Prospective longitudinal evaluation of men with initial prostate specific antigen levels of 4.0 ng/ml or less

Purpose: We evaluated the 3-year longitudinal changes in serial serum prostate specific antigen (PSA) levels in men with an initial PSA of 4.0 ng./ml. or less and no suspicion of prostate cancer. Materials and Methods: A total of 760 men with an initial PSA of 4.0 ng./ml. or less plus a normal or suspicious digital rectal examination and a benign prostate biopsy was enrolled into an every 4-month PSA monitoring study. Results: Of the 559 men with an initial PSA of 2.0 ng./ml. or less only 3 (0.5%) had a persistently abnormal PSA for 3 years and 1 cancer (0.2%) was detected, and 48 men had a PSA velocity of 0.8 ng./ml. per year or more at year 1 but only 1 (2%) had a persistent rate of increase (2.4 ng./ml. per year) at 3 years. Of the 201 men with a PSA of 2.1 to 4.0 ng./ml. 85 had an abnormal PSA but only 37 (43%) met the criteria for biopsy. Only 8 of 23 biopsies (35%) revealed cancer. Of the 201 men 24 had a PSA velocity of 0.8 ng./ml. per year or more at year 1 but only 4 had persistence for 3 years. All 4 men had cancer but they were identified as at high risk by PSA criteria. Conclusions: Men with a PSA of 2.0 ng./ml. or less are at low risk for an abnormal PSA or cancer within 3 years and annual monitoring may not be necessary. However, annual monitoring is clinically useful in men with an initial PSA of 2.1 to 4.0 ng./ml. Also, serial monitoring with interval testing in men whose PSA becomes greater than 4.0 ng./ml. is beneficial in identifying a high risk group requiring biopsy. Finally, PSA velocity did not add further to cancer detection in this population.