Our investigation in a large prospective cohort of 1057 biopsied men showed a significantly larger area under the ROC curve (AUC) for Prostate Health Index (PHI) density (PHID) in comparison with PHI alone. In this well-balanced group with 552 men with prostate cancer (PCa) and 505 without PCa from two tertiary centers in Germany the AUC for PHID was 0.835 and for PHI 0.801 (p=0.0013).