GRPR and neoplasm: Surprisingly, [99mTc]Tc-N4-[Hse7]MJ9 revealed the highest tumor uptake of all compounds at 1 h p.i., although it did not show the highest GRPR affinity, while [99mTc]Tc-N4-[α-Me-Trp8]MJ9, which revealed the second highest GRPR affinity, exhibited the second lowest activity levels in the tumor at 1 h p.i. Moreover, the latter conjugate displayed enhanced activity levels in most non-tumor organs, especially visible in the pancreas.