A new study has reported that use of beta blockers is associated with improved relapse-free survival in breast cancer patients, especially in those with triple negative (ER-/PR-/HER2-) breast cancer. Beta blockers are used to treat hypertension, abnormal heart rhythms, and heart failure. The study was designed to investigate the association between beta blocker intake, pathologic complete response rates, and survival in breast cancer patients treated with neoadjuvant chemotherapy (chemotherapy that took place before surgery to remove the tumor).
To conduct the study, the authors reviewed the medical records of 1,413 breast cancer patients who received chemotherapy before breast cancer surgery between 1995 and 2007. A total of 102 patients who used beta blockers at the start of chemotherapy were compared to 1,311 not taking any beta blockers. Women in the beta blocker group tended to be older and were more likely to be obese. Rates of pathologic complete response (no microscopic evidence of viable cancer cells in tumor specimens removed during surgery) were compared between the two groups. The results were adjusted for age at diagnosis, race, tumor stage, grade, hormone receptor status, lymphovascular invasion, body mass index, diabetes, hypertension, and angiotensin-converting enzyme (ACE) inhibitor use.
The rate of pathologic complete response was not found to differ significantly between the beta blocker group and the non-beta blocker group. Women using beta blockers were approximately twice as likely to survive without a breast cancer recurrence during the study period, but beta blockers did not appear to influence overall survival. Among the 377 patients with triple negative breast cancer, beta blocker intake was associated even more favorable relapse-free survival. Triple negative patients using beta blockers also were observed to have better overall survival, but this result did not reach statistical significance. The authors comment that additional studies are warranted to evaluate the potential benefits of beta blockers on breast cancer recurrence, especially in those with triple negative breast cancer.