RET and medullary thyroid gland carcinoma: The most frequently investigated somatic molecular alterations were: (i) BRAF V600E mutation, NTRK fusions and RET fusions in RAI-R DTC; (ii) BRAF V600E mutation, NTRK, ALK and RET fusions in ATC; and (iii) RET mutations in MTC (Fig. 1E).