PSA Test Still Important to Detect Prostate Cancer, Studies Find
Monday, May 21, 2007; 12:00 AM
SUNDAY, May 20 (HealthDay News) -- Despite questions as to whether early screening for prostate cancer is accurate, new research suggests it continues to be important.
And even more encouraging news indicates that statins, drugs designed to lower cholesterol, might also reduce the risk of developing prostate cancer. Both sets of findings were presented Sunday at the American Urological Association's annual meeting, in Anaheim, Calif.
Screening for prostate cancer has become controversial, particularly the issue of whether a prostate-specific antigen (PSA) blood test is useful as an early detector of malignancy. Two studies presented at the conference indicate it is still worthwhile to have such a test.
In one study, Dr. Hans Lilja, from Memorial Sloan-Kettering Cancer Center in New York City, and colleagues found that PSA testing of men in their 40s was predictive of developing prostate cancer later. In fact, the higher the initial PSA, the greater was the probability that the cancer would be aggressive, the research showed.
As recently as last month, a study published in theJournal of the National Cancer Institutefound that PSA tests "perform poorly in distinguishing between those who develop a lethal prostate cancer from those at low or no risk of disease progression."
But among the patients in the Sloan-Kettering study, risk for prostate cancer was concentrated, with 89 percent of advanced cancers occurring in men with the top 10 percent of PSA levels, the researchers found.
Lilij thinks that men should have an initial PSA test when they are in their 40s rather than waiting. "It is surprising that this marker can predict cancer 20 years later," he said. "We should focus our efforts on those men who are on the highest risk for cancer."
Another study found that among patients who had a radical prostatectomy (removal of the prostate and some of the tissue surrounding it), those who had been screened for prostate cancer were more likely to have malignancy confined to the prostate, compared with men who had not been screened.
"Patients should be screened," said lead researcher Dr. Alexandre E. Pelzer, from the Medical University Innsbruck, Austria. "Screening reduces mortality from prostate cancer by 50 percent in our part of Austria, where screening is done, compared with other parts of the country where it isn't," he said.
Another debate in prostate cancer care is whether patients diagnosed with the disease should be treated immediately or whether watchful waiting is best.
In one study, Dr. Marc A. Dall'Era, and colleagues from the University of California, San Francisco, found that it was not possible to predict how fast the cancer would progress among the study subjects who had what was termed low-risk prostate cancer.
In the study, more than 400 men had their cancer watched monthly. "Among the men on active surveillance, about 28 percent progressed," Dall'Era said. "Over five years, none of the men died from prostate cancer," he added.