Many studies have demonstrated the usefulness of PSA Velocity (PSAV) in prostate cancer screening. However, the often dramatic elevations in PSA values observed in men with prostatitis (PR) could potentially cause confusion in the use of PSAV for CaP diagnosis.
What is the relationship between PR and PSA activities and measurements over the year prior to prostate biopsy and how does antibiotic treatment fit into the picture?
What We Found In Our Studies:
Men with rapidly rising PSA levels should have a course of antibiotic therapy to determine if the PSA decreases.
However, our results show that a negative PSAV following antibiotics does not eliminate the presence of CaP.
If the PSA does not decrease to a level below the biopsy threshold, 2.5 ng/mL, a biopsy should still be performed. Over the short term, prostatitis can confuse PSAV interpretations, but over a longer period, men with prostate cancer have a significantly higher PSAV.
We examined 965 patients with sufficient PSA measurements to enable a PSAV calculation and documentation of either prostate cancer, prostatitis or both. Because it is our practice to recommend antibiotics and a repeat PSA measurement prior to biopsy for men with a suspicion of PR, we were also able to determine the PSAV after antibiotic treatment.
In our first measurements, less than 70 days before biopsy, antibiotic therapy resulted in a negative PSAV for those with PR alone or CaP with PR. Over this brief time, PSAV was highest for patients with CaP alone. However, when the PSAV was calculated over the year prior to biopsy, PSAV was similar between men with CaP alone and those with PR and CaP.
Furthermore, comparisons showed that PSAV was significantly higher in men with CaP, whether or not PR was also present, compared to those with prostatitis alone.
Brian T. Helfand, MD, PhD, Chicago, IL; Stacy Loeb, MD, Washington DC; Christopher B. Anderson, John Cashy, MD, Joshua J. Meeks, MD, PhD, C. Shad Thaxton, MD, PhD, Chicago, IL; Kimberly A. Roehl, St. Louis, MO; William J Catalona, MD, Chicago, IL