Understanding HER2-Positive Breast Cancer
- Amelia Bayer, 30, from Virginia, was diagnosed with metastatic HER2-positive breast cancer after mistaking persistent pain and fatigue for workout strain. Now 31, she shares her story while undergoing ongoing immunotherapy to raise awareness and encourage others to listen to their bodies.
- HER2-positive breast cancer cells that have receptors for either estrogen or progesterone — or both — are considered hormone receptor positive. These hormones can help fuel the growth of cancer cells.
- “[HER2-positive breast cancer] can be very responsive to what we call targeted antibody therapies,” medical oncologist Dr. Elizabeth Comen at Memorial Sloan Kettering Cancer Center explains.
- “This HER2 receptor sits on the outside of the cell, but there are ways that we can actually block the ability of that HER2 receptor to stimulate the cell from growing,” Dr. Comen added.
- Some drugs that help treat HER-positive breast cancer include: trastuzumab (brand name: Herceptin), pertuzumab (brand name: Perjeta), and ado-trastuzumab emtansine (brand name: Kadcyla) that specifically target HER2+ cells, inhibiting their growth and reducing the risk of recurrence.
HER2-positive breast cancer gets its name because the cancer cells have too much of a protein called HER2, which stands for the human epidermal growth factor receptor 2. This type of cancer tends to grow faster, spread more easily, and come back more often. However, the good news is that it usually responds well to treatments that target the HER2 protein, like the antibody-drug conjugate Enhertu.
Read More@ameliasfight #cancertok #breastcancerin30s #chronicillness #stage4cancer #cancersymptoms
Bayer recalled that while training for a half-marathon at 29, in 2024, she noticed heavy legs, slow recovery after workouts, and a sharp shoulder pain during yoga.
She assumed it was overuse and continued with physical therapy.
However, her fatigue persisted, and a new sternum pain appeared, which she attributed to workout strain and her long-standing struggle with endometriosis.
More On Treatment For HER2-Positive Breast Cancer
- HER2-Positive Metastatic Breast Cancer Treatment Options Explained
- Do You Have HER2-Positive Metastatic Breast Cancer? Here’s A Breakdown Of Some Of Your Treatment Options
- The Drug Combo That Can Keep Advanced HER2-Positive Breast Cancer Under Control For Longer: Understanding The New Data
- When to Order Immunohistochemistry Testing: With Tailored Therapies for HER2-Positive Cancers, IHC is More Relevant for More Patients
- Treatment for HER2-Positive Breast Cancer
- New FDA Approved Drug Combo Offers HER2-Positive Metastatic Breast Cancer Patients Hope
In February 2025, severe chest pain landed Bayer in the hospital, where an ultrasound revealed a mass on her liver.
Tests later confirmed it was adenocarcinoma, with breast cancer suspected as the source. Additional testing revealed she had metastatic breast cancer.
Bayer, who started undergoing chemotherapy in March 2025, maintains that she showed no obvious signs of the disease—she never felt any breast lumps and her mammogram was clear.
Now, after finishing up chemotherapy treatments, she is not in remission, but on “immunotherapy indefinitely,” she tells her social media followers.
Bayer hopes her journey will help others pay better attention to their bodies needs.
She said, “I was guilty of pushing through pain and making excuses. Rest when your body needs rest.”
While sharing her symptoms in a TikTok post, concluding with a photo taken in celebration of finishing chemotherapy, Bayer urged, “Remember to slow down and listen to your body.”
@ameliasfight My Stage 4/metastatic breasties – how do you keep the faith when there’s no end in sight? Ending chemo was a huge milestone, but now I feel like I’m floundering not having a next check point or goal other than the big one of “be cancer free” (which honestly is not likely). Oddly, my mental health is in a worse place now than it was during chemo because I’ve transitioned from basic survival to trying to rebuild a life I don’t completely recognize. #cancertok #breastcancerin30s #stage4cancer #cancer #immunotherapy #chemo #chronicillness #breastcancer
In respond to her followers on TikTok asking questions about what discovered her cancer, Bayer said, “A CT caught the mass on my liver which they biopsied.
“From there, they did a mammogram, PET scan, ultrasound, and MRIs.”
She explained further in another comment, “Bloodwork showed my heart enzymes were elevated. They did a chest and abdomen CT which showed a large mass on my liver.
“They did a biopsy which came back as breast cancer. From there they did a series of scans- CT, ultrasound, pet, MRI, mammogram (this one was clear which is scary) followed by a breast biopsy and endometrial biopsy.”
Responding to a supporter who admitting to losing motivation and strives to “just keep going,” Bayer said, “I’m trying to tell myself that too.
“Trying to find the balance between positive and letting myself feel.”
Bayer also admitted to being in the “boat of humor to cope.”
@ameliasfight Take the trip. Remember to live. #carnaval #cancertok #brazil?? #uruguay #chronicillness
What is ‘HER2-positive’ breast cancer?
The human epidermal growth factor receptor 2 (HER2) is a receptor on the surface of almost all the cells in our body, and it is one of the many receptors responsible for the communication between the cells to promote their growth, division, repair, and survival.
In other words, HER2 is one of the many receptors that help cells grow and divide when the timing is right.
Living With HER2-Positive Breast Cancer
All breast cells are examined for an abundance of this protein (HER2). HER2 proteins act as receptors that regulate the growth and division of cells. If there is an excess of HER2 receptors in breast tissue (known as overexpression), it can lead to rapid multiplication of breast cells. This uncontrolled growth may result in the formation of a tumor.
Breast cancer classified as HER2-positive tends to exhibit faster growth, increased likelihood of spreading (metastasis), and a higher chance of recurrence. Despite its aggressive nature, HER2-positive cancer responds well to treatments that specifically target HER2 proteins.
HER2-Positive Metastatic Breast Cancer Treatment Options Explained
There are no distinct symptoms or specific risk factors associated with HER2-positive breast cancer, although research indicates that this type of cancer may be more prevalent among younger women.
As for metastatic breast cancer, which is also called “stage four” breast cancer and the stage of cancer Bayer was diagnosed with, this means that the cancer has spread, or metastasized, beyond the breasts to other parts of the body. It most commonly spreads to the bones, liver and lungs, but it may also spread to the brain or other organs.
When Breast Cancer Spreads to the Bones
Metastatic breast cancer is generally considered to be “incurable” at the moment, but there are a wide variety of treatment options used to battle the disease including hormone therapy, chemotherapy, targeted drugs, immunotherapy and a combination of various treatments.
Understanding treatment options for HER2-positive and metastatic breast cancer
The treatment approach for breast cancer varies greatly depending on your individual disease. Top oncologists have previously explained to us the different treatment options and why a personalized, tailored approach is so important.
Treatment for HER2-Positive breast cancer may include the following approaches (or a combination of several):
- Surgery
- Chemotherapy
- Radiation
- Targeted drugs
Treating advanced HER2-positive breast cancer
Meanwhile, treatment for metastatic breast cancer may involve:
- Hormone therapy
- Chemotherapy
- Targeted therapy
- Immunotherapy
- Surgery
- Radiation
Additionally, if the first attempts at therapy do not work, or stop working, there are other options for women with metastatic HR+ cancer.
These include:
- Alpelisib (Piqray) — A PI3K inhibitor (for PIK3CA activating mutation)
- Elacestrant (Orserdu) – An estrogen receptor blocker (for ESR1 mutated receptors)
- Olaparib (Lynparza) – A PARP inhibitor (for BRCA1/2 mutated breast cancers)
- Capivasertib (Truqap) — An AKT inhibitor
- Fam-trastuzumab deruxtecan-nxki (ENHERTU) – An antibody drug conjugate
- Sacituzumab govitecan (Trodelvy) — An antibody drug conjugate
- Pembrolizumab (Keytruda) – PD-L1 immunotherapy, for patients with high tumor mutational burden
Trodelvy was recently approved by the Food and Drug Administration (FDA) for patients with HR+, HER2- metastatic breast cancer that had stopped responding to at least two earlier courses of therapy.
Drug therapies in the setting of metastatic breast cancer are constantly changing as new drugs and drug combinations are introduced. As a result, there are a plethora of treatment options, especially for those who progress or cannot tolerate a specific treatment.
Cancer treatment is becoming more personalized thanks to next generation sequencing. Please speak to your oncologist about which options are right for you.
Immunotherapy and Breast Cancer
While there are many immunotherapy options, Keytruda is revolutionizing the cancer treatment world as it is gaining more and more U.S. Food and Drug Administration approvals to treat various types of cancers.
Currently, the FDA has granted approval for its use in treating high-risk, early-stage, triple-negative breast cancer (2021) as well as locally recurrent unresectable (not capable of being surgically removed) or metastatic triple-negative breast cancer that has the PD-L1 protein (2020). There are also various clinical trials for the use of Keytruda to treat other types of breast cancer.
Keytruda is Not for Everyone Immunotherapy Needs to Be Tailored
And this therapy has actually gained more and more U.S. Food and Drug Administration approvals to treat various types of cancers outside of breast cancer.
“Previously, (Keytruda) was used only for metastatic disease, but it’s shown such a good response there (treating early-stage triple-negative breast cancer) that now is used for earliest-stage disease, not because they have metastasis, but because it’s now been shown to reduce the risk of metastasis occurring,” Dr. Wui-Jin Koh, senior vice president and chief medical officer at the National Comprehensive Cancer Network, previously told SurvivorNet.
It’s also important to note that Keytruda is not always right for everyone, and it is just one of many immunotherapy options out there.
The first women to be cured with immunotherapy for metastatic breast cancer is Judy Perkins, who was diagnosed with early-stage ductal carcinoma in situ, or DCIS, breast cancer in 2003. (DCIS is a non-invasive breast cancer.)
Her diagnosis prompted her to get a mastectomy breast cancer surgery that removes the entire breast. But in 2013, her cancer came back, and this time, it was metastatic, or stage 4.
The standard treatment options (like chemotherapy and targeted therapies) were unsuccessful for Perkins, but she learned of an immunotherapy trial at the National Cancer Institute, which is part of the National Institutes of Health in Bethesda, Maryland, in 2015. (There are several immunotherapy clinical trials currently underway as well.)
The specific immunotherapy trial Perkins was part of, and is still part of today, is a type of adoptive cell therapy known as tumor-infiltrating lymphocyte, or TIL, therapy. During the trial, doctors removed some of her T cells, identified the ones which could recognize the cancer and then harvested those in a lab. Several months later, the cells were infused back into her body to attack the tumors. Thankfully, the treatment was a success, and Perkins has been cancer-free since 2016.
Dr. Steven Rosenberg, chief of surgery at NCI and a pioneer in the field of immunotherapy, tells SurvivorNet that Perkins was one of the first patients “to teach us that by carefully looking at (her) body’s immune cells, we could identify cells that uniquely recognize her cancer, and by growing them in a lab and giving her enough of them, we could actually cause the cancer to regress completely.”
Understanding How Immunotherapy Works
Tumor-infiltrating lymphocyte therapy is still considered an experimental treatment that’s being developed for treating solid tumors; there are various ongoing clinical trials using TIL therapy in solid tumor cancers, as well as blood cancers. Perkins says, “I’m a very weird anomaly,” as the treatment worked extremely well for her, but not so much for others in the clinical trial. But it should be noted that TIL therapy is showing great promise.
Overall, it’s important to ask your doctor about your treatment options for metastatic breast cancer. And if you’d like to search for clinical trials that are currently recruiting, you can visit clinicaltrials.gov and search “metastatic breast cancer.”
Coping With a Breast Cancer Diagnosis
If you are facing a breast cancer diagnosis, your emotions are likely to run high, which is completely normal. Psychiatrist Dr. Lori Plutchik says emotions are often fluid when coping with a diagnosis.
“The patient or person going through the stressful event should accept that emotions will be fluid. You may feel fine one day and then feel a massive wave of stress the next. It’s also important for those you look to for support, whether that’s a therapist, friends, family, or both, to understand the fluidity of stress-related emotions,” Dr. Plutchik told SurvivorNet in an earlier interview.
If a stressful event affects how you think and feel, it may be time to seek mental health treatment. This could mean traditional talk therapy, medication, changing lifestyle habits (like exercise and diet), seeking a support group, or many other approaches.
Women needing a little extra help coping with a breast cancer diagnosis should consider the following.
- Let your family and close friends know, and let them help. So many cancer survivors tell us they want and need support but are often too preoccupied to make specific requests. Urge those close to you to jump in with whatever practical help they can offer.
- Keep a journal. It can be highly cathartic to let those feelings loose on paper. Grab a pen and a lovely journal and chronicle your thoughts throughout the day.
- Join a cancer support group. Groups are available in nearly every community and offer opportunities to connect with others going through a similar journey. You’ll learn constructive insight from others who can tell you what to expect and how to stay strong on tough days.
- Consider seeing a therapist. Ask your doctor to refer you to a therapist so you can discuss your fears and concerns in a safe space. Often, vocalizing your thoughts and feelings rather than internalizing them can provide relief.
WATCH: The value of getting a second opinion.
Contributing: SurvivorNet Staff
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