Analyzing prostate-specific antigen (PSA) velocity and its rate of increase over time may help physicians better assess which patients require biopsy and active treatment and could, according to researchers from Innsbruck, Austria, result in significant healthcare savings. These data were presented during the 105th Annual Meeting of the American Urological Association (AUA). The session was moderated by William J. Catalona, MD, an expert in prostate cancer and PSA.

“We have made exciting discoveries since the abstract was submitted,” said Jasmin Bektic, MD, who presented the data. “The growth rate in PSA from cancer based on PSA velocity is a strong predictor of the risk of high Gleason cancer. High sensitivity to high-risk cancer along with good specificity to no cancer can be achieved using growth rate and PSA variation around trend.”

Using data from participants in the Tyrol project, researchers analyzed PSA velocity, or the rate of PSA change, in 426 prostatectomy patients with four years of periodic PSA tests. These patients were categorized into four groups: those with recurrence following radical prostatectomy; those with Gleason grade 8-10 tumors without recurrence; those with Gleason grade 5-6; and those with stage T1-T2a tumors without recurrence and with negative surgical margins.

Using a mathematical construct, investigators calculated the rate of PSA increase. Patients whose cancer ultimately recurred had PSA velocity readings of at least 0.25 ng/ml/yr (median 1.01), with only 7 percent having a velocity under 0.4 ng/ml/yr. Twenty-one percent of the Gleason 8-10 cancers that did not recur had a velocity of less than 0.4 ng/ml/yr. The least aggressive cancers had a median PSA velocity of 0.36 ng/ml/yr, with 53 percent below 0.4 and 36 percent below 0.25 ng/ml. These data suggest that indolent tumors can be identified not only by Gleason score, but also by PSA velocity.

“Monitoring PSA velocity over time gives us valuable information that can help us better assess which tumors are slow-growing and which ones may kill,” said William J. Catalona, MD, the briefing moderator. “Further analysis of these changes improves the specificity of the PSA test and can help us better decide when biopsy and active treatment might be necessary. It helps make PSA a smarter test.”

“The PSA test is a very effective marker when interpreted appropriately.”

Source
American Urological Association