SLC2A1 and thyroid gland carcinoma: In conclusion, the positive correlations between [18F]FDG uptake and GLUT1, GLUT3, HK2, and MCT4 expression and differential expression of GLUT1, HK2, and MCT4 in [18F]FDG-positive benign thyroid nodules and [18F]FDG-positive thyroid carcinomas as compared to [18F]FDG-negative benign nodules in the current study suggest that these [18F]FDG-positive benign nodules undergo metabolic changes similar to those in thyroid carcinomas.