Already after publication of the ATA Guidelines, in 2012 Elisei and co-workers [8] presented a study of 84 RET gene mutation carriers with MEN 2A and FMTC where thyroidectomy was proposed to RET mutation carriers with elevated serum Ct concentrations independently of the age and type of RET mutation status. The gene discussed is RET; the disease is multiple endocrine neoplasia type 2A.