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]. Here, SLC7A5 is linked to digestive system carcinoma.