Unlike PSA, which lacks specificity to distinguish between benign conditions and cancer [36], specific miRNA expression ratios (miR-1913/miR-3659 and miR-H9/miR-3659) have shown promise in differentiating PCa patients from healthy individuals, particularly in the grey zone of PSA levels (3–10 ng/mL). Here, KLK3 is linked to posterior cortical atrophy.