A recent study published online in the Journal of the American Medical Association suggests that daily aspirin use does not improve the risk of breast cancer recurrence or survival among participants with high-risk nonmetastatic breast cancer.

Conducted by Wendy Y. Chen, M.D., from the Dana-Farber Cancer Institute in Boston, and colleagues, the study aimed to evaluate whether aspirin reduces the risk of invasive cancer events among survivors of breast cancer. The analysis included 3,020 participants enrolled at 534 sites between January 6, 2017, and December 4, 2020, with follow-up until March 4, 2023.

The researchers reported that the Alliance Data and Safety Monitoring Committee recommended suspending the study at the first interim analysis due to the hazard ratio crossing the prespecified futility boundary. At a median follow-up of 33.8 months, 253 invasive disease-free survival events occurred, with 141 in the aspirin group and 112 in the placebo group, resulting in a hazard ratio of 1.27 (95% confidence interval [CI], 0.99 to 1.63; P = 0.06).

Furthermore, the aspirin group exhibited higher numbers of all-invasive, disease-free survival events, including death, invasive progression (both distant and locoregional), and new primary events, although the differences were not statistically significant. Overall survival also showed no difference between the groups (hazard ratio, 1.19; 95% CI, 0.82 to 1.72). Additionally, both groups had similar rates of adverse events in grades 3 and 4.

Despite its widespread availability and initial promise, aspirin should not be recommended as an adjuvant breast cancer treatment, according to the authors. 

These findings provide valuable insights into the effectiveness of aspirin as a potential adjuvant therapy for breast cancer and highlight the need for continued research to identify alternative treatment options for high-risk breast cancer patients.