The number of breast cancer deaths in middle-aged women is not reduced by yearly mammogram tests, according to a 25-year study published in the British Medical Journal.
After testing 90,000 women ages 40 to 59, the Canadian researchers found that over the 25-year period, the same number of women died from breast cancer whether they received mammogram testing or not.
The goal of mammography is early detection and diagnosis of breast cancer, but the testing is not foolproof. Just because the cancer is detected early does not necessarily mean that it can be cured, and sometimes cancers detected in late stages do have effective treatments. On the other hand, overdiagnosis is possible, meaning tumors found by the mammogram are benign and have no affect on a woman's life span. One study found that 22 percent of breast cancers spotted by mammograms were the result of overdiagnosis.
The report also observed that one in 424 women who got a mammogram were falsely diagnosed as having breast cancer.
Dr. Anthony Miller, professor emeritus at the University of Toronto and one of the study's researchers, made a statement about how modern day treatments come into play in a mammogram's usefulness.
"If you're able to cure cancers by treatment, no matter what stage they're at, there isn't any role for screening," he said. "So as the treatment improves, the contribution of screening gets less and less."
Organizations still recommend women get annual mammograms, however, depending on their age. The U.S. Preventive Services Task Force believes women ages 50 to 74 should get them every two years, while the American Cancer Society recommends yearly screening starting at age 40. Either way, Miller says, if women are concerned about an unusual lump or distortion on their breast, they should get a mammogram because that is when it can make a difference.
