Regular screenings for breast cancer have been shown to reduce mortality rates by 20%. However, some women, particularly those who are Black or Hispanic/Latinx, as well as those who are overweight or obese, are more likely to be diagnosed with advanced breast cancer despite regular screening. In a recent study published in JAMA Oncology, researchers from UC San Francisco found that regular screening alone may not be sufficient to prevent advanced breast cancer. Primary prevention efforts should also focus on helping overweight or obese women, especially women of color, achieve a normal weight.
Advanced breast cancer is classified as stage II or higher based on the American Joint Committee on Cancer prognostic pathologic stage. These are tumors that are large in size, have spread to lymph nodes, or exhibit other characteristics associated with poorer prognosis, such as being high-grade and estrogen receptor-negative. Treatment for advanced breast cancer typically involves surgery and systemic treatment, and early detection through screening can help prevent deaths from breast cancer.
Calculating the risk of advanced breast cancer in women who undergo regular screening can guide screening frequency and the use of supplemental imaging. Clinical risk factors associated with advanced breast cancer include high breast density, high body mass index (BMI), increasing age, family history of breast cancer in a first-degree relative, history of previous breast biopsies, and postmenopausal status.
Among women who undergo regular screenings, Black women have a two-fold higher rate of advanced breast cancer compared to White women.
To evaluate the population-attributable risk proportions (PARPs) for advanced breast cancer, which represents the proportion of advanced cancer incidence in the population attributed to a specific risk factor, the researchers conducted a cohort study using data from the Breast Cancer Surveillance Consortium (BCSC) from January 2005 to June 2018. The study included 904,615 women aged 40 to 74, who underwent a total of 3,331,740 annual or biennial screening mammograms. Within two years of the screening examinations, 1815 advanced breast cancer cases were diagnosed.
The study examined various risk factors, including breast density, family history of breast cancer, overweight/obesity (BMI>25), history of benign breast biopsy, and screening interval (biennial vs. annual), stratified by menopausal status and race/ethnicity (Asian or Pacific Islander, Black, Hispanic/Latinx, White, other/multiracial).
The PARPs for BMI were higher for postmenopausal women (30%) compared to premenopausal women (22%), with the highest rates observed in postmenopausal Black women (38.6%) and Hispanic/Latinx women (31.8%), as well as premenopausal Black women (30.3%). The prevalence of overweight/obesity was highest in premenopausal Black women (84.4%), postmenopausal Black women (85.1%), and Hispanic/Latinx women (72.4%).
Black and Hispanic/Latinx women have a higher risk of being diagnosed with advanced breast cancer compared to White, Asian, or Pacific Islander women. This difference is only partially explained by screening. Additional risk factors need to be identified to develop personalized and equitable screening strategies and primary prevention interventions.
Breast density PARPs were higher in premenopausal women (37%) compared to postmenopausal women (24%), with premenopausal White women having the highest rates (39.8%). Family history of breast cancer, history of breast biopsy, and screening interval had smaller PARPs for both premenopausal and postmenopausal women.
Among women who undergo regular screenings, the study found that screening frequency was a weak risk factor for advanced breast cancer. Screening biennially versus annually accounted for only a small proportion of advanced cancer diagnoses in the study population. Being overweight or obese accounted for the largest proportion of advanced cancers in postmenopausal women (30%), while dense breasts accounted for the largest proportion of advanced cancers in premenopausal women (37%).
This study is the first to calculate PARPs for advanced breast cancer. The researchers found that being overweight or obese is the primary risk factor for advanced breast cancer among postmenopausal Black and Hispanic/Latinx women. This finding is in contrast to previous studies that identified overweight/obesity as the main risk factor for invasive breast cancer in postmenopausal Black women, but not Hispanic/Latinx women.
According to lead author Karla Kerlikowske, patients need to be educated about the factors that contribute to the development of advanced breast cancer and the interventions that can modify these risk factors. Offering supplemental imaging with MRI or ultrasonography to women at high risk for advanced cancer could reduce the chances of a late-stage diagnosis.
Note:
Source: Coherent Market Insights, Public sources, Desk research
We have leveraged AI tools to mine information and compile it