title: Limited diagnostic and predictive values of dual-time-point 18F FDG PET/CT for differentiation of incidentally detected thyroid nodules.
abstract: OBJECTIVE
  To assess usefulness of dual-time-point (18)F FDG PET/CT to differentiate malignant from benign thyroid nodules and predict the potential factor for malignancy.
  
  
  METHODS
  Fifty patients (age 38-83 years, mean 58 ± 10.6 years) with thyroid nodule were recruited. The (18)F FDG PET/CT images were analyzed visually and quantitatively.
  
  
  RESULTS
  The optimal visual grade of early and delayed images was >grade 3. When SUV(max1) of >2.9 was used as cut off point, the sensitivity and specificity were 55.5 and 63.4%. When SUV(max2) was >3.1, the sensitivity and specificity were 88.8 and 43.9%. When %ΔSUV(max) was ≤9.09%, the sensitivity and specificity were 33.3 and 87.8%. ROC analyses showed that all indices had similar efficacy without significances. No definite predictor could be found for malignant nodules.
  
  
  CONCLUSIONS
  The dual-time-point (18)F FDG PET/CT is not a useful method for differentiating malignant and benign nodules.
authors.affiliation: Department of Nuclear Medicine, School of Medicine, Pusan National University, Busan, 602-739, Republic of Korea. growthkim@daum.net
authors.forename: Seong-Jang
authors.initials: SJ
authors.lastname: Kim
authors.forename: Bo Hyun
authors.initials: BH
authors.lastname: Kim
authors.forename: Yun Kyung
authors.initials: YK
authors.lastname: Jeon
authors.forename: Sang Soo
authors.initials: SS
authors.lastname: Kim
authors.forename: In Joo
authors.initials: IJ
authors.lastname: Kim
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003937:Diagnosis, Differential; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D033162:Incidental Findings; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography; D011237:Predictive Value of Tests; D012372:ROC Curve; D016606:Thyroid Nodule / Q000000981:diagnostic imaging*; D013997:Time Factors; D014057:Tomography, X-Ray Computed
chemical_list: D019788:Fluorodeoxyglucose F18