Dense Breasts in Older Women are Associated with Heightened Breast Cancer Risk
New BCSC study finds that older women with dense breasts are at increased risk of invasive breast cancer
Breast density is a measure of the amount of fibrous or glandular tissue compared with fatty tissue, with less dense breasts containing more fat. Physicians have long recognized that women with denser breasts are at increased risk of invasive breast cancer, heightening the importance of mammography screenings. A paucity of data, however, established such a risk in women age 65 and older, and virtually no data existed for women age 75 and older.
A new study published in JAMA Network Open used data from 193,000 women age 65 and older from 1996-2012 Breast Cancer Surveillance Consortium (BCSC) to address this gap. The study estimated the 5-year cumulative incidence of invasive breast cancer by breast density and age groups. Cox proportional hazards models were fit to estimate the association of breast density with invasive breast cancer risk adjusting for family history, BCSC registry, race/ethnicity, body mass index (BMI), postmenopausal hormone therapy use, and benign breast disease for age groups 65 to 74 years and ≥75 years. The results suggest that risk of invasive breast cancer increases with the density of breast, and the relative increment in younger subgroup (65-74) is slightly higher than risk increase in women aged ≥75 years. As a modest risk factor for invasive breast cancer, breast density should be considered when weighing harms and benefits of continued screening mammography in older age.
Full text citation and Link: Advani SM, Zhu W, Demb J, Sprague BL, Onega T, Henderson LH, Buist DSM, Zhang D, Schousboe JT, Walter LC, Kerlikowske K, Miglioretti DL, Braithwaite D for the Breast Cancer Surveillance Consortium. Association of Breast Density With Breast Cancer Risk Among Women Aged 65 Years or Older by Age Group and Body Mass Index. JAMA Network Open. 2021;4(8):e2122810. https://doi.org/10.1001/jamanetworkopen.2021.22810 [Link to article]
Posted by: Dongyu Zhang