The decision of how often to get a mammogram just keeps getting more complicated.
According to Reuters, a new study bolsters previous reports that mammograms do not make it less likely that women will die of breast cancer. Here are excerpts from the article:
A new study has added to growing evidence that yearly mammogram screenings do not reduce the chance that a woman will die of breast cancer and confirms earlier findings that many abnormalities detected by these X-rays would never have proved fatal, even if untreated.
The research, published in the British Medical Journal, is the latest salvo in a decades-long debate over the benefit of mammograms. The 25-year study of 89,835 women in Canada, aged 40 to 59, randomly assigned the volunteers to receive either annual mammograms plus physical breast exams or physical exams alone.
The women started receiving mammograms from 1980 to 1985. At the time, doctors believed screening saved lives by detecting early-stage cancers, which were considered more treatable than cancers detected later, especially in women aged 50 to 64.
Instead, the study “found no reduction in breast cancer mortality from mammography screening,” the scientists wrote, “neither in women aged 40-49 at study entry nor in women aged 50-59.”
The findings echo research such as a 2012 study in The New England Journal of Medicine which found that screening mammography “is having, at best, only a small effect on the rate of death from breast cancer.” On the basis of similar findings going back to the 1990s, the U.S. Preventive Services Task Force, an independent panel of medical experts, in 2009 recommended biennial screening mammography for women 50 to 74 years, replacing an earlier recommendation that women start having mammograms every one to two years at age 40.
Proponents of mammograms often point out that women whose breast cancer is diagnosed by mammography alone live longer than those whose cancer is diagnosed by physical exam. This study found that as well, but the apparent advantage was illusory, the researchers concluded. For one thing, if a cancer is sufficiently aggressive and resistant to treatment it will likely prove fatal no matter when it is detected. Finding it in 2011 by physical exam, as opposed to 2007 by mammogram, simply means that the woman lives longer knowing that she has cancer, not that she lives longer overall.
In a statement, the American College of Radiology and Society of Breast Imaging called the BMJ study “an incredibly misleading analysis.” The results “should not be used to create breast cancer screening policy as this would place a great many women at increased risk of dying unnecessarily from breast cancer.”