Compared to 99mTc-labeled PSMA inhibitors such as [99mTc]Tc-MIP-1404, our MJ9 analogues revealed comparable or even higher activity levels in the tumor and noticeably lower levels in the kidneys [10] in tumor-bearing animals at 1 h p.i., which was expected, as the latter organ is PSMA-positive but GRPR-negative. Here, GRPR is linked to neoplasm.