Purpose: We estimated the risk of a rapid prostate specific antigen (PSA) increase in men with a low baseline PSA range of 0.0 to 2.0 ng/ml to investigate the validity of setting a re-screening interval of more than 1 year.
Materials and methods: Between 1988 and 1999, 6,252 men with baseline PSA 2.0 ng/ml or less without suspicious findings on digital rectal examination (DRE) and 7,304 with the same baseline PSA who did not undergo DRE at the time of baseline PSA measurement were re-screened. The risks of a PSA increase to 4.1 to 10.0, 10.1 to 20.0 and greater than 20.0 ng/ml were investigated and stratified by re-screening interval, baseline DRE status, and subdivided baseline PSA ranges of 0.0 to 1.0 and 1.1 to 2.0 ng/ml.
Results: A total of 28 cases (0.2% of 13,556) of prostate cancer were detected after an average re-screening interval of 3.6 years. High PSA above 10 ng/ml at diagnosis was noted in 5 patients (18%), including 2 with a great PSA increase to 1,928 and 298 ng/ml at re-screening intervals of 4 and 6 years, respectively.
Conclusions: Setting 4 to 5-year re-screening intervals for PSA measurements in men with PSA 1.0 ng/ml or less can decrease the cost of PSA tests without lowering sensitivity. A re-screening interval for PSA measurement should be set annually for men with PSA 1.1 to 2.0 ng/ml to minimize the risk of missing aggressive cancer.