You might have heard the term metastatic breast cancer but not be totally sure what it is. Simply put, metastatic breast cancer is the most advanced form of breast cancer (stage four or IV) — if cancer has metastasized, then it means that it has spread to other parts of the body.
Metastatic breast cancer occurs when breast cancer cells break away from the tumor in your breast and pass through to your bloodstream or your lymphatic system (the network of thin tubes that carry fluid around your body). Once the cells have spread, they can then settle in other organs and form new tumors.
Although this form of cancer isn’t curable, the good news is that it is very treatable. In fact, recent developments in treatment mean that people with a metastatic breast cancer diagnosis can have a better quality of life. The five-year survival rate after diagnosis for people with stage four breast cancer is 29%, according to the American Cancer Society (ACS).
Dr. Eleonora Teplinsky, head of breast medical oncology at Valley Health System, says: “We have made remarkable strides in breast cancer in the last decade. New drugs keep getting approved. We’re seeing improved survival. People are able to live their lives, work, travel, and be with their families.”
If you’ve recently received a metastatic breast cancer diagnosis, then you may well feel frightened and overwhelmed. Those feelings are completely valid and normal. Your health care provider will be able to walk you through treatment options and provide information on emotional support for you and your loved ones.
Below, Dr. Teplinsky explains everything you need to know about metastatic breast cancer, including symptoms and how it’s diagnosed.
When it comes to the signs and symptoms associated with metastatic breast cancer, there’s no one size fits all. You may have vague symptoms like nausea or unexplained weight loss. In fact, some people do not have any symptoms at first — and depending on where your cancer has spread, you might experience different symptoms.
If your cancer has spread to your bones, you may experience swelling or bone, neck, back, or joint pain. Headaches, nausea, seizures, and dizziness are all linked with brain metastasis. Confusion, vision changes, personality changes, and loss of balance may also be a sign that cancer has spread to the brain.
Shortness of breath, chest pain, difficulty breathing, or a dry cough may indicate lung metastasis. Pain or swelling in the belly, a loss of appetite, nausea, itchy skin, and jaundice (yellowing of the skin and/or eyes) are linked to liver metastasis.
It’s important to note that if you experience these symptoms, you shouldn’t automatically assume that you have metastatic breast cancer or that breast cancer has spread. You may experience them for many other reasons — including dehydration, stress, and even the common flu. It’s so important to keep paying attention to your body, and if you’re at all worried, then reach out to your health care provider. They should be able to talk you through any symptoms you’re having and run some tests and scans if needed.
Breast cancer screenings and tests can be daunting, but one of the simplest ways that your health care provider will explain your diagnosis to you is through the different breast cancer stages (0 to IV).
Stages can be split into anatomic stages and prognostic stages. Knowing your anatomic stage may give you a better understanding of the size of your tumor and the treatment options available to you.
These are the five breast cancer stages:
Stage 0: Cancer cells are found only in the ducts of the breast and have not spread to other breast tissue. This stage is also known as non-invasive cancer or ductal carcinoma in situ.
Stage I: Cancer (a tumor smaller than 2 cm) can only be found in the breast tissue or in the lymph nodes near the breast (cancer of this stage in the lymph nodes will be less than 2 mm in size). Lymph nodes are small, bean-shaped structures that are part of the body’s immune system.
Stage II: Cancer has grown in size, reaching 2 to 5 cm or more, but is still only in the breast. The lymph nodes near the breasts may contain cancer cells too.
Stage III: Cancer has spread further into the breast, or the tumor is a larger size than in earlier stages. It may have also spread to the chest wall or the skin on your breast. At this stage, cancer cells may also be found in lymph nodes in the armpit or collarbone, not just near the breast.
Stage IV: Cancer has spread to other parts of the body. This is known as metastatic breast cancer. It’s the most advanced stage of breast cancer.
Knowing your prognostic stage can give you a better understanding of the type of cancer you have and how quickly your tumor may spread. Dr. Teplinsky explains that there are three main types of breast cancer: hormone receptor-positive, triple-negative, and HER2-positive breast cancer.
Hormone receptor-positive breast cancer describes when the cancer cells have estrogen or progesterone receptors that prompt the cancer cells to grow. HER2-positive breast cancer is when the cancer tests positive for the protein human epidermal growth factor receptor 2. It’s this protein that encourages the cancer to grow. Triple-negative breast cancer describes breast cancer that doesn’t have any of these receptors.
Once you’ve explained to your health care provider that you’re concerned about new symptoms, they will likely ask you for a detailed health history which could include a physical exam.
They may then conduct an X-ray, ultrasound scan, MRI, or CAT scan and order a blood test or tumor biopsy. If you’re currently undergoing treatment, then a scan regimen may currently make up part of your health care. This can vary depending on your cancer and treatment plan.
“Patients with metastatic breast cancer will routinely have scans every few months (or sooner if necessary) to check on their status of the cancer,” Dr. Teplinksy says. “These scans may be CT scans and bone scans or PET scans. Sometimes, other scans are done as well.” These scans will help your health care provider to monitor your cancer and identify if it has spread.
If you have a metastatic breast cancer diagnosis, then the main goal of your health care provider is to improve your quality of life and help you to live longer. You can’t cure the cancer at this stage as the cancerous cells have spread to different parts of the body. However, treatment could potentially ease your symptoms.
“Metastatic breast cancer is incurable but treatable. Our goals are to treat the cancer, slow progression, and maintain/improve quality of life,” Dr. Teplinsky says. “Goals of treatment may change over time — sometimes we focus on treating the cancer, and other times, we are more focused on symptom management.”
Over the last decade, Dr. Teplinsky says that therapeutic treatment options for metastatic breast cancer have developed and increased, meaning that patients now have more options when deciding how to manage their diagnosis.
“We’re getting away from chemotherapy in some types of metastatic breast cancer, allowing people to feel as well as they can during treatment. Of course, there are side effects, but [we are] getting better at managing them,” she says. “We’ve come a long way and have a long way to go.”
Your treatment options may be based on the type of cancer you have.
Immunotherapy harnesses the power of the immune system to fight cancer cells. “Immunotherapy is used in triple-negative breast cancer (TNBC),” says Dr. Teplinsky.
In 2021, the US Food and Drug Administration (FDA) approved pembrolizumab (Keytruda) for high-risk, early-stage TNBC in combination with other treatments. It can also be used following surgery.
Targeted therapy blocks the growth and spread of cancer by targeting and blocking proteins on cancer cells. It’s often prescribed for patients who have HER2+ breast cancer. This is when the cancer cells test positive for a protein called human epidermal growth factor receptor 2.
“We have a lot of HER2 targeting agents that are really changing the landscape of treatment. We are seeing longer responses in people with brain metastases,” she says, meaning that patients are able to have a longer and better quality of life.
Hormone therapy can be effective if you have estrogen-receptor-positive cancer, progesterone-receptor-positive cancer, or both. This is when the breast cancer cells have estrogen/progesterone/both receptors that attach to either the hormone estrogen or progesterone (or both) and need these hormones for the cells to grow.
Hormonal therapy (aka endocrine therapy) is offered if your cancer is sensitive to hormones or utilizes hormones to grow. It works by preventing the body from producing as many hormones or blocking hormones connecting with receptors on cancer cells.
“We are seeing newer therapies,” says Dr. Teplinsky. These newer options work with existing hormonal therapies and newer anticancer agents that may be more effective than current treatments.
Due to the way it works, hormone therapy can bring on menopause symptoms or trigger temporary menopause. If you have any concerns about this, then you should reach out to your health care provider.
Radiation and surgery may help specific circumstances. Radiation can slow the progression of cancer or provide comfort by reducing the size of the tumor. All of these options enable people to live better and longer.
“In occasional situations, radiation can be utilized to treat metastatic breast cancer. For example, radiation can be used to provide pain relief from a bone lesion,” Dr. Teplinsky says.
“You can truly live with cancer, not just exist."
In 2020, there were approximately 168,000 women in the United States living with metastatic breast cancer, according to the Breast Cancer Research Foundation (BCRF) — and only 6% of people are diagnosed with MBC when they’re first diagnosed with cancer.
Remember that the symptoms associated with metastatic breast cancer are similar to so many other conditions. So if you notice a change in the way you feel, or if you’re at all worried, you should reach out to your health care provider.
While there isn’t a cure for metastatic breast cancer, there are so many new developments in treatment that mean that you can live a fulfilled life after diagnosis. Depending on the subtype of breast cancer that you have, there are also a number of different treatment options available.
“You can truly live with cancer, not just exist,” Dr. Teplinksy says. With newer treatments, people are able to do their day-to-day activities while undergoing treatment. Side effects from treatment, such as tiredness, still occur but are becoming more manageable.
Dr. Teplinsky says that the important thing to do is “listen to your body” and “advocate for yourself” because breast cancer can occur at any age. If you feel off, try to vocalize how you feel to someone you trust and make sure you are receiving the care you need.
If you or a loved one has been impacted by metastatic breast cancer and would like further support, there are a number of charities and organizations that work tirelessly to support cancer patients and their families. It’s important to know that you’re not alone, and there’s support available for any worries you might have.
Breast Cancer Now shares information about new treatments and support networks. Similarly, the American Cancer Society has a helpline to offer advice and support. Cancer Research UK offers a similar support service.
Written by Lauren Evoy Davis