KLK3 and posterior cortical atrophy: The division of GS into 6 vs. 7 vs. 8–10 together with corresponding grouping of the prostate specific antigen (PSA) and clinical stages into three groups—low, intermediate and high PCa risk groups,—are known as D'Amico classification (3) that has been adopted in clinical practice and has been widely used for prognostic and therapeutic purposes.