While metastatic breast cancer can’t be cured, treatment can shrink cancer, prevent additional spread, and improve quality of life.

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An estimated 313,510 new diagnoses of breast cancer will be made in 2024.

Most breast cancers are diagnosed while they’re only in the breast or when they’ve spread regionally. Only about 6% are diagnosed when they’ve spread distantly, although breast cancer can also recur at distant sites.

Breast cancer that has spread away from the breast and into distant organs and tissues is called metastatic breast cancer. There are several potential treatment options for this type of breast cancer.

Many breast cancers are treated with the goal of eliminating the cancer and preventing it from coming back. However, because metastatic breast cancer has spread more widely, it’s considered incurable.

Instead, the treatment of metastatic breast cancer focuses on:

Metastatic breast cancer is typically treated using one or a combination of the following:

  • hormone therapy
  • targeted therapy
  • chemotherapy
  • immunotherapy

The type of treatment you receive can depend on the characteristics of your cancer as well as your age, overall health, and personal preference.

Local treatments, such as radiation therapy and surgery, may also be used for some people with metastatic breast cancer in specific situations.

Some breast cancers are positive for hormone receptors (HRs) like estrogen, progesterone, or both. Binding of these hormones to HRs on breast cancer cells can boost the growth of the cancer.

People with HR-positive metastatic breast cancer may be treated with hormone therapy, which blocks the activity of estrogen or lowers its production. Hormone therapy may be combined with another treatment type, such as targeted therapy.

Examples of hormone therapy drugs used for metastatic breast cancer include aromatase inhibitors or tamoxifen. The specific type of drug used can depend on your menopausal status.

The side effects and risks of hormone therapy can include things like:

Targeted therapy specifically targets markers in or on breast cancer cells. It’s often used in combination with other treatments like hormone therapy and chemotherapy.

Breast cancers that overexpress the HER2 receptor (HER2-positive) can be treated with targeted therapy directed at HER2. This may include the following drugs:

There are also targeted therapy drugs available for metastatic breast cancer that are HER2-negative but is positive for HRs. These include:

  • the AKT inhibitor capivasertib (Truqap)
  • CDK4/6 inhibitors like abemaciclib (Verzenio), palbociclib (Ibrance), and ribociclib (Kisqali)
  • the mTOR inhibitor everolimus (Afinitor)
  • the PI3K inhibitor alpelisib (Piqray)

Additional targeted therapy drugs include:

The side effects of targeted therapy can depend on the drug that’s used. However, some common potential side effects to be aware of are:

Chemotherapy disrupts the process of growth and division in cancer cells, resulting in their death. It’s typically used for cancers that are HR-negative or for HR-positive cancers that haven’t responded to hormone therapy.

Chemotherapy may be combined with targeted therapy. Some examples of chemotherapy drugs used, either alone or in combination, for metastatic breast cancer are:

Chemotherapy drugs have broad activity. That means that they can also impact healthy cells that divide quickly, such as those in the bone marrow, GI tract, and hair follicles. Due to this, chemotherapy can have side effects like:

Immunotherapy is a type of treatment that boosts your immune system’s response to cancer. It may be combined with other treatments like targeted therapy.

An immunotherapy drug called pembrolizumab (Keytruda) can be used for some people with metastatic breast cancer, particularly those with triple-negative breast cancer.

The most common side effects of pembrolizumab include:

In contrast to systemic treatments that act throughout the body, local treatments are those directed at a certain area. Local treatments for breast cancer may include surgery and radiation therapy.

These treatments can be used to:

  • ease symptoms, such as:
    • pain from tumors that are pressing on nearby tissues
    • neurological symptoms and pain from tumors pressing on nerves, the brain, or spinal cord
  • reduce the risk the complications, such as fractures from bone metastases
  • improve quality of life

There’s no type of alternative therapy that can effectively treat metastatic breast cancer.

However, many people with cancer use these approaches to help with symptoms and boost their quality of life. When an alternative approach is used alongside conventional treatment, it’s called complementary therapy.

The National Center for Complementary and Integrative Health points out that some research supports the use of the following approaches as complementary therapies in people with cancer:

Complementary therapies can have a variety of risks and side effects associated with them. Due to this, always check in with your doctor before starting with a complementary approach.

Starting treatment for metastatic breast cancer can feel overwhelming, and a variety of questions may come to mind. Below are some examples of questions to ask your care team about your treatment:

  • What’s the first-line treatment that you’ve recommended for my cancer?
  • Why is this treatment being recommended?
  • What is the goal of my treatment?
  • Are there other treatment types that can be used for my cancer? If so, what are they, and how will they impact my outlook?
  • How long will I receive treatment?
  • Where will I have my treatment? How long will each treatment session last?
  • What are the side effects of my treatment? Are there things I can do to prevent or ease side effects?
  • When should I contact you about treatment side effects? When should I go to the emergency room?
  • Will my treatment have any lasting or long-term side effects?
  • What happens if the first-line treatment stops working?

Where to find support if you’re having treatment for metastatic breast cancer

If you’ve been diagnosed with metastatic breast cancer, the resources below can help you to find various types of support:

  • The American Cancer Society (ACS): The ACS has a wealth of information on breast cancer and also has various patient programs and services and a Cancer Survivors Network
  • BreastCancer.org: This site also has a large amount of information on breast cancer and its treatment as well as a discussion forum to connect people receiving breast cancer treatment.
  • The Susan G. Komen Foundation: The Susan G. Komen Foundation provides a financial assistance program to help those with breast cancer who need additional financial support.
  • Living Beyond Breast Cancer: Living Beyond Breast Cancer is a nonprofit with three private support groups on social media and potential funding opportunities for people with breast cancer who need further financial aid.

Your care team is also a valuable asset. They may be able to give you information about breast cancer support groups or other resources in your area.

The outlook for people with metastatic breast cancer can depend on the following factors:

  • the specific type of breast cancer you have
  • where in the body the cancer has spread to
  • the cancer’s HR and HER2 status
  • the genetic characteristics of the cancer
  • how quickly the cancer is growing and spreading
  • the type of treatment used and how the cancer responds to it
  • your age and overall health

Each person with metastatic cancer is different. Be sure to have an open conversation with your care team about what to expect. They can consider the factors above to give you a better picture of your individual outlook.

How long do you live with metastatic breast cancer?

According to the SEER Database of the National Cancer Institute (NCI), the 5-year survival rate for people with metastatic breast cancer is 31%.

Where does breast cancer typically spread?

The NCI notes that the most common areas for breast cancer to spread to are the bones, brain, liver, and lungs.

What are the red flags of metastatic breast cancer?

General symptoms of metastatic cancer are nonspecific and include things like fatigue, reduced appetite, and unintended weight loss. Additional symptoms depend on where the cancer has spread to and may include:

Can you go into remission with metastatic breast cancer?

Sometimes. What was formerly called “remission” is now referred to as “no evidence of disease” (NED), and while rare, it is possible for some types of metastatic breast cancer to cause an individual to go into a state of NED.

A 2022 study reports that approximately 1–6% of individuals with HER-positive metastatic experienced resolution of tumors on imaging tests following HER2-targeting therapies.

Metastatic breast cancer is considered incurable. However, it can be treated with the goals of shrinking the cancer, preventing further spread, and boosting quality of life and survival.

Typically, systemic treatments like hormone therapy, targeted therapy, and chemotherapy are used for metastatic breast cancer. Local and complementary therapies can also be used to ease symptoms and improve quality of life.