Certain men age 75 to 80 are unlikely to benefit from routine prostate specific antigen (PSA) testing, according to a Johns Hopkins study published in the April 2009 issue of The Journal of Urology.
The researchers found that men in this age group with PSA levels less than 3 nanograms per milliliter are unlikely to die of or experience aggressive prostate cancer during their remaining life, suggesting that the use of PSA testing in many older men may no longer be needed.
The study, led by researchers from the Johns Hopkins University School of Medicine and the National Institute on Aging's Baltimore Longitudinal Study of Aging (BLSA), reviewed data from 849 men (122 with and 727 without prostate cancer) who were participating in the BLSA and who had undergone regular PSA testing.
Results showed that among men who were over 75 with PSA levels less than 3 nanograms per milliliter, none died of prostate cancer and only one developed high-risk prostate cancer. In contrast, men of all ages with a PSA level of 3 nanograms per milliliter or greater had a continually rising probability of dying from prostate cancer.
If confirmed by future studies, these results may help determine more specific guidelines for when PSA -based screening might be safely discontinued, according to lead investigator Edward Schaeffer, M.D., an assistant professor of urology at Johns Hopkins. While PSA screening remains a useful tool for helping detect early stages of prostate cancer and is credited with decreasing prostate cancer mortality, discontinuing unneeded PSA testing could significantly reduce the costs of screening and also potentially reduce morbidity resulting from additional tests or treatments.
"We need to identify where we should best focus our health care dollars by concentrating on patients who can actually benefit from PSA testing," Schaeffer says. "These findings give a very strong suggestion of when we can start to counsel patients on when to stop testing."
Other Johns Hopkins researchers who participated in this study include H. Ballentine Carter, M.D., Anna Kettermann, M.A., Stacy Loeb, M.D., Luigi Ferrucci, M.D., Ph.D., Patricia Landis, B.S., Bruce J. Trock, Ph.D., and E. Jeffrey Metter, M.D.