RSNA 2018: Breast Cancer Risk-Based Mammography Screening in Younger Women
A new, large-scale study of more than 5 million mammograms found that annual mammography screening beginning at age 30 may benefit women with at least 1 of 3 specific risk factors: dense breasts, a personal history of breast cancer, or a family history of breast cancer. The study was presented at the Annual Meeting of the Radiological Society of North America (RSNA) (Abstract SSM02-02).
“Women under 40 have not been the focus of our attention when it comes to breast cancer screening,” said Cindy S. Lee, MD, Assistant Professor of Radiology at New York University Langone Health, in a statement. “Everyone is talking about the 40 to 49 range, and not the 30 to 39 age range. It's difficult to study this group because most women in this age range do not get mammograms, but some of these young women have increased risk for breast cancer and may need earlier and/or supplemental screening.”
Study Methods
Dr. Lee and colleagues compared the performance metrics of screening mammography in women between the ages of 30 and 39 years with 3 specific risk factors vs women between the ages of 40 and 49 years without these risk factors, using data from the National Mammography Database (NMD), the largest source of screening mammography outcomes in the United States. The NMD contains information from over 19 million mammograms, including self-reported patient demographics, clinical findings, mammography interpretations, and biopsy results.
The researchers analyzed data from over 5.7 million screening mammograms performed on more than 2.6 million women between January 2008 and December 2015 in 150 facilities across 31 states in the United States. The research team compared screening performance metrics among subgroups of women based on age, risk factors, and breast density.
Three specific risk factors for breast cancer were evaluated in this study: family history of breast cancer (any first-degree relative regardless of age), personal history of breast cancer, and dense breasts.
“Current breast risk prediction models incorporate different risk factors, which are weighed differently and can produce different results for the same patient. This complexity can lead to confusion and uncertainty for both doctors and patients,” Dr. Lee said. “Our study defined ‘increased breast cancer risk’ in a simpler and more inclusive way. Any woman with dense breasts, personal history, or family history of breast cancer in any first-degree relative is considered to have increased risk.” She added that breast density is an important risk factor for breast cancer but is excluded from all risk models except one.
Four performance metrics for screening mammography were calculated for each patient age and risk group: cancer detection rate, recall rate, positive predictive value for biopsy recommended, and positive predictive value for biopsy performed.
Major Findings
In the under-40 age group, some of the women had increased risk either because of dense breasts, family history, or a personal history of breast cancer.
Overall, women aged 30–34 and 35–39 had similar cancer detection rates, recall rates, and positive predictive values. Cancer detection rates were significantly higher in women with at least 1 of the 3 evaluated risk factors. Moreover, compared to women aged 40 to 44 at average risk, incidence screening (at least 1 prior screening examination) of women in their 30s with at least 1 of the 3 evaluated risk factors showed similar cancer detection rates and recall rates.
“Women with at least 1 of these 3 risk factors may benefit from screening mammography beginning at age 30, instead of 40,” Dr. Lee advised.
Disclosure: Dr. Lee reported no conflicts of interest.
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.
