SLC1A5 and neoplasm: For the anti-1-amino-3-[F-18]-fluorocyclobutane-1-carboxylic acid, anti-3-[F-18] FACBC, [18F]fluciclovine, transport is mediated primarily by the neutral amino acid novel alanine serine cysteine transporters 2 (ASCT2), and to a lesser extent LAT-1, and has been demonstrated to have significantly higher image contrast (tumor-to-background) compared to methyl-[11C]-methionine ([11C]MET), owing to a limited penetration in the healthy brain [21].