The increased radiolabeled amino acid uptake is not directly correlated to higher protein synthesis of the growing tumor or to blood–brain barrier (BBB) breakdown but rather a measure of increased L-amino acid transporter (LAT) and alanine-serine-cysteine-transporter 2 (ASCT2) expression in tumor vasculature [14]. The gene discussed is SLC1A5; the disease is neoplasm.