Mammograms Reduce Risk of Breast Cancer Deaths by 21% Among Women Ages 40 to 74, Swedish Study Finds
In the latest in the ongoing debate over the effectiveness of mammograms, a new analysis of four Swedish mammogram studies indicates that the test can reduce breast cancer deaths, the Washington Post reports. Swedish researchers from Umea University analyzed four long-running Swedish studies involving more than 247,000 women between the ages of 40 and 74. The results, which are published in tomorrow's edition of the journal the Lancet, indicate that the risk of dying from breast cancer was approximately 21% lower for women who underwent regular mammograms than women who did not (Okie, Washington Post, 3/15). The "greatest" benefit was seen among women in their 60s, with the risk of dying from breast cancer decreasing by 33% among those who received regular mammograms (Lasalandra, Boston Herald, 3/15). Deaths from breast cancer among women ages 55 to 64 who received regular mammograms dropped by 27%. In comparison, deaths from breast cancer among women ages 45 to 54 who were screened fell 14%.
The New York Times reports that the new research "is unlikely to settle the debate among scientists and statisticians over the value of mammograms" (Stolberg, New York Times, 3/15). Last October, Danish researchers said that they had found "serious flaws" in seven large studies on mammograms, including the four the Swedish researchers analyzed, which prompted advisers to the National Cancer Institute to conclude in January that the "benefits of mammograms might not outweigh the risks." However, the Bush administration last month issued a recommendation in favor of mammograms every one to two years for women ages 40 to 69 (California Healthline, 3/1). The Times reports that when the authors of the new study adjusted their findings to account for the criticism raised by Danish researchers, the rate of death from breast cancer for women who received regular mammograms fell to just 15% (New York Times, 3/15). The new study's authors also said that their findings "can't be regarded as state of the art" because the analysis is based on studies that took place between the 1960s and the late 1980s, "when doctors used screening technology long since eclipsed by better mammography equipment" (Smith, Boston Globe, 3/15). Karen Gelmon and Iva Olivotta, cancer experts from the British Columbia Cancer Agency who wrote an editorial accompanying the study, said "even a 21% reduction" is "barely measurable" when you take into account that breast cancer accounts for "only" about 4% of all deaths annually (Boston Herald, 3/15). Still, Gelmon said, "It's reassuring. There is a real effect (of mammograms), certainly for older women and possibly for younger ... and that effect is modest" (Washington Post, 3/15). However, proponents of mammograms rejected that the benefits are modest. Dr. Peter Greenwald, director of cancer prevention at the National Cancer Institute, said, "I wouldn't use [modest]. I think when you get a reduction of one-fifth in deaths from breast cancer, that's very important" (New York Times, 3/15).
This is part of the California Healthline Daily Edition, a summary of health policy coverage from major news organizations. Sign up for an email subscription.