Like any cancer, breast cancer can spread to other parts of the body. Breast cancer that has invaded bone can have a significant effect on quality of life, but there are treatments to help manage symptoms and slow disease progression.

Read on to learn more about metastatic breast cancer in bones, including symptoms and what you can expect from treatment.

“Metastasis” describes the spread of cancer from where it started to another part of the body. This happens when cancer cells break from the primary tumor and enter the lymph system or bloodstream. From there, they can travel throughout the body and form new tumors.

Metastatic breast cancer in bones is not the same as bone cancer. It’s made up of breast cells, not bone cells. It’s also called stage 4 or advanced breast cancer.

According to a 2020 study, bone is the most common site of breast cancer metastasis.

Breastcancer.org says that for more than half of women with metastatic breast cancer, bones are the first site of metastasis. The bones most likely to be affected are the:

  • ribs
  • spine
  • pelvis
  • long bones in your arms and legs

Other common sites of breast cancer metastasis include your liver and lungs.

Signs and symptoms vary depending on where the cancer has spread and how big the tumors are. They may include:

Pain

Bone pain from breast cancer metastasis tends to be constant. It may get worse when you’re active and typically doesn’t let up when you rest. This can make it difficult to sleep well.

Bone fracture

Cancer weakens bone, making it fragile and susceptible to fracture. Sudden, severe bone pain can be due to a fracture, even after a minor injury.

Compressed spinal cord

Cancer in your spine puts pressure on nerves. This can lead to back or neck pain. It can also cause numbness or weakness in your legs as well as bladder and bowel concerns.

Learn more about the symptoms of late stage metastatic breast cancer.

Hypercalcemia

Cancer can cause bones to break down and release calcium into the bloodstream. Hypercalcemia is a condition in which you have a high level of calcium in your blood. Symptoms can include:

  • frequent urination
  • thirst
  • dehydration
  • nausea
  • loss of appetite
  • constipation
  • fatigue
  • headache
  • confusion

Your doctor will likely start with a discussion of your symptoms and a physical examination.

Diagnostic testing may include blood tests to find out whether your blood has too much calcium or alkaline phosphatase (ALP), either of which can be elevated because of bone metastasis.

But this can also be due to other conditions. Blood tests alone can’t confirm metastatic breast cancer in bones or pinpoint the location.

Sometimes, an X-ray can reveal bone metastasis. Other times, your doctor may order one or more of the following imaging tests to look for signs that cancer has reached bone:

  • Bone scan: A bone scan is a type of nuclear medicine test. Before the scan, a small amount of a radioactive substance is injected into a vein. This causes cancer to show up as dark areas or “hot spots” on the scans.
  • CT scan: A CT scan combines X-ray and computer technology to provide cross-sectional images. It can highlight the inside of a specific bone or area of bone.
  • MRI scan: MRI uses radio waves and a magnetic field instead of X-rays to create detailed images of specific bones.
  • PET scan: A PET scan is a nuclear imaging test. Radioactive tracers allow cancer cells to appear as bright spots on the scans.
  • Bone biopsy: In some cases, your doctor may want to do a bone biopsy to confirm the diagnosis and get more information about the cancer. Metastatic cancer in your bones may have different characteristics from the primary breast cancer. This information can help determine which treatments are most likely to be effective.

Breast cancer isn’t a single disease. It’s a group of diseases. So, treatment is personalized to reflect your:

  • specific type of breast cancer
  • extent of metastasis
  • previous treatments
  • age and overall health

Pain relief

Depending on your level of pain, medications may include acetaminophen or nonsteroidal anti-inflammatory drugs (NSAIDs). Your doctor may also prescribe opioids to manage severe pain.

Localized treatment

Local treatment depends on which bones are affected and how weak they’ve become. Treatment may include:

  • Radiation therapy: This therapy destroys cancer cells in your affected bone.
  • Surgery on the bones: This treatment may help stabilize a fractured bone.
  • Bone-strengthening drugs: These medications include bisphosphonates and denosumab to strengthen bones and reduce related skeletal injuries, such as fractures, spinal cord compression, or other complications from bone metastases.

Systemic treatment

Your options for systemic treatment vary according to the characteristics of the cancer. This includes hormone and human epidermal growth factor receptor 2 (HER2) status as well as other specific tumor markers or genetic mutations.

Your doctor will consider any previous cancer treatments and adjust if necessary.

Systemic treatments may include:

  • chemotherapy, such as:
    • topoisomerase inhibitors
    • mitotic inhibitors
    • anti-metabolites
    • anti-tumor antibiotics
    • corticosteroids
  • hormone therapy, such as tamoxifen, aromatase inhibitors, or fulvestrant
  • anti-HER2 drugs, such as trastuzumab, pertuzumab, and many others
  • targeted therapy, such as CDK4/6 inhibitors, PARP inhibitors, and many others
  • immunotherapy (biologic therapy), such as atezolizumab or pembrolizumab in combination with chemotherapy

Clinical trials are studies that research the effectiveness of new therapies. By participating in a trial, you may have access to innovative treatments that aren’t available anywhere else.

If you’re interested, ask your doctor for information about clinical trials that might be a good match. You can also search ClinicalTrials.gov.

Treatment for bone metastasis can effectively manage metastatic breast cancer for some time.

Many people with bone metastasis continue to have a good quality of life and live for many years.

That said, treatment for metastatic cancer doesn’t usually eliminate all cancer cells. Eventually, these cells become resistant to therapy.

According to the American Cancer Society, the 5-year relative survival rate for metastatic breast cancer is 31% for women and 20% for men.

It’s important to note that cancer survival statistics are based on people who received diagnoses and treatments at least 5 years ago. That means the statistics don’t reflect the effectiveness of the newest treatments — and treatments are improving every year.

It’s also worth noting that survival rates for metastatic cancer are very diverse and depend on the individual and the type of cancer they have.

For example, people with hormone receptor-positive cancers and HER2-positive breast cancers may do well for a long time, compared with those who have triple-negative breast cancers. So, lumping all forms of metastatic cancer into one statistic can be misleading.

Regardless of the type of breast cancer you have, early diagnosis and treatment are crucial, as survival rates are higher in the early stages of breast cancer. And remember, the right treatment for stage 4 breast cancer can improve quality of life and longevity.

Mental health support

Learning you have metastatic breast cancer can be a lot to deal with. You may cycle through a wide range of emotions.

Lean on family and friends and consider reaching out for mental health support. If you’d like to share your feelings with others who are going through the same thing, these organizations can help you find an appropriate virtual or in-person support group:

Was this helpful?

Below are some commonly asked questions about metastatic breast cancer in bones.

How long can you live with metastatic breast cancer in bones?

Some studies suggest people with breast cancer that has metastasized to the bones live 19–25 months on average.

However, the American Cancer Society states the 5-year relative survival rate for metastatic breast cancer is 31% for women and 20% for men.

All in all, your outlook depends on several factors, including the extent of metastasis, the type of breast cancer, previous treatments, and your age and overall health.

What happens when breast cancer spreads to the bones?

When breast cancer spreads to the bones, you may experience pain, bone fracture, a compressed spinal cord, and high levels of calcium in your blood.

What are the final stages of metastatic breast cancer?

End stage metastatic breast cancer may eventually stop responding to treatment. This means your care team will start focusing on keeping you comfortable and treating your symptoms.

These symptoms may include:

  • fatigue
  • shortness of breath
  • new, unexplained pain
  • changes in appetite or digestion difficulties
  • weight loss
  • headaches
  • emotional changes, including shifts in mood

Metastasis breast cancer most commonly spreads to the bones. Some signs include constant bone pain, fractures, compressed spinal cord, and hypercalcemia.

A doctor usually diagnoses metastasis breast cancer in bones using a variety of imaging tests and sometimes a bone biopsy.

Treatment options are personalized based on factors like your cancer type, extent of metastasis, and previous treatments.

While treatments can effectively manage the cancer and improve your quality of life, complete elimination of cancer cells is rare. Survival rates vary depending on your individual factors and cancer type.

Early diagnosis and tailored treatment are crucial for better outcomes, as newer treatments continue to improve survival rates over time.