulmonary lesions, whose size and maximal standardized uptake values (SUVs) are greater than 10 mm and 2.5, respectively.
  
  
  METHODS
  A total of 38 patients, 27 with malignant lesions (n = 30), and 11 with benign lesions (n = 22), were investigated by performing two static acquisitions started at mean times t = 79 and t = 158 min after the tracer injection. A model analysis involving tissue 18F-FDG uptake and release has been developed and applied.
  
  
  RESULTS
  Malignant lesions showed a SUV increase between the two acquisitions for 27 of 30 lesions, and a SUV decrease or constancy for the other three. Benign lesions showed a SUV increase in 19 of 22 lesions, and a SUV decrease in three (both increase and decrease were observed for multiple benign lesions in two patients).
  
  
  CONCLUSIONS
  It is recommended that dual-time-point 18F-FDG-PET imaging is not indicated to differentiate between malignant and benign pulmonary lesions, whose size and maximal SUV are greater than 10 mm and 2.5, respectively. Furthermore, a model analysis suggests that the variation in SUV observed between early and delayed scans may be explained by different values of the 18F-FDG release/uptake ratio.
authors.affiliation: CHU de Bordeaux, Service de Médecine Nucléaire, Laboratoire de Physiologie Cellulaire Respiratoire, et INSERM, France. elaffon@u-bordeaux2.fr
authors.forename: Eric
authors.initials: E
authors.lastname: Laffon
authors.forename: Henri
authors.initials: H
authors.lastname: de Clermont
authors.forename: Hugues
authors.initials: H
authors.lastname: Begueret
authors.forename: Jean-Marc
authors.initials: JM
authors.lastname: Vernejoux
authors.forename: Matthieu
authors.initials: M
authors.lastname: Thumerel
authors.forename: Roger
authors.initials: R
authors.lastname: Marthan
authors.forename: Dominique
authors.initials: D
authors.lastname: Ducassou
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003937:Diagnosis, Differential; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000378:metabolism; D006801:Humans; D008168:Lung / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000473:pathology*; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000473:pathology; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D049268:Positron-Emission Tomography; D013997:Time Factors
chemical_list: D019788:Fluorodeoxyglucose F18