Reduced Risk of Breast Cancer Recurrence in Patients Using ACE Inhibitors, ARBs, and/or Statins

Background: Epidemiologic and biochemical evidence suggest a role of statins and angiotensin-converting enzyme (ACE) inhibitors or angiotensin-receptor blockers (ARBs) as anti-neoplastic agents. This study was designed to evaluate the association between the use of these agents and the risk of breast cancer recurrence. Methods: We reviewed the medical records of patients treated for stage II/III breast cancer between 1999 and 2005. Statin and ACE-inhibitors/ARB users were defined as patients who took these medications for at least 6 months in no evidence of disease (NED) stage after the initial diagnosis. The primary outcome was disease-free survival and the secondary was overall survival. The Kaplan-Meier and Cox proportional hazard models were used. Results: A total of 703 patients were included. The median and maximal of follow up was 55 and 118 months, respectively. A total of 168 patients used ACE-inhibitors/ARBs, 156 patients used statins, and 81 used both. Univariate analysis showed significant reduction in breast cancer recurrence among patients who used ACE-inhibitors/ARBs (hazard ratio (HR)=0.57; 95% CI: 0.37-0.89; p=.013) or statins (HR=0.43; 95% CI: 0.26-0.70; p<.001). After adjusting for multiple variables, the use of ACE-inhibitors/ARBs (HR=0.49; 95% CI: 0.31-0.76; p=.002) and statins (HR=0.40; 95% CI: 0.24-0.67; p<.001) remained significant and an additive effect was found on those who used both drugs (HR=0.30 95% CI: 0.15-0.61; p=.001). No association was found regarding overall survival. Conclusions: The use of ACE-inhibitors/ARBs, statins, and the combination of both were all associated with a reduced risk of breast cancer recurrence. This observation should prompt further exploration.