There are few things more terrifying for a woman than a breast cancer scare. A suspicious or “false positive” mammogram signaling to a woman that there’s a chance she could have a malignant tumor is traumatic enough that many studies have found that women follow their doctor’s screening recommendations more closely afterwards. However, a new study from Chicago researchers seems to suggest otherwise.
It seems like common sense that, following a cancer scare, one would be more cautious and proactive about their health. False positive experiences often cause anxiety and worry, which eventually fade into relief and prompt women to return for more frequent mammograms. Firas M. Dabbous, an epidemiologist and researcher at Advocate Lutheran General Hospital near Chicago, sought to challenge that assumption with his study analyzing more than 741,000 mammograms of 261,767 women taken between 2001 and 2014, excluding women whose mammograms accurately detected cancer. Of the sample, roughly 12 percent of the x-rays were false positives, which is just over the industry benchmark of 10 percent.
The results of the study, while not entirely conclusive, were surprising. The researchers found that 22 percent of women with false positives and 15 percent with true negative mammograms did not return for further mammograms. When adjusted for age, race, and other factors that could influence results, it found that 19 percent of women with true negatives didn’t come back, so the difference was more marginal. In addition, the study found that women with false positives were slower to return for their annual mammograms when compared to women with true negatives, taking a median of 25 months to return as opposed to 15 (or 18 months when adjusting for age and race factors).
One major factor that could affect the accuracy of this study is the fact that the medical community is divided over screening guidelines. While regular breast exams have been shown to reduce breast cancer deaths by 15 to 20 percent, guidelines for the age a woman should start to get annual screenings varies. The main guideline advises women to start at age 40, while the U.S. Preventative Services Task Force has, since 2009, recommended mammograms every other year beginning at age 50.
The study did, however, address the fact that many women with false positives exhibit certain traits that would make their mammograms more difficult to interpret and lead to the false results. For instance, they tend to be younger, premenopausal, and more likely to be experiencing their first screening and therefore lacking a previous mammogram for comparison. Women with false positives are also more likely to be black and have larger breasts.
Despite some inconsistencies affecting the study, leaders in the medical community are optimistic about the potential implications it could present. According to Emily Conant, chief of breast imaging at the University of Pennsylvania, “All in all, it’s a strong study that suggests an area for improvement, both for healthcare providers and radiologists, in communicating results to patients and discussing their approach to screening.”