Educated Patient® Breast Cancer Summit at MBCC Early-Stage HER2-Positive Presentation: March 4, 2023

Knowing whether patients with early-stage breast cancer have HER2-positive disease allows them to receive the appropriate treatment for an aggressive type of cancer, an expert explained.

Early-stage HER2-positive breast cancer typically includes stages 1, 2A, 2B and 3A, and treatment is focused on achieving cure, unlike in later-stage disease.

“When someone has early-stage breast cancer, we basically consider that any breast cancer that is confined to the breast, the lymph nodes in the armpit and surrounding area,” Dr. Naomi Dempsey, breast medical oncologist at Miami Cancer Institute, Baptist Health South Florida, in Plantation, Florida, said in an interview with CURE®. “An advanced breast cancer is one that spreads to other places (of the body) such as the bones, the lungs, the liver, the brain.”

Although there are many treatments available for both settings, treatments for early-stage, HER2-positive breast cancer aim to cure the disease, whereas options for later-stage disease are more meant to treat the disease rather than cure it, according to her presentation at the CURE® Educated Patient® Breast Cancer Summit, held live and virtually at the Miami Breast Cancer Conference.

“(With early-stage HER2-positive breast cancer), we’re really thinking about staying on time and making sure that your treatments are not late or delayed,” Dempsey told CURE®. “We do push a little harder when it comes to earlier-stage disease because we are trying to achieve a cure.”

Treatments Based on HER2-Positive Breast Cancer Stage

Treating stage 1 HER2-positive breast cancer typically starts with surgery followed by chemotherapy and Herceptin (trastuzumab), Dempsey explained. If needed, radiation may be added after chemo, and endocrine therapy is used in patients with HR-positive disease.

Patients with stage 2 or 3 HER2-positive breast cancer are initially treated with chemotherapy, Herceptin and Perjeta (pertuzumab), and then undergo surgery afterwards. Further treatment after surgery depends on how a patient responds to the therapies received before surgery, according to the presentation.

Dempsey noted HER2-positive breast cancer is a more aggressive type of breast cancer, and it requires chemotherapy for any tumor bigger than a half centimeter, or the size of a pencil eraser.

“We’re giving chemotherapy, and certainly some patients say, ‘My tumor is tiny. Do I really need chemotherapy?’ But when it comes to HER2-positive breast cancer, the answer is yes,” she explained. “We saw in the past, before we had really good treatments for HER2-positive breast cancer, outcomes were really not what we were wanting to see. We weren’t getting the cure rates that we were getting in other types of breast cancers.”

She added that giving more aggressive treatment to patients with early stage HER2-positive breast cancer allows cancer care teams to bring the outcomes to levels that are seen in other breast cancer subtypes.

Ongoing Research in HER2-Positive Breast Cancer

Much research has been done to determine how much treatment is needed to improve outcomes in early-stage HER2-positive breast cancer. Since these outcomes are achieved with more aggressive treatments, researchers are focusing on whether patients with stage 1 cancer, for example, are being overtreated.

“Right now, some of what we’re thinking about, particularly in stage 1 breast cancers that are only in the breast, the size of about a cranberry or smaller, … maybe we’re overtreating some of these patients,” Dempsey said. “We’re getting great outcomes, but we’re wondering, do you really need to lose your hair or have the risk of permanent neuropathy? Can we do less toxic treatment and still have the great outcomes that we’ve been seeing in recent years?”

One trial that is being conducted at Dempsey’s institution aims to determine whether less treatment can result in similar outcomes in patients with early-stage HER2-positive breast cancer.

“Doing less basically means that instead of receiving a strong chemotherapy that would cause a patient with stage 1 HER2-positive breast cancer to lose (their) hair, we are giving a medication called Kadcyla (ado-trastuzumab emtansine), that is like a smart bomb,” Dempsey said. “It’s a HER2-directed therapy, so it's bringing chemotherapy only to HER2-positive cells.

Patients randomly assigned treatment with Kadcyla will be compared with patients assigned to receive a standard chemotherapy regimen to see which group has a better side effect profile and outcomes.

Advice for Patients With Early-Stage Breast Cancer

Dempsey highlighted the importance of working with a multidisciplinary team when receiving care for early-stage HER2-positive breast cancer. This includes a surgeon, a medical oncologist, a radiation oncologist, if needed, and a nurse navigator or social worker.

“Nobody cures early-stage breast cancer by themselves, and we all really need a team,” she said. “So make sure that your team is communicating regularly. They're discussing your case, everybody is really working together. This is vital to getting the excellent outcomes that that we've been seeing in recent years in HER2-positive breast cancer.”

She also urged patients to undergo HER2 testing to determine their status.

“Knowing what is HER2 and whether or not you are HER2-positive is important because it will really change your treatment,” Dempsey said. “Ask your oncologist what testing has been done to determine HER2 status, and what does HER2 mean. Then from there, we really are able to create a very personalized treatment plan for you based on stage, HER2 status, hormone status and personal preferences.”

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