Determining Ideal PSA Thresholds for Predicting Prostate Cancer

The study used data from the Veterans Affairs (VA) Health Care System database. Men included in the analysis were age 40 years or older, had a baseline PSA at or below 4.0 ng/ml, were not taking 5- alpha reductase inhibitors (such as Avodart, Proscar or Propecia) and had not been previously diagnosed with prostate cancer. The men were followed for 4 years. The final analysis included 41,250 Caucasian and African-American men. Approximately 3% of the men had prostate cancer, and mean time to prostate cancer diagnosis was 2 years.

The ideal PSA threshold for predicting future prostate cancer in Caucasian men was 2.5 ng/ml. The ideal threshold for African-American men was even lower at 1.9 ng/ml. Across all patients, the optimal PSA threshold was 2.4 ng/ml.