Positron emission tomography with 2-deoxy-2-[18F]fluoro-d -glucose in patients with thyroid diseases : FDG PET in thyroid diseases

Abstract

The aim of this thesis was to contribute to the field of positron emission tomography (PET) with 2-deoxy-2-[18F]fluoro-D-glucose (FDG) in benign and malignant diseases of the thyroid gland. The primary method used was review of retrospectively or prospectively enrolled patients referred for FDG PET at the Mayo Clinic, Rochester, MN, USA. PET findings were compared with the results of all other imaging, laboratory results and clinical information, as well as, extensive recording of follow-up information for up to 92 months. We found that an incidental finding of diffusely increased FDG uptake in the thyroid gland was associated with chronic autoimmune thyroiditis. Regardless of the intensity of the FDG-uptake (SUV), an incidental finding of a focally increased FDG uptake in the thyroid gland represented a malignant tumor in about 1/3 of the patients. We found that FDG PET had a high prognostic value in patients with different forms of thyroid cancer. Furthermore, our findings indicate that FDG PET may improve disease detection and have an important impact on the management of patients with aggressive thyroid cancer.