A study done in the United Kingdom found that the rates of women dying from breast cancer were about the same for women who got mammograms and women who didn’t get mammograms. The researchers concluded that there was no evidence that mammograms were having an effect on the breast cancer mortality rate. Still, there are some concerns about the study.
The research was published in the June 10, 2013 issue of the Journal of the Royal Society of Medicine. Read “Breast cancer mortality trends in England and the assessment of the effectiveness of mammography screening: population-based study.”
In the United States, the value of routine screening mammograms was questioned in November 2009 when the U.S. Preventive Services Task Force (USPSTF) recommended that routine screening mammograms for women with an average risk of breast cancer should start at age 50 instead of age 40. The recommended changes were very controversial and were not universally adopted.
Since that time, the American Medical Association, the American College of Obstetricians and Gynecologists, the American College of Radiology, the American Cancer Society, the National Cancer Institute, and the National Comprehensive Cancer Network all have issued guidelines saying that all women should be eligible for screening mammograms starting at age 40.
Because of the USPSTF recommendations and other reviews questioning the value of screening mammograms, the English Department of Health sponsored a report in 2011 that found that breast cancer deaths had gone down by 20% among women who were eligible for screening mammograms. The report also said that for each breast cancer death prevented, about three overdiagnosed cases were found and treated.
Overdiagnosis means either:
- a screening mammogram finds a suspicious area that would have been eventually diagnosed as cancer by other means, without any effect on prognosis
- a screening mammogram finds a suspicious area that never would have affected a woman’s health if it hadn’t been found or treated
Because the report didn’t end the mammography controversy, the researchers who did this study decided to look at the codes on death certificates to see if certificates that listed multiple causes of death were affecting breast cancer death rates.
Until the mid-1990s, death certificates in the United Kingdom listed only the primary cause of death, even if more than one condition contributed to the death. Now, all contributing causes are listed on death certificates.
The researchers looked at two databases:
- the death registry for the entire country
- a death registry from the Oxford region
Unlike the rest of the country, the Oxford region has always listed all causes on death certificates.
The researchers found that from 1979 to 2009, deaths from breast cancer in the Oxford region dropped by 2.1% each year for women ages 40 to 49. This age group isn’t included in the national mammogram screening program. Deaths from breast cancer dropped by the same rate in Oxford women ages 50 to 64. This age group is included in the national mammogram screening program.
The researchers concluded that there was no evidence showing that breast cancer death rates had dropped more for women who were in the national screening program compared to women who weren’t in the screening program.
Still, there are some questions about the study. Overall, younger women are less likely to be diagnosed with breast cancer. But when they do develop breast cancer, the cancer is likely to be more aggressive and faster-growing than breast cancer diagnosed in older women. So while the breast cancer death rate dropped in younger women (likely due to improvements in treatment), would it have dropped more if younger women had been getting annual mammograms?
It’s also not clear if the researchers accounted for any other factors that may have affected whether or not the women died from breast cancer. Were there treatment delays? Did the older women smoke and drink more? Were a majority of the women overweight or obese? Did the women exercise? All of these factors can affect breast cancer survival, no matter if a woman gets an annual mammogram or not.
If you're 40 or older and have an average risk of breast cancer, yearly screening mammograms should be part of your healthcare. If your breast cancer risk is higher than average, you should talk to your doctor about a more aggressive breast cancer screening plan that makes the most sense for your particular situation.
There's only one of you and you deserve the best care possible. Don't let any obstacles get in the way of your regular screening mammograms:
- If you're worried about cost, talk to your doctor, a local hospital social worker, or staff members at a mammogram center. Ask about free programs in your area.
- If you're having problems scheduling a mammogram, call the National Cancer Institute (800-4-CANCER) or the American College of Radiology (800-227-5463) to find certified mammogram providers near you.
- If you find mammograms painful, ask the mammography center staff members how the experience can be as easy and as comfortable as possible for you.
For more information, visit the Breastcancer.org Mammograms pages.