The complementary role of the two NTS1R and GRPR tumor-situated receptor targets in the tumor uptake of the [99mTc]Tc-DT11+[99mTc]Tc-DB7 mixture could be additionally confirmed by single (NTS1R or GRPR; block 1, 2, respectively; Table 4 and Figure 4) or combined (dual NTS1R/GRPR; block 3; Table 4 and Figure 4) in vivo receptor-blockades during NEP inhibition. Here, GRPR is linked to neoplasm.