Several large studies, including a review by the U.S. Preventive Services Task Force in 2009 and a study on the causes of death in the United Kingdom in 2013, have questioned the value of screening mammograms.
Doctors who question the value of mammograms say that while mammograms do save lives, for each breast cancer death prevented, three to four women are overdiagnosed. 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
False positive results from screening mammograms also have helped fuel the debate about the value of breast cancer screening. When a mammogram shows an abnormal area that looks like a cancer but turns out to be normal, it’s called a false positive. Ultimately the news is good: no breast cancer. But the suspicious area usually requires follow-up with more than one doctor, extra tests, and extra procedures, including a possible biopsy. There are psychological, physical, and economic costs that come with a false positive.
These studies and the resulting stories in the media have fueled an ongoing debate about the value of screening mammograms.
A study suggests that women who receive false-positive mammogram results may be more likely to put off their next scheduled mammogram.
The research was published online on Feb. 9, 2017 by the journal Cancer Epidemiology, Biomarkers & Prevention. Read the abstract of “Impact of a False-Positive Screening Mammogram on Subsequent Screening Behavior and Stage at Breast Cancer Diagnosis.”
To see how a false positive screening mammogram result affected women, the researchers looked at the records of women who received mammograms through a large healthcare organization in the Chicago area and who had not been diagnosed with breast cancer. The researchers looked at 741,150 screening mammograms from 261,767 women:
- 90,918 of the mammogram results were false positives (12.3%)
- 650,232 were true negative results (87.7%)
The researchers defined a delay in mammogram screening as any mammogram that was done more than 12 months after the particular mammogram the researchers chose.
Women who had a false positive result were more likely to delay their next mammogram:
- women with false positive results waited about 36 months to have their next mammogram
- women with true negative results waited about 13 months to have their next mammogram
This difference was statistically significant, which means that it was likely due to the difference in results and not just because of chance.
"This [the fact that having a false positive screening mammogram caused women to delay coming back for their next screen] suggests that we need to more actively encourage women who have a false positive result from a screening mammogram to adhere to routine screening mammography recommendations because it has been shown to reduce breast cancer mortality," said Firas Dabbous, Ph.D., of the Advocate Lutheran General Hospital. "It's a delicate balance. We want to detect tumors when they are present but we don't want to overburden women with a lot of false positives and a workup that is not needed."
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, including fear of a false positive, 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 on mammograms, visit the Breastcancer.org Mammograms page.