Optimal Threshold of Stimulated Serum Thyroglobulin Level for 18F-FDG PET/CT imaging in Patients with Thyroid Cancer / 华中科技大学学报（医学）（英德文版）

ABSTRACT

This study was to explore the optimal threshold of thyroid-stimulating hormone (TSH)-stimulated serum thyroglobulin (s-Tg) for patients who were to receive 18F-fluorodeoxyglucose (18F-FDG) PET/CT scan owing to clinical suspicion of differentiated thyroid cancer (DTC) recurrence but negative post-therapeutic 131I whole-body scan (131I-WBS).A total of 60 qualified patients underwent PET/CT scanning from October 2010 to July 2014.The receiver operating characteristic (ROC) curve analyses showed that s-Tg levels over 49 μg/L led to the highest diagnostic accuracy of PET/CT to detect recurrence,with a sensitivity of 89.5％ and a specificity of 90.9％.Besides,bivariate correlation analysis showed positive correlation between s-Tg levels and the maximum standardized uptake values (SUVmax) of 18F-FDG in patients with positive PET/CT scanning,suggesting a significant influence of TSH both on Tg release and uptake of 18F-FDG.So,positive PET/CT imaging is expected when patients have negative 131I-WBS but s-Tg levels over 49 μg/L.