The L-type amino acid transporter 1 (LAT1), which mediates L-[18F]FDOPA uptake, is highly upregulated in numerous NETs including pheochromocytoma, paraganglioma, medullary thyroid carcinoma (MTC), lung NETs and gastrointestinal carcinomas [15-18]. This evidence concerns the gene SLC7A5 and medullary thyroid gland carcinoma.