The differentiation between radiation-induced changes and tumor recurrence is a major pitfall of magnetic resonance imaging, which can be overcome by the use of PET. Although amino-acid PET tracers showed several advantages over F-fluorodeoxyglucose in neurooncology, studies comparing these 2 types of radiopharmaceuticals in previously irradiated brain metastases are lacking. Here, we demonstrated a mismatch between 3,4-dihydroxy-6-[F]-fluoro-L-phenylalanine (F-DOPA) and FDG in the first report of a previously irradiated brain metastasis undergoing a longitudinal evaluation by sequential double tracer PET imaging.