Abstract
2020
Objectives: To evaluate the usefulness of dual-time-point (DTP) fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography examinations (18F-FDG PET/CT) studies in differentiation benign lesions from malignancy in the head and neck patients.
Methods: The total of 126 patients (25 women, 101 men, mean age: 57±14 years, range: 20-81 years) underwent sequential biphasic 18F-FDG PET/CT examinations at 60 and 90min post intravenously injection (p.i.) of the 18F-FDG. We evaluated the metabolic activity of 70 malignant lesions within the pharynx, 56 non-malignant findings and 60 normal blood vessels with the maximal and mean standardized uptake value (SUVmax, SUVmean) and the retention index (RI-SUVmax). We used the receiver operating characteristics (ROC) analysis to evaluate the SUVmax value cut-off which might distinguish benign and malignant lesions.
Results: In this material, the SUVmax value at 60 and 90min p.i. of 3.27 (sensitivity/specificity: 97%/83%) and 4.10 (sensitivity/specificity: 92%/92%) suggested the pathologic process regardless the etiology of the abnormality. When compared normal and non-malignant structures within the pharynx the SUVmax value cut-off at 60 and 90min p.i. was 2.07 (sensitivity/specificity: 95%/100%) and 1.98 (sensitivity/specificity: 98%/98%), respectively. The SUVmax on initial and delayed scans of 3.90 (sensitivity/specificity: 88%/82%) and 4.10 (sensitivity/specificity: 92%/84%), respectively, suggested the malignant etiology when compared malignant and non-malignant pharyngeal subsites. The increase of the SUVmax value over time of 3.3% (sensitivity/specificity: 78%/79%) suggested abnormality, while RI-SUVmax of 6.2% indicated malignant etiology (sensitivity/specificity: 96%/32%).
Conclusions: The delayed 18F-FDG PET/CT protocol improves the specificity of the method in the differential diagnosis of the pharynx cancer.