The issue of when to start and how often to get a mammogram has been a topic of fierce debate in recent years. In 2009, the U.S. Preventive Services Task Force (USPSTF) recommended that breast cancer screening should start at age 50 instead of 40 and that mammograms should be done every other year instead of every year.
Several medical organizations and advocacy groups, including the American Cancer Society and Breastcancer.org, didn’t agree with these USPSTF conclusions and ignored the recommendations. The recommendations were very controversial and were not widely adopted by doctors.
A new study suggests that women ages 50 to 74 have the same risk of being diagnosed with advanced-stage breast cancer whether they have a mammogram every year or every other year. Having dense breasts or using hormone replacement therapy (HRT) didn’t affect the results. But women ages 40 to 49 with very dense breasts were MORE LIKELY to be diagnosed with advanced-stage breast cancer if they had mammograms every other year instead of every year.
The study didn’t look to see if more early-stage cancers were found with annual screening. The study also didn’t look at women older than 74. Another USPSTF recommendation was to not encourage women age 75 and older to get mammograms because they might not benefit from the screenings.
The study was published online on March 18, 2013 by JAMA Internal Medicine. Read the abstract of “Outcomes of Screening Mammography by Frequency, Breast Density, and Postmenopausal Hormone Therapy."
Because the USPSTF recommendations sparked so much discussion, the researchers decided to look at the benefits and risks of getting screening mammograms every year compared to every other year, based on a woman’s age, breast density, and HRT use.
The researchers looked at information that was collected from January 1994 to December 2008 at mammography facilities that participate in the Breast Cancer Surveillance Consortium, a network of seven mammography registries funded by the National Cancer Institute. The researchers had information on 11,474 women diagnosed with breast cancer and 922,624 who weren’t diagnosed with breast cancer.
Women ages 40 to 49 with very dense breasts – about 12% to 15% of the women in that age group – had a higher risk of being diagnosed with advanced-stage breast cancer if they got screening mammograms every other year instead of every year.
While women ages 50 to 74 had the same risk of being diagnosed with advanced-stage breast cancer whether they had a mammogram every year or every other year – even if they had dense breasts or used HRT – the researchers didn’t look to see if more early-stage breast cancers were found if a woman had a mammogram every year. Diagnosing breast cancer early is important – early-stage cancer is more treatable than advanced-stage cancer.
The study also didn’t mention the reality that fewer women are getting mammograms. Until 2010, screening mammogram rates had been steadily going up about 1.4% per year since 2001. But for women on Medicare, there was a 4.3% drop in screening mammogram rates in 2010. The reality is that only about 50% of women are getting regular mammograms.
The researchers found that women who had annual mammograms were more likely to have a false positive – an abnormal area that looks like cancer but turns out to be normal. Ultimately, the news is good: no breast cancer. But the suspicious area usually requires follow-up with one or more doctors, extra tests, and extra procedures – possibly including a biopsy – not to mention the stress and worry about the results. There are psychological, physical, and economic costs that come with a false positive.
Still, according to Marisa Weiss, M.D., president and founder of Breastcancer.org, and Emily Conant, chief of breast imaging at the Hospital of the University of Pennsylvania, it’s important to know that if you routinely get screening mammograms, the number of false positives you get may go down because the radiologist is able to compare the current mammogram to earlier studies. This makes it easier to figure out if the finding on the mammogram is new, old, the same, or different. Cancer usually appears new and bigger when compared to an older mammogram.
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 or you have very dense breasts, you may want to 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.