GRPR and posterior cortical atrophy: [99mTc]Tc-DB8, a GRPR-imaging SPECT tracer, demonstrated a high detection rate for primary PCa lesions similar to PET tracers [68Ga]Ga-RM2, [68Ga]Ga-SB3, [68Ga]Ga-BAY-7548, and [68Ga]Ga-NOTA-RM26, 84–89% [44,51,52,53,55,56,57].