NTS and neoplasm: Glycoconjugate 8 displayed excellent NTS1 affinity (Ki = 1 nM) in vitro, high stability in vivo, rapid clearance from blood in vivo, and PET studies in nude mice bearing HT29 tumors demonstrated specific tracer uptake and excellent tumor retention with a tumor-to-blood ratio of 4.4 at 60 min p.i.