PSA-density (PSAD), which normalises the PSA levels against PV, has been shown to be more reliable than PSA alone when detecting PCa in patients with a Gleason Score \documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$\ge 7$$\end{document}12 and can help distinguish between PCa and BPH13. The gene discussed is KLK3; the disease is posterior cortical atrophy.