A detectable level of prostate-specific antigen (PSA) is the first indicator of recurrent prostate cancer after radical prostatectomy. In a new Mayo Clinic study, the concept of PSA doubling time (DT) is found to be a reliable tool to distinguish which patients have prolonged innocuous PSA levels after therapy from those who are at great risk for disease recurrence and death from prostate cancer. Doubling time is defined as the duration for PSA levels in the blood to increase by 100 percent.
Mayo’s study, published in the April issue of Mayo Clinic Proceedings, concludes that patients with a PSA doubling time of less than three months after therapy are at imminent risk of death from prostate cancer. Patients with a doubling time of three to 12 months are at a significant risk for the development of systematic disease and cancer-specific death.
According to the authors, the new findings should prompt physicians whose patients have doubling times of less than one year to treat them with systematic therapies. Patients with PSA doubling times of one to 10 years are more likely to have a local rather than systematic recurrence, and patients with a PSA doubling time of greater than 10 years are at a low risk of recurrence.
Authors of the study are Michael Blute, M.D.; Matthew Tollefson, M.D.; and Bradley Leibovich, M.D., all from the Mayo Clinic Department of Urology; and Jeffrey Slezak from Mayo’s Division of Biostatistics.
Journal
Mayo Clinic Proceedings