18F-FDG-PET/CT features of primary tumours for predicting the risk of recurrence in thyroid cancer after total thyroidectomy: potential usefulness of combination of the SUV-related, volumetric, and heterogeneous texture parameters

Objective:This retrospective study examined whether the primary tumour 18F-FDG uptake features could predict the high-risk of recurrence in differentiated thyroid cancer (DTC) patients.Methods:The enrolled 114 DTC patients underwent preoperative 18F-FDG-PET/CT. SUVmax, SUVmean, metabolic tumour volume (MTV), total lesion glycolysis (TLG) and 6 texture parameters were obtained. Because the texture features can be confounded by the tumour volume effects, 18F-FDG-avid tumour patients were divided into two groups (tumours with MTV ≤ 10.0 cm3 and >10.0 cm3). Diagnostic performance for predicting the high-risk was evaluated by the area under the curve (AUC) by the ROC curve analysis.Results:Eighty eight 18F-FDG-avid tumours revealed more advanced-risk classification (p = 0.015 → 0.02) than 26 18F-FDG-nonavid tumours, which yielded no high-risk patients. In the 44 MTV > 10.0 cm3 18F-FDG-avid tumour patients, 8 high-risk patients revealed significantly higher SUVmax, SUVmean, MTV, TLG, intensity variability and s...