title: Dual-time-point [18F]-FDG PET/CT in the diagnostic evaluation of suspicious breast lesions.
abstract: OBJECTIVE
  The authors sought to evaluate whether the reacquisition of images 3 h after administration of radiotracer improves the sensitivity of fluorine-18 fluorodeoxyglucose positron emission tomography computed tomography ([(18)F]-FDG PET/CT) in patients with suspicious breast lesions.
  
  
  METHODS
  Forty-eight patients with 59 breast lesions underwent an [(18)F]-FDG PET/CT study in the prone position with a dual-time-point acquisition performed in the early phase 1 h after FDG administration (PET-1) and in the delayed phase 3 h after FDG administration (PET-2). Both examinations were evaluated qualitatively and semiquantitatively with calculation of the mean percentage variation of the standard uptake values (Delta% SUV(max)) between PET-1 and PET-2. All lesions with an SUV(max) >or=2.5 at PET-1 or a reduction in SUV between PET-1 and PET-2 were considered benign. The definitive histopathological diagnosis was available for all patients included in the study.
  
  
  RESULTS
  The dual-time-point acquisition of [(18)F]-FDG PET/CT displayed an accuracy of 85% for lesions with an SUV(max) >or=2.5 and/or positive Delta% SUV(max), with sensitivity and specificity values of 81% and 100% compared with 69%, 63% (both p<0.001) and 100% (p=n.s.), respectively, for the single-time-point acquisition. Malignant lesions showed an increase in FDG uptake between PET-1 and PET-2, with a Delta% SUV(max) of 10+/-7 (p<0.04). In contrast, benign lesions showed a decrease in SUV between PET-1 and PET-2, with a Delta% SUV(max) of -21+/-7 (p<0.001).
  
  
  CONCLUSIONS
  The delayed repeat acquisition of PET images improves the accuracy of [(18)F]-FDG PET/CT in patients with suspicious breast lesions with respect to the single-time-point acquisition. In addition, malignant breast lesions displayed an increase in FDG uptake over time, whereas benign lesions showed a reduction. These variations in FDG uptake between PET-1 and PET-2 are a reliable parameter that can be used for differentiating between benign and malignant breast lesions.
authors.affiliation: Fondazione S. D. N., Istituto di Ricerca Diagnostica e Nucleare, Via Pansini 5, 80131, Napoli, Italy.
authors.forename: M G
authors.initials: MG
authors.lastname: Caprio
authors.forename: A
authors.initials: A
authors.lastname: Cangiano
authors.forename: M
authors.initials: M
authors.lastname: Imbriaco
authors.forename: F
authors.initials: F
authors.lastname: Soscia
authors.forename: G
authors.initials: G
authors.lastname: Di Martino
authors.forename: A
authors.initials: A
authors.lastname: Farina
authors.forename: G
authors.initials: G
authors.lastname: Avitabile
authors.forename: L
authors.initials: L
authors.lastname: Pace
authors.forename: P
authors.initials: P
authors.lastname: Forestieri
authors.forename: M
authors.initials: M
authors.lastname: Salvatore
mesh_terms: D001943:Breast Neoplasms / Q000000981:diagnostic imaging*; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D008327:Mammography; D008875:Middle Aged; D049268:Positron-Emission Tomography / Q000379:methods*; D019275:Radiopharmaceuticals; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18