New Frontiers in Breast Cancer: Updates and Advances in Treatment - Episode 6

Selecting Novel Adjuvant Therapy For Patients With Breast Cancer


Following their discussion on the OlympiA and monarchE trials in breast cancer, experts consider when they would use olaparib or abemaciclib in the adjuvant setting.


Joyce A. O’Shaughnessy, MD: Sarah, here’s a tough question for you. For a young woman, 14 positive nodes despite preoperative chemotherapy, you’re going to optimize her endocrine therapy. But let’s say she’s a germline BRCA2, and you’ve got a choice for the patient. How are you thinking through abemaciclib versus olaparib for a patient who is eligible for both trials?

Sara A. Hurvitz, MD: When the BRCA mutation is there, I tend to feel that the PARP inhibitor is the one to be prioritized. Now that we have overall survival data, that underscores that thinking. Believe it or not, I thought this was one of those hypotheticals I would never see in practice, but I’ve had 3 patients in the last 6 months who fall into this category. I have used olaparib first, with the plan to utilize abemaciclib after, even though we’re not following the monarchE and starting the abemaciclib on time. I feel that if it’s beneficial and there’s micrometastatic disease to be managed, then using it after should theoretically still work. In those very high-risk patients who have both a BRCA2 mutation and qualify for abemaciclib, I’m doing PARP inhibitor first followed by abemaciclib, with the caveat that this has not been tested in a clinical trial. It’s the art of medicine. I’m definitely not using the 2 drugs together, of course, which is really important for people to know.

Joyce A. O’Shaughnessy, MD: Yes, because the OlympiA trial was a very substantial improvement, 8.8% in IDFS [invasive disease-free survival], but unfortunately, there was still recurrences. There were still recurrences in these patients, and some of this breast cancer can be ER [estrogen receptor]-driven even though its germline BRCA. The CDK4/6 inhibitors can also potentially be used. But I totally agree, given the choice between the two, I am also prioritizing the PARP inhibitor for the germline BRCA patients whose breast cancer is HR [hormone receptor]-positive. The exquisite synthetic lethality with a PARP inhibitor in the context of a germline mutation is one of the most effective things we’ve got in all of breast cancer. I also agree that the survival data are critically important that have come out from the OlympiA trial. I’m also prioritizing that as my first go-to for these high-risk patients.

Transcript edited for clarity.