GRPR and posterior cortical atrophy: Unfortunately, effective doses for GRPR antagonists were not published yet [20], but effective doses for [99mTc]Tc-maSSS-PEG2-RM26 were found to be similar to doses reported for 99mTc-labeled GRPR agonistic imaging probes (0.009 ± 0.001 mSv/MBq for mixed cohorts of PCa and BCa patients [26] and 0.005 ± 0.002 mSv/MBq for PCa patients) [35].