CCK and medullary thyroid gland carcinoma: In another example, [111In]In-DOTA-MG11, [111In]In-DOTA-CCK (CCK, DAsp-Tyr-Nle-Gly-Trp-Nle-Asp-Phe-NH2) and [99mTc]Tc-Demogastrin 2 ([99mTc]Tc-DG2; DG2, [N4-Gly]MG0; Figure 9) were tested in a head-to-head comparison in six metastatic MTC patients for tumor visualization, renal uptake and metabolic stability [139].