In the early years of screening for prostate cancer with serum PSA, absolute cutoffs were typically utilized such as greater than 4.0 ng/mL or even 2.5 ng/mL. A biopsy of the prostate would commonly be recommended in a man with greater than 10-year life expectancy who had a confirmed elevation above such a threshold or in the presence of an abnormal digital rectal examination. The unmet need, however, is to be more selective in recommending a prostate biopsy, due to the risk of complications and the high rate of false-positive PSAs. More recently, various clinical nomograms can be used to refine selection. In addition, clinicians can now utilize various advanced serum biomarkers that have enhanced specificity—especially for the patient with a rising PSA with prior negative biopsy. In this chapter, we will focus on the biomarkers PCA3, Prostate Health Index, and 4 K score to illustrate key concepts in biomarker development and clinical utility.
Part of the book: Prostate Cancer