What is secondary breast cancer?

Secondary breast cancer is when cancer cells from a cancer that started in the breast spread to other parts of the body. The cancer that started in the breast is called primary breast cancer.

Secondary breast cancer is also called advanced breast cancer or metastatic breast cancer. The most common places for breast cancer to spread to are the:

Rarely, breast cancer may spread to other parts of the body, such as the bone marrow, ovaries or lining of the tummy (abdomen) which is called the peritoneum.

Breast cancer can spread to different parts of the body. This does not mean it will go to all these places.

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Understanding secondary breast cancer
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31 Oct 2018
A booklet explaining secondary breast cancer, covering the causes and symptoms, diagnosis, staging and grading...

How does cancer spread from the breast

Often primary breast cancer does not come back after treatment. But sometimes the cancer cells spread through the blood or the lymphatic system to other parts of the body.

Breast cancer cells that have spread may form another tumour. The tumour in the other part of the body is made up of breast cancer cells. Your doctor will treat it with drugs that work for breast cancer. For example, a secondary breast cancer in the lung is treated with breast cancer drugs. It is not treated with drugs for lung cancer.

Local and regional recurrence of breast cancer

Breast cancer that comes back in the breast, chest, scar or lymph nodes nearby is called a local or regional recurrence. This is not secondary breast cancer. If you have a local or regional recurrence, you may have tests to check the cancer has not spread to other parts of the body. 

We have more information about breast cancer recurrence.

Symptoms of secondary breast cancer

The symptoms of secondary breast cancer depend on where in the body the cancer has spread to. If it has spread to the bones there might be a painful area in a bone. If it has spread to a lung it may cause breathlessness.

Some people have general symptoms. They may feel generally unwell for no obvious reason. Tell your doctor or nurse if you have any new symptoms. If you are worried, we have more information about the symptoms of secondary breast cancer.

Causes of secondary breast cancer

There are no specific risk factors for secondary breast cancer. The risk factors are the same as for primary breast cancer.

Diagnosis of secondary breast cancer

You may be diagnosed with secondary breast cancer after having tests to check a new symptom. This could be through your GP or at a breast cancer follow-up clinic. Sometimes there may be no obvious symptoms and the diagnosis is made after routine follow-up tests.

Some women who have just been diagnosed with primary breast cancer have tests that show the cancer has already spread to other parts of the body. Sometimes the secondary breast cancer is diagnosed first and tests show that it first started in the breast.

Your cancer doctor or nurse will ask you about your symptoms and general health. You may need some of the following tests:

  • Blood tests

    Blood tests cannot diagnose secondary breast cancer. But they may show that you need further tests. You may have blood tests to check how well the liver, kidneys or bone marrow are working or to check the level of calcium in your blood. Blood tests can also measure tumour markers for secondary breast cancer. These are proteins produced by some cancers. Your doctor can tell you whether tumour marker tests are helpful in your situation.

  • Bone x-rays

    If you have a painful area in your bones, you may have an x-ray to check for signs of cancer. The x-ray may also show weakened areas of bone that are at a higher risk of fracture. It may not show small areas of secondary cancer. You usually have a bone scan to confirm the diagnosis.

  • Bone scan

    A bone scan shows up abnormal areas of bone. A small amount of a radioactive substance is injected into a vein. You need to wait for 2 to 3 hours between having this injection and the scan.

  • Chest x-ray

    A chest x-ray can help to see if there is secondary breast cancer in the lungs. It can also show any build-up of fluid between the membranes on the outside of the lungs (the pleura). You will also usually have a lung CT scan.

  • Liver ultrasound

    A liver ultrasound uses soundwaves to build up a picture of the liver. It is painless and only takes a few minutes.

  • MRI scan

    An MRI scan uses magnetism to build up detailed pictures of your body.

  • CT scan

    A CT scan takes a series of x-rays, which build up a three-dimensional picture of the inside of the body.

  • PET-CT scan

    A PET-CT is a combination of a CT scan, which takes a series of x-rays to build up a three-dimensional picture, and a positron emission tomography (PET) scan.

  • Biopsy

    A biopsy is when a doctor removes a sample of tissue or cells from an abnormal area to be checked under a microscope. Where you have the biopsy taken from depends on your symptoms and scan results. For example, you may have a biopsy from your lungs or liver.

Waiting for test results can be a difficult time. We have more information that can help.

Stages of secondary breast cancer

The results of your tests tell your doctors if breast cancer has spread to another part of the body. This is called the stage of the cancer.

Doctors often stage breast cancer by dividing it into four number stages. Secondary breast cancer is always stage 4. This is when the cancer has spread to other parts of the body, such as the bones, lungs, liver or brain. We have more information about staging breast cancer in our primary breast cancer information.

Receptors for secondary breast cancer

Breast cancer cells may have receptors (proteins). Hormones, or a protein called HER2, can attach to the receptors and encourage the cells to grow. A doctor called a pathologist tests cancer cells taken during a biopsy or surgery for these receptors. Your doctor uses the results of these tests to help plan your treatment.

If you have had primary breast cancer before, the receptors may not be the same as when you were first diagnosed. This may mean different treatments are useful. Your doctor may be able to diagnose a secondary cancer from your scan results. But they may still recommend a biopsy to find out more about the cancer cell receptors.

Cancer that does not have receptors for either hormones or HER2 is called triple negative breast cancer.

Oestrogen receptors

Breast cancer that has receptors for the hormone oestrogen is called oestrogen receptor-positive (ER-positive) breast cancer. Hormonal therapies are often used to treat ER positive breast cancer.

HER2

Some breast cancers have too much of a protein (receptor) called HER2 (human epidermal growth factor receptor 2) on the surface of their cells. This is called HER2 positive breast cancer. Specific targeted therapy drugs are used to treat HER2 positive breast cancer.

Treatment for secondary breast cancer

A team of specialists will meet to discuss the best possible treatment for you. This is called a multidisciplinary team (MDT).

Your doctor and nurse will talk to you about the best treatment for you. They will also ask you about your preferences. They will talk to you about things to consider when making treatment decisions. You may have some treatments as part of a clinical trial.

Secondary breast cancer can be controlled, often for many years, but it cannot be cured. Because of new and improved treatments, women with secondary breast cancer are living for longer. The aim of treatment is to control the cancer, improve the symptoms and help you to live well for longer.

The treatment you have will depend on:

  • where the cancer is in your body
  • if it is ER positive or HER2 positive
  • previous breast cancer treatment you have had.

You may have a combination of treatments.

Treatments for secondary breast cancer include:

  • Hormonal therapy

    Hormonal therapies are drugs that lower your oestrogen level or block its effects on the cancer. They only work if you have oestrogen receptor (ER) positive cancer. Some people have hormone therapy with a targeted therapy drug.

  • Chemotherapy

    Chemotherapy uses anti-cancer (cytotoxic) drugs to destroy cancer cells. You may have chemotherapy on its own or with a targeted therapy drug. A treatment called electrochemotherapy may be used to treat secondary cancer in the skin.

  • Targeted therapy

    Targeted therapy drugs interfere with signals that tell the cancer cells to grow. Depending on the receptors on the cancer cells, you may have a targeted therapy as part of your treatment.

  • Radiotherapy

    Radiotherapy uses high-energy rays to destroy cancer cells. It is used to relieve pain and other symptoms when breast cancer has spread to the bones, skin or brain. We have more information about controlling symptoms of secondary breast cancer.

  • Surgery

    Surgery is not usually used to treat secondary breast cancer. It is sometimes used to strengthen a bone that has been weakened by cancer. We have more about this in our information about controlling symptoms of secondary breast cancer. Surgery is also sometimes used to treat cancer that has spread to the spine, liver or brain.

  • Bone strengthening drugs

    If you have cancer that has spread to the bones, you may be given bone-strengthening drugs called bisphosphonates or a targeted therapy called denosumab. These strengthen the bones, relieve bone pain and reduce the risk of a broken bone (fracture). We have more about this in our information about controlling symptoms of secondary breast cancer.

  • Steroids

    Steroids can be given along with chemotherapy drugs to prevent an allergic reaction. They are also used to control symptoms. They help reduce swelling if the cancer has spread to the liver or to the brain.

Controlling symptoms of secondary breast cancer

The symptoms of secondary breast cancer are usually helped with cancer treatment. Sometimes this works quickly and you may notice an improvement within a few days. But sometimes it may take a few weeks before you feel better.

There are also lots of other ways to control and manage symptoms. We have more information about controlling symptoms of secondary breast cancer.

Living with secondary breast cancer

You will see your cancer doctor or specialist nurse regularly during and after treatment. This means that any symptoms or problems can be managed early on. You may have regular scans to check how the cancer has responded to treatment.

You may need treatment at different times or have ongoing treatment with hormone therapy. There may be long periods when the cancer is controlled and you are getting on with day-to-day life.

We have more about well-being and coping in our information about living with secondary breast cancer.

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