Screening for Prostate Cancer May Not Reduce Men's Risk of Dying from the Disease, New England VA Study Says

Jan 11, 2006. According to a Veterans' Affairs study published in the January 9 issue of Archives of Internal Medicine, men who died of prostate cancer under VA care in New England in the 1990s included some men who had, since the introduction of the PSA test in 1986, undergone at least one screening for prostate cancer before receiving their diagnosis.

John Concato, M.D., M.P.H., from the Veterans Affairs (VA) Connecticut Healthcare System, West Haven, and Yale University, New Haven, and colleagues conducted this study to find out whether screening for prostate cancer with prostate specific antigen (PSA) blood test improved the chances of survival for men in the 1990s.

About the same numbers of men treated at the VA for other conditions -- men who did not die of prostate cancer -- also were screened for the disease. Since these men did not die of the disease yet were no more likely to have been screened for it, this study concludes that screening has no effect on prostate cancer survival.

The study

From approximately 72,000 veterans receiving health care at any of 10 VA medical centers in New England, they identified 501 men age 50 years and older who were diagnosed with prostate cancer between 1991 and 1995 and who had died of prostate cancer sometimes between 1991 and 1999.

A comparison group of 501 living men was constructed. Each man in this control group was matched, for age and for treatment at the same center, to a man with prostate cancer who had died.

Medical records were reviewed to determine whether men in either group had ever been screened for prostate cancer.

Seventy -- or 14% -- of the men who had died of prostate cancer had been screened with PSA at least once before their diagnosis. And 65 (13%) of the live men in the control group had been screened.

The authors say that if PSA screening prevented death from prostate cancer, fewer men who died would have received screening compared to the men who were living.

In addition, they say, screening was not found to reduce mortality among men who were younger or healthier or when digital rectal exams were also considered.

According to the authors, screening tests can increase the detection of cancer, even at earlier stages, but not necessarily prolong survival.

"Optimal clinical strategies for diagnosing and treating prostate cancer remain uncertain and in need of additional investigation," they write. "Based on available evidence, including the present study, recommendations regarding screening for prostate cancer should not endorse routine testing of asymptomatic men to reduce mortality. Rather, the uncertainty of screening should be explained to patients in a process of 'verbal informed consent,' promoting informed decision making."

The authors provide no evidence that men who died of prostate cancer in care of the VA in New England in the 1990s despite some pre-diagnosis screening actually had been diagnosed at stages of the disease amenable to cure. They do not establish or discuss whether all screening results had been interpreted correctly. They do not mention whether any of the men who died of prostate cancer fell victim to the well-known syndrome of failure to diagnose.