Understanding PSA and prostate cancer risk assessment.

The specificity of serum PSA in screened populations is relatively low because of its inability to discern benign causes of PSA elevation from occult malignancy. An improved understanding of this widely available serum test and the availability of new modalities, such as endorectal MRI, may allow the early detection and treatment of cancer in those men who have it and may avoid unnecessary repetitive prostate biopsies in men with benign conditions.