CALCA and medullary thyroid gland carcinoma: Total thyroidectomy is the only curative treatment followed by active surveillance, including ultrasonography and tumor markers (calcitonin and carcinoembryonic antigen) to detect possible recurrence of MTC (Cabanillas et al. 2016; Maia et al. 2017; Taralli et al. 2020; Treglia et al. 2013) which occurs in about 50% of the patients (Taralli et al. 2020; Treglia et al. 2013).