Using our nomogram, in patients with this cut-off of PSA density and therefore diagnosed with PCa, the probability of identifying a high-grade PCa was 18%, while for a low-grade tumor, it was 35%: these results indicate that our nomogram could be able not only to help in selecting patients who should undergo a biopsy but also to stratify the aggressiveness of cancer itself. This evidence concerns the gene KLK3 and neoplasm.