MANAGEMENT PRINCIPLES OF INCIDENTAL THYROID 18F-FDG UPTAKE IDENTIFIED ON 18F-FDG PET/CT IMAGING.

PURPOSE: The purpose of this study is to determine the clinical significance of incidental thyroid 18F-FDG PET/CT uptake in oncology patients with the focus achieving the most appropriate management of this challenging situation.

MATERIALS AND METHOD: Two thousand five hundred and eighty 18F-FDG PET/CT studies performed at our institute in the past 4 years were retrospectively reviewed. Patients with incidental FDG uptake in the thyroid gland were further analysed.

RESULTS

The prevalence of incidental FDG uptake in thyroid gland was 7.6% (129 patients). 26 patients (20.1%) had diffuse 18F-FDG PET/CT uptake, 103 patients (79.1%) had nodular uptake in thyroid gland. All diffuse uptake patients who were further examined diagnosed to be a benign condition. 53 patients in the nodular uptake group were further examined and the final histopathology examinations revealed an 18.8% malignancy rate. SUV max values ranged from 2 to 21.8 with a significant highness in malignant lesions.

CONCLUSION

18F-FDG PET/CT uptake in the thyroid gland may be diffuse or nodular. Diffuse uptake needs no further examination as it usually accompanied by benign thyroid disorders. Patients with nodular uptake whose general condition is good should be further examined due to high rates of malignancy.