It came as a surprise to many men and their doctors when the US Preventive Services Task Force (USPSTF), a federal agency that sets standards for medical practice, recommended two years ago that prostate-specific antigen (PSA) screening be stopped. Altogether. For all men. The test, the USPSTF concluded, was causing more harm than good.
Since then, many experts and professional groups, including the American Urological Association and American Cancer Society, have sharply disagreed with that recommendation, arguing that PSA testing is too valuable to give up.
So what is the best approach for men? For the latest thinking on PSA screening—and details on important new tests that help prevent unnecessary biopsies—we turned to Peter T. Scardino, MD, a renowned authority on prostate cancer.
His advice: Don’t throw out the PSA altogether—but rather screen smarter to maximize the good and minimize the harm associated with the test. Here’s how…
WHAT’S WRONG WITH PSA testing?
Prior to the USPSTF recommendation, the PSA was typically given every year to men ages 50 and up. Results above a certain threshold—3 nanograms per milliliter (ng/mL) or 4 ng/mL, depending on how cautious the doctor was in his/her treatment approach—automatically led to a biopsy. If the biopsy found any cancer at all, surgery and/or radiation were usually recommended.
However, there were three problems with this approach…
- A rise in PSA usually doesn’t mean cancer. Many things can affect a man’s PSA level, including benign prostate enlargement…inflammation of the prostate…and a urinary tract infection. Even use of aspirin, statins, diuretics and other medications has been found to have an effect. Result: A lot of men were receiving unnecessary biopsies. Up to one-third who were biopsied experienced such adverse effects as pain, fever, bleeding or serious infection.
- Most prostate cancer isn’t deadly. An estimated one out of three men ages 50 to 70—and nearly three-fourths of those over age 70—have some malignant cells in their prostates, which may sit harmlessly for years. But once cancer is found, it’s hard not to take action. Result: A lot of men have been treated for a disease that would have never caused trouble in their lifetimes.
- Prostate cancer treatment can have lasting effects. Surgery to remove the prostate and radiation to destroy prostate cancer cells carry a high risk for very unpleasant consequences. Up to 40% of men who receive prostate surgery and/or radiation suffer erectile dysfunction. Problems with urinary function were reported in 7% of men who had surgery. Among those who had radiation, 18% experienced urinary difficulties and 9% had problems with bowel function.
THERE IS A BETTER WAY
The question of PSA screening is a personal decision that each man needs to make with the help of his doctor. To provide guidance, doctors at Memorial Sloan-Kettering Cancer Center evaluated all the research on PSA to come up with an approach that gives men the greatest possible benefits of PSA testing while minimizing the potential dangers.
Our approach: Men should begin PSA testing at age 45 (or even younger if there’s a family history of prostate cancer or the man is African-American). If the level is under 1 ng/mL, the test should be repeated every five years until age 60. If it’s still under 1 ng/mL at that time, PSA screening can stop—the man’s risk of ever dying of prostate cancer is negligible.
If PSA at age 45 is between 1 ng/mL and 3 ng/mL, repeat the test every two to four years, until age 70. If it’s still normal, then testing stops. Even if you develop prostate cancer at this point, odds are you’ll die of something else before the malignancy causes you trouble. If you’re age 70 or older and have never been screened, check your PSA once or twice—if it’s under 3 ng/mL, no further testing is needed.
WHEN PSA IS HIGH
Most doctors who treat prostate cancer agree that PSA over 3 ng/mL suggests a possibility of a prostate malignancy that should be investigated. But it’s crucial to remember that a single PSA reading often means nothing—transient elevations as high as 6 ng/mL are not unusual. In this situation, check the PSA level again in six to 12 weeks…if it’s on its way down, repeat the test again two months later. If PSA remains over 3 ng/mL, you can have a biopsy or consider further testing (see below) that can analyze blood proteins in more detail.
New testing options: Ask your doctor about the Prostate Health Index, a new test that measures levels of PSA subtypes. In clinical trials, it reduced the number of men who were biopsied by 50% but still found almost all the cancers that required treatment. The test is now available from Beckman Coulter. A similar test, the 4Kscore (or 4 kallikrein score), has not yet been released, but clinical trials have shown as good or better results.* The 4Kscore blood test is expected to be available from Opko Health later this year.
WHEN it’s CANCER
If a man’s prostate biopsy is positive for cancer, doctors usually analyze the cancerous tissue to determine his Gleason score, which indicates how likely the malignancy is to spread. A score of 7 means a medium risk of spreading…8 or above means the risk is high. The Gleason score isn’t a perfect predictor of how a cancer will behave. But several new tests have recently become available to give patients and doctors additional valuable clues about a man’s prostate cancer.
New tests all men should know about: The Prolaris (Myriad) and Oncotype DX (Genomic Health) assays analyze molecules that are produced by certain genes that regulate how rapidly cancer cells multiply (the tests are similar, so a man would have one or the other). Use of one of these tests helps determine whether a tumor with a Gleason score of 6 or even 7 must be treated aggressively or can safely be left alone and monitored.
*Dr. Scardino is on the scientific advisory board of the company developing the 4Kscore.