Susan Dent, MD, Cardio-Oncology, Duke Cancer Institute, Durham, NC, discusses the impact of cardiovascular disease (CVD) and health care utilization (HCU) in patients with HR+, HER2 - advanced breast cancer receiving endocrine therapy.
 

Transcript:

Thank you for inviting me to talk about our poster that was recently presented at ESMO. My name is Dr. Susan Dent. I am a medical oncologist at Duke Cancer Institute in Durham, North Carolina. I'm also co-director of the Duke Cardio-Oncology program here at Duke University.

At this year's ESMO meeting 2021, we had the opportunity to present the results of our study looking at the cardiovascular risk factors and events in patients with advanced breast cancer who are prescribed endocrine therapy as well as CDK4/6 inhibitors.

We know that the addition of CDK4/6 inhibitors to endocrine therapy backbone for women and men improves clinical outcomes for our patients, leading to improvements in progression-free and overall survival.

But what we don't have a good appreciation for is the cardiovascular impact of these drugs on patients, particularly the CDK4/6 inhibitors.

What we set out to do was to look at a cohort of patients on endocrine therapy alone, versus endocrine and a CDK4/6 inhibitor. With the game, an idea of looking at cardiovascular risk factors, the development of cardiovascular disease while on these therapies, and importantly healthcare utilization.

This was a retrospective cohort study where we had two cohorts of patients. The first cohort looked at patients on endocrine therapy alone. The second cohort looked at patients on endocrine therapy backbone with a CDK4/6 inhibitor.

We presented the initial cardiovascular risk factors for these patients at San Antonio last year, which showed essentially that in these two cohorts of patients, numerically, there were similar baseline cardiovascular risk factors, whether you were prescribed endocrine therapy or endocrine therapy and a CDK4/6 inhibitor, with the exception that there's numerically a few more patients had hyperlipidemia in the the cohort that were prescribed endocrine therapy.

At this year's ESMO meeting, we updated our results to show that in the approximately 109 or so patients across both cohorts, that similar number of patients developed cardiovascular disease while they were on these medications numerically.

That there was a similar healthcare utilization, whether you were receiving endocrine therapy alone or endocrine therapy and the CDK4/6 inhibitor. That included ICU admissions, emergency room visits, and cardiac procedures.

Interestingly, we looked at ECG monitoring, which is something that you do or is warranted with certain of the CDK4/6 inhibitors. It was actually more ECG monitoring in the non-CDK4/6 cohort, which we found interesting.

But the reassuring thing, I think, about our poster, recognizing that this is a small study with a small cohort of patients, is that in this population where women were in their mid-60s in both cohorts, we did not see any extra signals to say that you were more likely to have cardiac event or experience more healthcare utilization when prescribed a CDK4/6 inhibitor.

Now, the caveats to this study are it's a small group from a small institution. I think we still have a lot more to learn. I think based on the results of our study what I would like to see is a larger cohort of patients that are looked at. Particularly I'd like to look at those patients who were on endocrine therapy alone versus endocrine therapy and a CDK4/6 inhibitor at the same period of time.

We looked. Cohort A in our study was 2012 to 2014. Cohort B, the CDK4/6 inhibitor and endocrine therapy, was 2015 to 2017. So, it would be interesting to look at a larger cohort in the same time period.

But overall I think even though the study was never set out to compare the two groups statistically, the data that we have is purely descriptive and the numbers that we have say that we're doing quite well in terms of treating these women with this newer class of drugs.

I think that's particularly important as we see survival rates increase in this patient population of women who are prescribed CDK4/6 inhibitors with an endocrine therapy background.