Prostate Cancer: PSA Change May Be Key to Risk
Researchers Say Tracking PSA Changes Indicates Who's at Risk of Dying When Cancer Returns
PSA Velocity continued...
"Our study shows that men who experience a two-point rise in PSA in the year preceding a diagnosis of prostate cancer -- despite a low level of PSA and despite a biopsy showing a supposedly 'favorable' prostate cancer -- have more aggressive cancer and need more aggressive treatment to cure it."
Men whose PSA levels rose more than two points in a year had a 12-fold higher risk of dying from prostate cancer than men whose PSA levels rose less quickly.
"The median survival for rapid risers is only six years, and that is very short for prostate cancer," D'Amico says. "The bottom line for patients is this: Get a PSA test annually and know the result. Because even if your doctor isn't looking at year-to-year change, at least you can. We recommend getting a baseline PSA test at age 35, especially for men whose dads had prostate cancer."
Zeroing In on Prostate Cancer Death Risk
Many men elect to have their prostate glands removed when they are diagnosed with prostate cancer. With no prostate, their PSA levels should drop to zero. But within 10 years of surgery, more than a third of these men eventually have PSA appear in their blood.
Where does the PSA come from? Prostate cancer cells that have begun to grow again. But that's not always bad news. These recurrent cancers often grow very slowly.
"The nice thing is that a PSA test can identify cancer recurrence years before we would detect it clinically," Freedland says. "But then, it is hard to figure out who has aggressive cancer and who doesn't."
After looking at hundreds of cases, Freedland's team came up with three things that predict which men are likely to have problems:
- How quickly the PSA became detectable after surgery. Men whose PSA came back more than three years after surgery did better than those whose PSA came back in three years or less.
- The most important factor, however, is how fast the PSA goes up. This is the doubling time -- how long it took for a PSA of 1 to become 2, and 4, and 8, and so on.
- The Gleason score of the original tumor. Gleason score is based on what a cancer looks like under the microscope. The higher the score, the more aggressive looking the cancer. Men with Gleason scores of less than 8 did better than those with Gleason scores of 8 or more.