18F-FDG PET/CT in Differential Diagnosis of Incidental Benign or Malignant Thyroid Focal Hypermetabolic Lesions / 中国医学影像学杂志

ABSTRACT

Purpose To investigate the significance of PET/CT in differential diagnosis of incidental thyroid benign or malignant lesions with high fluorodeoxyglucose (FDG) uptake.Materials and Methods Forty cases with focal high FDG uptake lesion in thyroid accidently detected by PET/CT were retrospectively collected. The subjects were dived into physiological uptake group (n=18), benign lesion group (n=16) and malignant lesion group (n=6) according to the pathology or follow-up examinations. The average SUVmax of different groups was analyzed, and ROC curve was used todetect benign or malignant lesions.Results The average SUVmax was 3.7±1.1 in physiological uptake group, 4.9±2.3 in benign lesion group and 9.5±4.8 in malignant lesion group. Significant difference was noticed among the three groups. The average SUVmax in malignant lesion group was higher than that of the other two groups with statistical difference (P0.05). ROC analysis showed that the sensitivity and specificity for thyroid malignant tumor were 100.0% and 87.2% at SUVmax of 8.5.Conclusion18F-FDG PET/CT plays an important role in differentiating benign lesions of thyroid from malignance, but it is not helpful to identify benign lesions from physiologic uptake.