The therapy of choice in patients suffering from differentiated thyroid cancer (DTC), subdivided into papillary and follicular thyroid carcinoma, is (near-)total thyroidectomy. This is routinely... Show moreThe therapy of choice in patients suffering from differentiated thyroid cancer (DTC), subdivided into papillary and follicular thyroid carcinoma, is (near-)total thyroidectomy. This is routinely followed by the administration of radioiodine (RaI)-131 (131I) to destroy any remaining benign or malignant thyroid tissue, so-called ablation. This thesis has addressed some important clinical questions, related to the application of conventional (131I) and experimental therapies with radionuclides in DTC. Iodine-131 has been used for many years to ablate thyroid remnants following thyroid surgery, but a single optimal activity has not yet been established. Two protocols are commonly used in the Netherlands: the uptake-related ablation strategy in which relatively low activities of 131I are used and the fixed-dose or tumor-related ablation strategy in which higher ablation activities are used. The main aim of this thesis was to study the short-term and long-term outcome parameters in DTC according to the uptake-related ablation protocol and to compare the success rates of both ablation strategies. Furthermore, we investigated whether there was a relation between ablation failure and pre-ablation 24-hour uptake measurement of 131I (by the so-called stunning effect). By assessing the prevalence of second primary tumors in patients treated for thyroid cancer we wanted to confirm that 131I can be used safely regarding long-term effects. Finally, this thesis focused on 111In-DTPA-octreotide scintigraphy and therapy as an alternative tool in progressive radioiodine non-responsive thyroid cancer. Show less
