Current guidelines of European Association of urology recommend this examination only for high-risk PCa patients, i.e., patients who have an initial PSA level ≥ 20 ng/mL, a pathologically ISUP grade of 3 to 5, or a clinical stage of T3 or greater at the time of PCa diagnosis, which means the tumor has exceeded the prostate capsule. Here, KLK3 is linked to neoplasm.