KLK3 and posterior cortical atrophy: Then, the receiver operating characteristic (ROC) analysis indicated that AFU had a better value for PCa diagnosis than F/T PSA especially in specificity (the area under the ROC curve (AUC): 0.630 vs. 0.612) (Figures 1C, D), and the AFU optimal cutoffs for PCa was 19.5 U/L.