Aspirin May Lower Breast Tissue Density, Lead to Early Detection of Cancer

New data does not support the idea that aspirin has protective qualities and “down-the-road” benefits for breast cancer patients. It may, however, help reduce breast density and improve earlier detection of some breast cancers.

Aspirin does not appear to be protective or associated with improved clinical outcomes or survival among breast cancer patients with aggressive disease, but it may help reduce breast tissue density and thus lead to earlier detection of some breast cancers, according to 2 recent studies presented at the 2015 San Antonio Breast Cancer Symposium.

Researchers led by Julia C. Tchou, MD, PhD, of the Perelman School of Medicine at the University of Pennsylvania, reported that a history of taking aspirin was not associated with improved survival regardless of receptor status (patients included those with receptor-positive, HER2-positive, and triple-negative cancers). After a 5-year follow-up, researchers actually found that low-dose aspirin was significantly associated with worse overall survival compared with patients who didn’t take it before diagnosis.

The investigators followed 1000 patients diagnosed with breast cancers among whom 14% had a history of aspirin use for at least 30 days prior to diagnosis. The investigators said larger patient cohort studies are needed to confirm these results.

A second study presented at the symposium examined whether aspirin is associated with breast density. Despina Kontos, PhD, and colleagues at the University of Pennsylvania, examined the medical records of 26,000 women who had undergone routine screening mammography during 2012 and 2013 and had an outpatient visit with a doctor within the previous year that included a recorded list of medications used.

They report an inverse association between aspirin use and mammographic density. Compared with women with extremely dense breasts, women with fatty or less dense breasts were more likely to be aspirin users. Investigators also found a lower likelihood of having extremely dense breasts with increasing aspirin dose. This association was significant among women under age 60 and among African American women.