When combined with other promising structures into a PCa-specific diagnostic model, the so-called PSA G-index, an AUC of 1.00 could be achieved for 15 PCa and 15 BPH patients, compared to 0.50 and 0.60 for tPSA and fPSA%, respectively [123]. Here, KLK3 is linked to benign prostatic hyperplasia.