In A431-CCK2R xenografts, [111In]In-DOTA-MGS5 showed a tumour uptake of ~ 24% IA/g which was ~ two fold higher compared to [111In]In-DOTA-[(N-Me)Nle6]MG11 and ~ 20-fold higher compared to [111In]In-DOTA-[1Nal8]MG11 with single substitution, respectively. Here, CCKBR is linked to neoplasm.