ABSTRACT
Radionuclide peptide therapy Peptides labelled with a variety of radionuclides for therapeutic applications in neuroendocrine tumours. Most of the peptides have a high affi nity for receptor molecules, which are overexpressed on malignant cells. Somatostatin analogues with a longer half-life are commonly used in the medical management of carcinoid tumours. Somatostatin receptors are found on most tumours with amine precursor uptake and decarboxylation characteristics and neuroendocrine properties, such as carcinoids, paragangliomas, phaeochromocytomas, medullary thyroid cancers, and endocrine pancreatic tumours. Several types of somatostatin analogues such as octreotide, lanreotide, and octreotate are currently available. Octreotide was the fi rst somatostatin analogue to be used after labelling with Indium (111In) and currently radionuclides such as 90Yttrium (90Y) and 177Lutetium (177Lu) are also used. Radiolabelled somatostatin analogue therapy is used in patients with somatostatin receptor-positive neuroendocrine tumours. However, prior documentation of uptake and retention of somatostatin analogue is necessary for treatment. The tracer study is performed prior to the treatment with 111In-octreotide or 68Ga-DOTATOC/DOTA-NOC. Various dose regimes that have been reported are still evolving. Currently, there is no defi nitive protocol available in any of the national guidelines.
