Following the introduction of transrectal ultrasonogra-phy of the prostate, there was a great deal of enthusiasm regarding its use in the early detection of prostate cancer. It was felt that TRUS would be able to detect many non-
palpable small tumors that were missed by DRE alone.20 However, studies have shown that TRUS has several limitations with regard to its use as a screening test for prostate cancer.
Most importantly, TRUS has low positive and negative predictive values, which were reported to be 36 and 89%, respectively, in one study.21 Cooner and colleagues reported the positive predictive value of TRUS to be only 16% in men with a palpably benign prostate.22 This number drops to 9.8% when both DRE and PSA are normal. Additional limitations of TRUS as a screening tool include the procedure's invasiveness, cost, and limited detection rate when the less invasive DRE and PSA are normal. It is the authors' belief that the major value of TRUS is its ability to allow for anatomic sampling of the prostate when other screening tests are abnormal.
Was this article helpful?