Radioiodine in medullary thyroid carcinoma

Curative treatment of medullary thyroid carcinoma (MTC) consists of a total thyroidectomy and central neck dissection with additional lymph node dissection of lateral compartments if required. In about 75% of patients, MTC is sporadic and in 25% the disease is genetically. Radioactive iodine (RAI) therapy in MTC is carried out in some centres based on the assumption that cross-irradiation from thyroid follicular cells may be beneficial. However, no systematic studies on the effect of RAI treatment in MTC have been performed.

Meijjer et al. conducted a retrospective, multicentre study to analyze the effect of RAI treatment on survival in 293 MTC patients. Their study shows that additional RAI treatment did not lead to a significant difference in disease-free survival (DFS) and disease-specific survival (DSS) in patients with clinically apparent and preclinical MTC. Neither the stratification according to hereditary stage nor to tumor localization revealed significant effects of RAI treatment on the primary and secondary endpoints. Subgroup analysis of the dosage of RAI showed no effect on DFS either.

They therefore concluded that there is no significant additional value of radioiodine in the treatment of MTC and endorse the current guidelines that RAI has no place in the treatment of MTC.

Read the full article in Meijjer et al(2013) European Journal of Endocrinology 168 779-786 DOI: 10.1530/EJE-12-0943