Clinical comments related to medullary thyroid cancer diagnosis and management

BACKGROUND: The American Thyroid Association (ATA) and more recently the European Thyroid Association (ETA) Guidelines on diagnosis and treatment of medullary thyroid carcinoma (MTC) have provided an excellent tool which was formerly lacking in the field of management of MTC. However, some relevant clinical questions, as the use of somatostatin analogues in the treatment of MTC and the management of pregnant patients with MTC, which were recommended in the guidelines, have been lately extensively revised. Moreover the current issue whether GLP-1 (a glucagon-like peptide-1) analogue is associated with MTC has only superficially been analyzed. METHODS: Publications have been retrieved in MEDLINE at Pubmed (there is no fix date retrospectively) up to October 2012 using the terms “medullary thyroid carcinoma”, “somatostatin”, “pregnancy” and “incretins”. The recommendations made by ATA and ETA were considered. CONCLUSIONS: There are no data supporting the application of somatostatin analogues in the treatment of MTC, while thyroid cancer during or after pregnancy has no impact on the prognosis of disease or on the outcome of pregnancy. However, women with MEN 2 should be carefully controlled before any planned or during any unplanned pregnancy. In contrast to animal studies, there are no consistent human data supporting a stimulatory effect of GLP-1 receptor activation by liraglutide, an incretin mimetic, on calcitonin levels, though establishment of a registry and further studies are required to exclude any association between GLP-1 analogue and MTC.