The Prostate Specific Antigen test, commonly known as the PSA test and used to screen for prostate cancer, may not be necessary for men over 75, according to a new study published in the April 2009 issue of The Journal of Urology. The screening has been controversial in the past, and the new study seems to add fuel to the belief that the test could be dropped for some patients.

While some forms of prostate cancer are very slow to enlarge and may never pose a health threat to the man, other forms ... can be life−threatening.

Johns Hopkins researcher Edward Schaeffer and his colleagues studied 849 men, of whom 122 suffered from prostate cancer and 727 were cancer−free. All had undergone routine PSA screening as part of the National Institute on Aging's Baltimore Longitudinal Study of Aging (BLSA). The researchers found that for men who had a PSA reading of less than 3 nanograms per milliliter, none died during the course of the study. Only one patient developed a severe form of prostate cancer. But for those whose PSA readings were above 3 nanograms per milliliter, these men had a "continually rising" likelihood of dying from the disease.

While some forms of prostate cancer are very slow to enlarge and may never pose a health threat to the man, other forms are quite malignant and can be life−threatening.

Prostate specific antigen levels naturally rise as men age and the prostate enlarges. Though high levels can be a strong indicator of prostate cancer, they can also be due to other phenomena like injury, inflammation, and sexual activity.

Schaeffer says that if future studies confirm the results found here, this may help construct more concrete guidelines for when PSA testing may no longer be required.

While PSA testing has reduced the mortality rate from prostate cancer, there is also the issue of how to best conserve healthcare funds, particularly in these difficult economic times. "We need to identify where we should best focus our health care dollars by concentrating on patients who can actually benefit from PSA testing," says Schaeffer. "These findings give a very strong suggestion of when we can start to counsel patients on when to stop testing."