The result would then be used to stratify further screening, with annual screening starting at age 40 for average-risk women who have dense breasts, and screening every 2 years starting at age 50 for women without dense breasts.
Such an approach would be cost effective and offers a more targeted risk-based strategy for the early detection of breast cancer when compared with current practices, say the authors, led by Tina Shih, PhD, University of Texas MD Anderson Cancer Center, Houston.
Their modeling study was published online in the Annals of Internal Medicine.
However, experts writing in an accompanying editorial are not persuaded. Karla Kerlikowske, MD, and Kirsten Bibbins-Domingo, MD, PhD, both from the University of California, San Francisco, point out that not all women with dense breasts are at increased risk for breast cancer. They caution against relying on breast density alone when determining screening strategies, and say age and other risk factors also need to be considered.
New approach proposed
Current recommendations from the United States Preventive Services Task Force suggest that women in their 40s can choose to undergo screening mammography based on their own personal preference, Dr. Shih explained in an interview.
However, these recommendations do not take into consideration the additional risk that breast density confers on breast cancer risk – and the only way women can know their breast density is to have a mammogram. “If you follow [current] guidelines, you would not know about your breast density until the age of 45 or 50,” she commented.
“But what if you knew about breast density earlier on and then acted on it –would that make a difference?” This was the question her team set out to explore.
For their study, the authors defined women with dense breasts as those with the Breast Imaging Reporting and Data System (BI-RADS) category C (heterogeneously dense breasts) and category D (extremely dense breasts).
The team used a computer model to compare seven different breast screening strategies:
- No screening.
- Triennial mammography from age 50 to 75 years (T50).
- Biennial mammography from age 50 to 75 years (B50).
- Stratified annual mammography from age 50 to 75 for women with dense breasts at age 50, and triennial. screening from age 50 to 75 for women without dense breasts at the age of 50 (SA50T50).
- Stratified annual mammography from age 50 to 75 for women with dense breasts at age 50, and biennial screening from age 50 to 75 for those without dense breast at age 50 (SA50B50).
- Stratified annual mammography from age 40 to 75 for women with dense breasts at age 49, and triennial screening from age 50 to 75 for those without dense breasts at age 40 (SA40T50).
- Stratified annual mammography from age 40 to 75 for women with dense breasts at age 40, and biennial mammography for women from age 50 to 75 without dense breasts at age 40 (SA40B50).
