title: Role of nuclear medicine in the diagnosis and therapy of medullary thyroid carcinoma.
abstract: Medullary thyroid carcinoma (MTC) originates in the parafollicular cells (C cells) of the thyroid, secreting both calcitonin and CEA. Genetic and biochemical testing allow early pre-clinical identification of familial forms. Sporadic MTC usually presents as a solitary palpable thyroid nodule and in most cases the definitive diagnosis is established only at the time of surgery. Nuclear medicine procedures, which play a minor role in the preoperative evaluation of MTC, are essential in postoperative follow-up to detect residual and/or recurrent tumor. A number of radiopharmaceuticals are able to visualize MTC lesions with considerable advantages in diagnosis and prognosis, some of them having also a therapeutic role. Among them, 99mTc[V]DMSA shows the highest diagnostic sensitivity and is considered by many authors the radiopharmaceutical of choice in the postoperative work-up of MTC. Radioiodinated MIBG, in spite of its high specificity has a poor sensitivity (30%); however it is useful for the identification of pheochromocytoma and, in patients showing MIBG uptake in tumoral lesions, high activities of 131I-MIBG may be used for therapy. 111In labeled octreotide detects lesions which express somatostatin receptors; a positive scintigraphic result seems to give also prognostic information (higher uptake in slow-growing lesions) and provides the basis for treatment with octreotide or lanreotide and 111In or 90Y-labeled octreotide analogues. Interesting perspectives are offered by 18F-FDG PET and monoclonal anti-CEA labeled antibodies; the latter may be also used for therapy.
authors.affiliation: Istituto di Medicina Nucleare, Università Cattolica del S. Cuore, Policlinico A. Gemelli, Roma.
authors.forename: V
authors.initials: V
authors.lastname: Rufini
authors.forename: M
authors.initials: M
authors.lastname: Salvatori
authors.forename: M C
authors.initials: MC
authors.lastname: Garganese
authors.forename: D
authors.initials: D
authors.lastname: Di Giuda
authors.forename: M
authors.initials: M
authors.lastname: Lodovica Maussier
authors.forename: L
authors.initials: L
authors.lastname: Troncone
mesh_terms: D002277:Carcinoma / Q000000981:diagnostic imaging* / Q000532:radiotherapy*; D006801:Humans; D019275:Radiopharmaceuticals / Q000627:therapeutic use*; D012680:Sensitivity and Specificity; D013964:Thyroid Neoplasms / Q000000981:diagnostic imaging* / Q000532:radiotherapy*; D014055:Tomography, Emission-Computed
chemical_list: D019275:Radiopharmaceuticals