BRAF and medullary thyroid gland carcinoma: According to the diagnostic criteria of the 2022 WHO classification of thyroid tumors, the nodule in the left lobe was diagnosed as a low-grade MTC and the nodule in the right lobe as classical PTC, presenting with complex branching papillary and follicular structures, enlarged and crowded cells, oval nuclei with pale dust-like chromatin, irregular nuclear membranes, visible nuclear grooves, intranuclear pseudoinclusions, and a BRAF V600E mutation.