Currently, men who experience a rapidly rising PSA (prostate specific antigen) level are referred for a prostate biopsy even when they have no other indications of prostate cancer. A new study, however, finds that such prostate biopsies are unnecessary if men have a normal clinical exam and their total PSA levels are not yet high.
According to Andrew Vickers, PhD, the lead author of the new study from Memorial Sloan-Kettering Cancer Center, “if a man’s PSA has risen rapidly in recent years, there is no cause for concern if his total PSA level is still low and his clinical exam is normal.” The rate PSA rises is known as PSA velocity.
To arrive at this conclusion, the researchers evaluated data from 5,519 men who participated in the Prostate Cancer Prevention trial. All the participants were 55 years or older, had no previous history of prostate cancer, and had normal digital rectal findings and PSA levels of 3.0 ng/mL or less.
The men were randomly assigned to take either finasteride (a medication used to treat BPH) or placebo for seven years. Each year, all the men were screened for PSA levels, and those who had a PSA greater than 4.0 ng/mL were advised to have a prostate biopsy. At the end of the study, men who did not have prostate cancer were asked if they would consent to a biopsy.
When the scientists reviewed the PSA and biopsy results, they found the factor that predicted the risk of cancer was a man’s PSA level, not how rapidly the PSA rose. Men with a steady PSA of 5 ng/mL was more likely to have prostate cancer than those whose PSA rose from 2.5 to 3.4 ng/mL. They concluded that a rapidly rising PSA should not be included in screening guidelines for prostate cancer.
Read more in our Prostate Cancer Health Center.
Vickers AJ et al. An empirical evaluation of guidelines on prostate-specific antigen velocity in prostate cancer detection. Journal of the National Cancer Institute 2011Mar 16; 103(6): 462-69