18F-DCFPyL (2-(3-{1-carboxy-5-[(6-18F-fluoro-pyridine-3-carbonyl)-amino]-pentyl}-ureido)-pentanedioic acid), a radiotracer based on the glutamate-ureido-lysine motif, has the advantage of the longer 110-min half-life of 18F compared with 68Ga and of ease of regional distribution; it has been used successfully for detection of PSMA-expressing prostate cancer lesions (10–12). Here, FOLH1 is linked to prostate cancer.