Are Beta-Blockers Useful In The Fight Against Breast Cancer?
Posted Jun 22 2011 11:20am
In a previous blog I discussed the results of a new study, which indicated that blood pressure medications alter the risk for breast cancer recurrence. While the ACE inhibitors increased the risk for recurrence, the beta-blockers decreased this risk and blunted the effect of the ACE inhibitors. Two new studies published in the Journal of Clinical Oncology continue to explore the possible cancer-fighting benefits of beta blockers.
In the first breast cancer study , researchers investigated the link between using beta blockers with breast cancer survival in patients treated with chemotherapy. For this study, breast cancer patients taking beta blockers (102 patients) were compared to patients not taking beta blockers (1,311 patients). Differences in overall survival and relapse-free survival were assessed. After making adjustments for multiple factors, use of beta blockers improved the chances of relapse-free survival by nearly 50%, but did not improve the chances of overall survival. The benefits were even greater in triple negative breast cancer patients. Triple negative breast cancer patients taking beta blockers showed a 70% increased chance of relapse-free survival.
The second breast cancer study compared the potential benefits of two different beta-blockers, propranolol (a beta 1 and beta 2 blocker) and atenolol (a beta 1 blocker). For this study, information on breast cancer stage and beta blocker use was collected and compared to women not taking a beta blocker. The results of this study showed that the beta 1 blocker, atenolol, had no effect on the risk of local tumor invasion nor on the risk of metastatic breast cancer. In contrast, women using propranolol were about 75% less likely to be diagnosed with local tumor invasion and about 80% less likely to have lymph node involvement or metastases. Additionally, breast cancer - specific mortality was reduced in propranolol users.
These two studies provide some interesting insight into the possible benefits of beta blockers in the fight against breast cancer. Beta blocker use improved the chances of relapse-free survival in all breast cancer patients, but this benefit was even better in triple negative breast cancer patients. Furthermore, these studies show that not all beta blockers are the same when it comes to the fight against breast cancer. It appears from the second study that beta blockers that work through the beta 2 pathway are more effective at reducing the breast cancer progression and improving survival than beta blockers that use the beta 1 pathway. These early studies show the possible usefulness of beta blockers in our fight against breast cancer.