Alert for Women With Breast Cancer: What The Amazing New Findings About The Drug Enhertu Mean For You & What To Ask Your Doctor

However, before we get to that, let's break down what this study was able to find out.

Related: A 'New' Type Of Breast Cancer? Practice-Changing Results? New Study Says Yes, And Provides Hope For Patients With HER2 'Low' Breast Cancer

Research Breakdown & Findings

The new study, which was published in The New England Journal of Medicine, found that the experimental drug trastuzumab deruxtecan (brand name: Enhertu), "resulted in significantly longer progression-free and overall survival than the physician's choice of chemotherapy" for patients with metastatic breast cancer. (Metastatic disease is when the cancer has spread to other parts of the body than where it originated.)

Related: Stage Four Breast Cancer

"The reason why it (the study) got so much attention is because of the improvement in overall survival," Dr. Elizabeth Comen, a breast oncologist at Memorial Sloan Kettering Cancer Center (MSK) in New York City and SurvivorNet medical advisor, told us about this research, "which is hard to do in metastatic breast cancer patients."

More specifically, the trial reported on the use of Enhertu in women with metastatic hormone receptor-positive or negative, HER2-"low" breast cancer, who had received multiple prior lines of treatment.

It's worth noting that Enhertu is designed to target HER2, a protein that promotes the growth of cancer cells. Trial researchers analyzed more than 500 patients with metastatic disease who were categorized as HER2-low (having few HER2 cells).

Enhertu had previously shown success in women with HER2-positive breast cancer, but validation in the newly defined HER2-"low" cohort hadn't been established in a large study. What this means is that in patients who had HER2-positive tumors, the drug Enhertu had shown success, but it was unknown what would happen in patients with only minor HER2 expression that being, the HER2-"low" group.

Right now, Enhertu is only approved by the U.S. Food and Drug Administration to treat metastatic HER2-positive breast cancer and HER2-positive advanced stomach cancer.

Dr. Comen, during an on-air interview with NewsNation, gave us all a "two-minute biology lesson" to explain why the results of this study are considered especially remarkable.

"On the outside of our cancer cells, we have something called the HER2 receptor. Some breast cancer patients have it and some don't. Historically, we classified breast cancer patients as either HER2-positive, so they have a lot of it, or HER2-negative," she explained.

"What we've since learned is that some of these … patients that we thought were HER2-negative were actually HER2-low," Dr. Comen continued. "So, they had a little bit of this HER2 receptor, which means that in this trial, that they actually responded to targeted medications a specific medication called (trastuzumab deruxtecan), or Enhertu that targets the HER2 receptor, goes into the cancer cell and kills it. … In turn, as we see, improves outcomes for breast cancer patients helping them live longer, and hopefully better."

What Breast Cancer Patients Should Ask Their Doctors

Now that you’re armed with a solid understanding of this study, here’s what else you need to know.

This study is especially important for women who are actively receiving treatment, and according to Dr. Comen, there are some important questions you should be asking your doctor during your next visit.

First, it's so important that patients have their pathology report and understand, to the best of their ability, what it means, what kind of breast cancer they have and what stage their disease has reached.

Here's what you should be asking your doctor:

• Ask if your disease is actually considered HER2-low.
• If it's unknown, ask if you need another biopsy to determine the true nature of your breast cancer.
• Then, “Is Enhertu a drug I'm eligible to receive?”

Contributing: Dr. James Taylor

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