2.3.1. [18F]FDOPA

[ 18F]FDOPA is a large neutral amino acid that resembles natural L-dopa, which can be transported by L-type amino acid transporter 1 (LAT1, SLC7A5) and L-type amino acid transporter 2 (LAT2, SLC7A8) [64]. [18F]FDOPA is a satisfactory probe for detecting MTC metastasis, persistence, and residual disease [59]. However, if [18F]FDOPA imaging is negative or unavailable, [18F]FDG should be considered, especially for aggressive MTCs displaying signs of dedifferentiation or rising carcinoma embryonic antigen (CEA) concentration in serum [59,65].
