Dr Debra Patt Discusses the Paradigm Shift of Treating HER2-Low Breast Cancer

Previously, patients with low expression of HER2 were categorized as HER2-negative but adding the HER2-low classification creates new opportunities for patients with advanced breast cancer, explained Debra Patt, MD, PhD, MBA, executive vice president of Texas Oncology.

Transcript

How does adding the definition of HER2-low change and improve how care will be delivered to patients?

So, when we watch the DESTINY-Breast04 for data presented at ASCO, it was such a wonderful moment for breast cancer specialists. We really saw a paradigm shift from patients being HER2-positive and -negative to HER2-positive, HER2-low, and HER2-negative. And that paradigm shift is newly present, because we realize that among the HER2-low patient population that was previously all categorized as HER2-negative. And by that, I mean the IHC1+ [immunohistochemistry] and IHC2+, FISH [fluorescence in situ hybridization]–negative patient population of advanced breast cancers. We know that by having an appreciation for this new designation of HER2-low that when we give patients the opportunity to be treated with trastuzumab deruxtecan in comparison to chemotherapy that there is a progression-free and overall survival benefit to that treatment.

And so, it helps patients to have this new paradigm and to have this new way of classifying advanced breast cancer patients. Even more so, it is a not a small component of advanced breast cancer patients; we would estimate about 55% of advanced breast cancer patients are characterized as HER2-low. And so, this is a real, new opportunity for the patients that we serve with advanced breast cancer.