Individually, PCA3 could distinguish biopsy-confirmed healthy men and PCa patients with an AUC of 0.681 (Motamedinia et al., 2016), whereas in combination with ERG mRNA and SPDEF as normalizer, it constitutes the ExoDx Prostate test that is routinely used for detection of high-grade PCa in men over 50 years of age and gray zone PSA levels (2–10 ng/mL), and informs whether to proceed with prostate biopsy (Tutrone et al., 2020). The gene discussed is KLK3; the disease is posterior cortical atrophy.