Major Finding: Aspirin use after the diagnosis of stage I-III breast cancer was associated with a multivariate adjusted relative risk of breast cancer death of 1.07 among those who used aspirin 1 day per week, 0.29 for those who used aspirin 2-5 days per week, and 0.36 for those who used aspirin 6-7 days per week.
Data Source: Responses from 4,164 female RNs in the Nurses' Health Study who were diagnosed with stage I-III breast cancer between 1976 and 2002. The women were observed until June 2006 or until they died, whichever came first.
Disclosures: Supported by a grant from the National Institutes of Health. The researchers indicated they had no conflicts of interest.
Aspirin use after the diagnosis of stage I-III breast cancer was associated with a decreased risk of breast cancer death and distant recurrence, results from the ongoing Nurses' Health Study demonstrated.
The study is believed to be the first to report a survival advantage among women with breast cancer who take aspirin.
“If confirmed, our results may broaden the scope of interventions available to reduce breast cancer–related death and mortality,” researchers led by Dr. Michelle D. Holmes of at Harvard Medical School and Harvard School of Public Health, Boston, reported.
They emphasized that the results “may be generalizable only to longer term breast cancer survivors,” described as those who have lived long enough after diagnosis to report aspirin use after diagnosis (about 4 years). “Fortunately, almost 90% of women diagnosed with breast cancer live at least 5 years. Thus, our findings have considerable clinical importance.”
For the study, the researchers drew from questionnaires to evaluate aspirin use among 4,164 female registered nurses in the Nurses' Health Study who were diagnosed with stage I, II, or III breast cancer between 1976 and 2002, and who were observed until they died or until June 2006, whichever came first (J. Clin. Oncol. 2010 Feb. 16 [doi:10.1200/JCO.2009.22.7918
Dr. Holmes and her associates reported that 314 deaths attributed to breast cancer and 400 distant recurrences occurred during the study period. Compared with women who never used aspirin, the multivariate adjusted relative risk of breast cancer death was 1.07 among those who used aspirin 1 day per week, 0.29 for those who used aspirin 2-5 days per week, and 0.36 for those who used aspirin 6-7 days per week. “Results did not differ appreciably when stratified by stage, [body mass index], menopausal status, or [estrogen receptor] status.”
Aspirin use had a similar impact on distant recurrence of cancer. Compared with women who never used aspirin, the multivariate adjusted relative risk of distant recurrence was 0.91 among those who used aspirin 1 day per week, 0.40 for those who used aspirin 2-5 days per week, and 0.57 for those who used aspirin 6-7 days per week.