In conclusion, we have identified a set of genes (EGLN3, EXO1, UBE2T, UBE2C, FOXM1, CENPA, DLL3, CCNA2, SOX2, KIF23, and CDCA5) differently expressed between high-grade and low-grade MTC. This evidence concerns the gene DLL3 and medullary thyroid gland carcinoma.