title: Thyroid incidentalomas on fluorine-18-fluorodeoxyglucose positron emission tomography-computed tomography: incidence, malignancy risk, and comparison of standardized uptake values.
abstract: BACKGROUND
  To determine the incidence of fluorine-18-fluorodeoxyglucose (FDG) avid thyroid incidentalomas detected on positron emission tomography (PET) with integrated computed tomography (CT), and correlate the FDG-PET-CT findings to cytology.
  
  
  METHODS
  A total of 942 FDG-PET-CT reports were retrospectively reviewed. Patients with FDG-avid thyroid incidentalomas were further reviewed for correlative cytology.
  
  
  RESULTS
  The incidence of FDG-avid thyroid incidentalomas is 2.2%. Thyroid malignancies were identified in 3 of 6 patients who underwent cytologic correlation, with a positive predictive value of 50% (95% confidence interval, 14%-86%). The mean maximum standardized uptake values of benign and malignant FDG-avid thyroid incidentalomas were 5.6 and 6.6, respectively.
  
  
  CONCLUSIONS
  A FDG-avid thyroid incidentaloma may predict underlying malignancy. Cytologic assessment should be considered for FDG-avid thyroid incidentalomas.
authors.affiliation: Department of Nuclear Medicine and PET, Singapore General Hospital, Singapore. kao.yung.hsiang@singhealth.com.sg
authors.forename: Yung H
authors.initials: YH
authors.lastname: Kao
authors.forename: Siew S
authors.initials: SS
authors.lastname: Lim
authors.forename: Seng C
authors.initials: SC
authors.lastname: Ong
authors.forename: Ajit K
authors.initials: AK
authors.lastname: Padhy
mesh_terms: D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D033162:Incidental Findings; D008297:Male; D064847:Multimodal Imaging; D049268:Positron-Emission Tomography; D011237:Predictive Value of Tests; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D018709:Statistics, Nonparametric; D013964:Thyroid Neoplasms / Q000000981:diagnostic imaging* / Q000453:epidemiology; D014057:Tomography, X-Ray Computed
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18