Only one malignantnodule (the one diagnosed as medullary thyroid carcinoma) was classified as E1.In that particular case, the patient had a high level of calcitonin, as well asanother thyroid nodule, which was classified as Bethesda V. Of the five thyroidnodules characterized as benign by histology, three were classified as E1. This evidence concerns the gene CALCA and thyroid nodule.