Advances in Functional Imaging of Differentiated Thyroid Cancer

Abstract

The present review provides a description of recent advances in the field of functional imaging that takes advantage of the functional characteristics of thyroid neoplastic cells (such as radioiodine uptake and FDG uptake) and theragnostic approach of differentiated thyroid cancer (DTC). Physical and biological characteristics of available radiopharmaceuticals and their use with state-of-the-art technologies for diagnosis, treatment, and follow-up of DTC patients are depicted. Radioactive iodine is used mostly with a therapeutic intent, while PET/CT with 18F-FDG emerges as a useful tool in the diagnostic management and complements the use of radioactive iodine. Beyond 18F-FDG PET/CT, other tracers including 124I, 18F-TFB and 68Ga-PSMA, and new methods such as PET/MR, might offer new opportunities in selecting patients with DTC for specific imaging modalities or treatments.

Prognostic Value of Hybrid PET/MR Imaging in Patients with Differentiated Thyroid Cancer

“…18 F-FDG PET/CT, which combines the advantages of metabolic and morphologic imaging, allowing for anatomic localization of focal metabolic activity, is an important tool for the evaluation of patients with DTC, mainly in those with elevated Tg and negative WBS, and has a potential role in personalized therapy of DTC [ 6 , 7 , 8 , 9 , 10 ]. However, supplementary imaging modalities are occasionally required.…”

“…It is conceivable that an optimal diagnostic strategy may be crucial to drive tailored therapeutic approaches. One of the most important diagnostic approaches available in the path of DTC patients is 18 F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) [ 6 , 7 , 8 , 9 , 10 ]. The American Thyroid Association (ATA) guidelines [ 4 ] recommend 18 F-FDG PET/CT in high-risk patients with measurable thyroglobulin (Tg) and an absence of 131 I uptake in the whole-body scan (WBS) for both the prognostics and diagnostics of metastatic patients for better management of patients with advanced disease and to evaluate the response to therapy.…”

Prognostic Role of 2-[18F]FDG PET/CT Metabolic Volume Parameters in Patients Affected by Differentiated Thyroid Carcinoma with High Thyroglobulin Level, Negative 131I WBS and Positive 2-[18F]-FDG PET/CT

“…There are several potential advantages of this tool, such as the radiation dose reduction, a better accuracy in the local tumor extent evaluation and an excellent soft-tissue contrast. A direct comparison between 2-[ 18 F]FDG PET/CT and PET/MRI showed a similar accuracy between the two methods [ 31 , 32 ]. Nevertheless, the real usefulness of PET/MRI needs to be clarified with a larger sample of patients.…”

IAEA Contribution to Nanosized Targeted Radiopharmaceuticals for Drug Delivery

“…I-131 shows remarkably high tumor accumulation compared to any other radionuclide for diagnosis or therapy. I-131 is a widely accepted theranostic nuclear medicine agent extensively used to aid diagnosis and treatment especially for pre- and post-therapy scans in differentiated thyroid cancer patients [ 13 ]. This approach provides accurate surveillance of the disease—thus guiding clinicians for the treatment [ 13 ].…”

“…I-131 is a widely accepted theranostic nuclear medicine agent extensively used to aid diagnosis and treatment especially for pre- and post-therapy scans in differentiated thyroid cancer patients [ 13 ]. This approach provides accurate surveillance of the disease—thus guiding clinicians for the treatment [ 13 ]. It is important to recognize that the high and specific uptake of diagnostic/therapeutic I-131 agent in tumors is a rarity because I-131 agents and a vast majority of nuclear medicine agents fail to localize in optimum doses in neo vascular lesions.…”