GREENVILLE, S.C. (WSPA)- October is Breast Cancer Awareness Month.

New targeted therapy shows promising results for some metastatic breast cancer patients.

As part of our “Ask the Expert”, in partnership with Bon Secours St. Francis 7NEWS Anchor Taylor Murray spoke with an oncologist about the groundbreaking treatment.

When a patient receives a breast cancer diagnosis, their pathology report includes details about the specific type of cancer cells present.

“One of the first things we look for is expression of certain proteins on the surface of breast cancer cells. Some of those are hormone-mediated, like estrogen or progesterone, but there is one called HER2 that’s actually a growth protein that can actually result in these cancer cells. Basically, it’s a way that they are signaled to grow quicker,” Dr. Dyer said.

Dr. Steven Dyer, an oncologist, says 50 to 60 percent of breast cancers fit under this new diagnosis– HER2-low.

“So traditionally, HER2 was thought about as being binary, It was either positive or negative. But, what we found is that it actually, instead of being positive or negative, it actually exists on a continuum, a spectrum,” Dr. Dyer said.

This newly discovered classification is spurring changes in how breast cancer is treated.

In August 2022, The FDA approved targeted therapy for patients with HER2-low breast cancer.

“It’s a kind of medicine called an antibody-drug conjugate or ADC. Those are not new. They’ve been around for several years, actually. But, this particular one has a component of it that targets the HER2 receptor specifically, and that’s attached to a chemotherapy component.”

Dr. Steven Dyer, Oncologist, Bon Secours St. Francis

It’s a lifesaving treatment that until now millions of breast cancer patients have been ineligible for.

Targeted therapy tends to have fewer side effects than traditional chemotherapy.

“The problem with chemotherapy, as you know, is that the side effects can sometimes be very damaging, not just to the cancer but to the patient. So, what this allows is for that HER2 to sort of serve as the homing device… and that takes it directly to the cell where you can deliver chemotherapy to that cancer cell while sparing a lot of the normal tissues,” Dr. Dyer said.

If you have metastatic breast cancer or are experiencing a recurrence, health experts are now recommending patients ask their care team to retest to verify their HER2 status.

Results of trials showed targeted therapy reduced the risk of death and increased overall survival by more than 6 months vs. traditional chemotherapy.

Bon Secours Saint Francis Cancer Center is taking part in some of these groundbreaking trials. Click here for more information.

Click here to submit a health topic for our Ask the Expert series.