Positive survival association with statins and triple-negative breast cancer

September 2021 Clinical Practice Tobias Rawson

A retrospective analysis of survival outcomes in breast cancer patients who were started on statins up to 12 months post-diagnosis has concluded that there is a positive, statistical association between the use of statins and survival outcomes in triple-negative breast cancer (TNBC). These findings are particularly important given the need for treatment options in this aggressive BC subtype. Additionally, this could represent a cost-effective therapy option, given how cheap and prevalent the prescribing of statins are worldwide.

Kevin Nead, M.D, an assistant professor of Epidemiology and co-author from The University of Texas MD Anderson Cancer Center explained that “there is already a body of literature on statins and breast cancer and the results have been inconsistent. Previous research has looked at breast cancer as only one disease, but we know there are many subtypes of breast cancer and we wanted to focus our research on this particularly aggressive form of breast cancer that has limited effective treatment options.”

The study collected data from the Surveillance, Epidemiology, and End Results-Medicare and Texas Cancer Registry-Medicare databases. Eligible patients were women over the age of 66 who had stage I, II or III breast cancer. Multivariable Cox proportional hazard regression models were used to identify an association between new statin use in the 12 months after breast cancer diagnosis in terms of overall survival (OS) and breast cancer-specific survival (BCSS).

58% improvement in BCSS with statins

The study included data from 23, 192 women, 2, 281 of which were incidental statin users. 78.1% of statin users were white, 8.9% of afro-Caribbean descent and 8.4% were Hispanic. At a median follow-up of 3.3 years for BCSS and 4.4 years for OS, researchers found a 58% improvement in BCSS (HR[95%CI]: 0.42[0.20-0.88], P= 0.022) and a 30% improvement in OS (HR[95%CI]: 0.70[0.50-0.99], P= 0.046) in TNBC patients who started statin therapy within 12 months of their cancer diagnosis (N= 1534). Interestingly, these findings were not observed in BC patients who did not have TNBC (N= 15, 979) (BCSS HR[95%CI]: 0.99[0.71-1.39], P= 0.97), (OS HR[95%CI]: 1.04[0.92-1.17], P= 0.55). Additionally, this association was found to be greater in earlier stages of TNBC. High-intensity statin use, and lipophilic statins (L-statins) were also associated with improved overall survival. Although these are encouraging results, ultimately these findings need to be validated in a prospective, randomised trial.

“We know that statins decrease breast cancer cell division and increase cell death,” says Nead. “Our study shows that there is an association between statins and improved outcomes in TNBC, and it is time to pursue this idea further in a prospective trial.”

Reference:

Nowakowska MK, Lei X, Thompson MT et al., Association of statin use with clinical outcomes in patients with triple-negative breast cancer. Cancer. 2021; published online ahead of inclusion in an issue.