PSA velocity: Useful in cancer screening?

Some studies suggest the rate of change of prostate-specific antigen (PSA) levels predicts prostate-cancer survival. But this does not necessarily mean that PSA velocity is ready for use as a prostate-cancer-screening tool, according to a commentary in the Oct. 9 online edition of the Journal of the National Cancer Institute.

PSA velocity has been the subject of much research and debate since the beginning of the PSA-screening era. Researchers initially thought knowledge of PSA velocity could decrease the number of men with elevated PSA levels who have unnecessary biopsies. However, today, PSA velocity is being used to uncover cancers in men with normal and even low PSA levels.

Dr. Ruth Etzioni of the Public Health Sciences Division and colleagues reviewed several recent articles on PSA velocity. They pointed out that studies linking PSA velocity with survival differ from prospective-screening studies in a number of important ways.

To date, prospective-screening studies have not found a clear link between PSA velocity and the likelihood of high-risk prostate cancer once the level of PSA is known. No studies to date have addressed the costs and benefits of using PSA velocity for prostate-cancer screening.

"One of the main goals of this commentary has been to reconcile some of the inconsistencies across studies by highlighting features of study design and potential sources of bias that might explain why different types of studies have produced differing results," the authors wrote.

[From a Journal of the National Cancer Institute news release.]