Use of nomograms for early detection in prostate cancer.

Since the first introduction of prostate-specific antigen (PSA) as a screening tool in the 1980s, the accurate diagnoses of clinically significant prostate cancer remains a challenge. Analysis of a correlation between PSA levels and prostate biopsies of men with PSA 3 ng/mL or less in the placebo group of the Prostate Cancer Prevention Trial suggested that no "normal" PSA level exists. With the acknowledgement that PSA level is considered a continuum rather than a dichotomous marker, accurately diagnosing clinically significant prostate cancer is even more challenging. Nomograms are increasingly being used as tools in the clinical setting to address this challenge. Through incorporating multiple clinical factors, such as PSA, digital rectal examination, age, race, prostate volume, family history, and previous negative biopsy, risk calculators can improve sensitivity of diagnosis over using a PSA cutoff alone. This article discusses the rational for the use of nomograms and the advantages and limitations for the most commonly used nomograms.