Friday, May 27, 2016
PSA Ratio Test - Is It Valuable?
I had RRP and undergone external radio theraphy. My last PSA test (15 months after my treatment) was 0.05. Lately my family doctor advised me to have my PSA Ratio checked. At this stage that my cancer was diagnosed and treated. Is the PSA Ratio test necessary? How valuable is this test?
When you say your "doctor", I am uncertain if you mean your primary care physician or your urologist. To the best of my knowledge, the PSA "ratio" (which I believe is what I refer to as PSA by which I mean total PSA ratio to serum free PSA which is usually reported as percent serum free PSA) has no relevance in monitoring a patient who has been treated for prostate cancer. The total PSA is the benchmark by which we judge response to treatment of prostate cancer.
With the development of more sensitive PSA assays, the lower limits that can be accurately measured is 0.05 ng/ml which is your current level. Some laboratories report less than (< symbol) 0.05 ng/ml and some laboratories report 0.05 ng/ml. However, the difference is moot. I would typically recheck total PSA each 3 months following treatment completion for the first year, and, if no change, then every 6 months for the second year and annually thereafter. Hopefully this helps.
James F Donovan, Jr, MD
Professor of Surgery
Director of UC Urology
College of Medicine
University of Cincinnati