In the low- and immediate risk PCa group, the PSA level was significantly higher in the 68Ga-PSMA PET/CT positive patients than in 68Ga-PSMA PET/CT negative patients (15.7 ± 6.8 ng/ml vs. 8.8 ± 4.2 ng/ml; p = 0.014). Here, KLK3 is linked to posterior cortical atrophy.