Thyroid pathologies in nuclear medicine

The presented work describes the thyroid pathologies and the nuclear-medical diagnostic approach, in order to obtain a differential diagnosis and the monitoring of various neoplasms; specifically, it describes the importance of radiometabolic treatment with iodine 131, after thyroidectomy surgery. Through a study conducted in patients suffering from thyroid disease, undergoing metabolic radiotherapy, it is shown that, with equal distribution of radioiodine, uptake with at least 3700 MBq of therapeutic dose is obtained. All this can be seen through the whole body scintigraphic framework, obtained through the use of the double-headed gamma camera with collimators for high emission energies. Radiometabolic treatment is effective in patients with a high risk of relapse, while radioiodine treatment is not recommended in low-risk patients.

Overview of Radiolabeled Somatostatin Analogs for Cancer Imaging and Therapy

Identified in 1973, somatostatin (SST) is a cyclic hormone peptide with a short biological half-life. Somatostatin receptors (SSTRs) are widely expressed in the whole body, with five subtypes described. The interaction between SST and its receptors leads to the internalization of the ligand–receptor complex and triggers different cellular signaling pathways. Interestingly, the expression of SSTRs is significantly enhanced in many solid tumors, especially gastro-entero-pancreatic neuroendocrine tumors (GEP-NET). Thus, somatostatin analogs (SSAs) have been developed to improve the stability of the endogenous ligand and so extend its half-life. Radiolabeled analogs have been developed with several radioelements such as indium-111, technetium-99 m, and recently gallium-68, fluorine-18, and copper-64, to visualize the distribution of receptor overexpression in tumors. Internal metabolic radiotherapy is also used as a therapeutic strategy (e.g., using yttrium-90, lutetium-177, and actinium-225). With some radiopharmaceuticals now used in clinical practice, somatostatin analogs developed for imaging and therapy are an example of the concept of personalized medicine with a theranostic approach. Here, we review the development of these analogs, from the well-established and authorized ones to the most recently developed radiotracers, which have better pharmacokinetic properties and demonstrate increased efficacy and safety, as well as the search for new clinical indications.

-SSS/Lipiodol: Development of a Potential Treatment for HCC from Bench to Bedside

Hepatocellular carcinoma (HCC) is the 5th most common tumour worldwide and has a dark prognosis. For nonoperable cases, metabolic radiotherapy with Lipiodol labelled with β-emitters is a promising therapeutic option. The Comprehensive Cancer Centre Eugène Marquis and the National Graduate School of Chemistry of Rennes (ENSCR) have jointly developed a stable and efficient labelling of Lipiodol with rhenium-188 ( MeV) for the treatment of HCC. The major “milestones” of this development, from the first syntheses to the recent first injection in man, are described.