Prostate cancer test has little benefit, study finds
MUNICH — Screening men for prostate cancer saves few lives and comes at the risk of unnecessary treatments, a study found, adding to uncertainty over the testing’s usefulness.
The routinely used PSA blood test didn’t reduce the number of cancers or overall deaths, according to a review of more than 380,000 men who participated in six previous studies. The review was published yesterday in the British Medical Journal.
While screening raised the chance of a cancer diagnosis, finding more tumors early fails to cut deaths in part because prostate cancer grows very slowly, said University of Florida associate professor Philipp Dahm, who led the study.
“If we pool together all high-quality studies that exist, rather than picking and choosing evidence, the conclusion is that there is no impact on mortality,’’ Dahm said in a phone interview.
The American Cancer Society changed its guidelines this year to reflect the growing uncertainty over testing.
Screening for prostate cancer involves blood tests to measure levels of PSA, or prostate-specific antigen, a protein that can increase because of benign prostate conditions or cancer, according to the National Cancer Institute.
The study is limited because it didn’t record the effect on quality of life or information on the side effects of screening, Dahm said. The results don’t preclude that a longer follow-up could show some benefit, he said.
Side effects of prostate-cancer treatments include incontinence, erectile dysfunction, and other complications, according to the National Cancer Institute.
“In addition to the uncertain benefit on mortality, the human and economic costs associated with PSA-based screening are substantial, primarily as a result of overdiagnosis and overtreatment,’’ Gerald Andriole, chief of urological surgery at the Washington University School of Medicine in St. Louis, said in an accompanying editorial.
In its revised guidelines, the American Cancer Society says men should be screened only if they have been told of the possibility of misleading test results and side effects of treatments that in some cases might pose more harm than the disease.