Sometimes cancer cells spread to the bones in different parts of the body through the blood and lymphatic system.
The cells that have spread to the bone are breast cancer cells. It’s not the same as having cancer that starts in the bone.
The bone is the most common site of secondary breast cancer. The bones most commonly affected are the spine, ribs, skull, pelvis, or upper bones of the arms and legs.
When breast cancer spreads to the bone, it can be treated (often for many years) but it cannot be cured. The purpose of treatment is to try and relieve symptoms and/or slow the growth of the cancer.
What happens in the bones?
Bone contains two main types of living cells, osteoclasts and osteoblasts. Osteoclasts destroy and remove small amounts of old or damaged bone and osteoblasts help build up new bone. This process continues during your lifetime to keep the skeleton healthy and strong.
When breast cancer cells spread to the bone produce, chemicals are produced that disrupt this process. The osteoclasts become overactive resulting in more bone being broken down than is being replaced. This can lead to some of the symptoms of secondary breast cancer in the bone.
What symptoms might I have and how can they be managed?
You may have a number of different symptoms or none at all. Many people with secondary breast cancer in the bone feel quite well and their symptoms can be controlled.
You should talk to your specialist team about any new symptoms you have, as they can also be a sign of conditions, such as arthritis.
Secondary breast cancer in the bone can cause pain in or near the affected area that ranges from mild to severe. Each person’s experience of pain is different. For example, the pain may feel like a dull ache or a burning or stabbing pain. You may find that the pain is persistent, or it may be worse at certain times, such as night time. If the pain is not well controlled, it can affect your mobility and quality of life.
Most pain can be relieved or controlled. Try to be as specific as possible when you are telling your doctor or nurse where the pain is and what it feels like. You may find it helpful to record this in a ‘pain diary’ that you can get from your doctor or nurse.
Bone weakening and/or fracture
Secondary breast cancer in the bone may mean that the affected bones are weakened, which can increase the risk of fracture (breaking a bone). This is called a pathological fracture which means that the break in the bone is due to disease and not as a result of an accident.
If a bone has fractured then you may need to have surgery to try to repair the fracture. You may also be given drug treatment to stop this from happening in the future.
Spinal cord compression
If you have secondary breast cancer in the vertebrae (the bones in your spine) and a vertebrae fractures or collapses it can cause pressure on the spinal cord (spinal cord compression).
The symptoms of spinal cord compression can be:
- an increase in pain around the spine
- tenderness over the spine in the area affected
- change in sensation such as pins and needles
- weakness in the legs
- incontinence (loss of ability to control the bladder and/or bowels).
Spinal cord compression requires immediate medical attention and should be treated as an emergency. If you experience any of these symptoms it is important to contact your specialist team or GP without delay.
Hypercalcaemia (excessive calcium in the blood)
Bone releases calcium and other proteins that make the bone structure strong. Secondary breast cancer in the bone can alter the bone structure so that too much calcium is released into the bloodstream. If the calcium level gets too high you may get symptoms such as:
- being very thirsty
To relieve your symptoms you might be told to drink plenty of water but you’ll usually need to be given fluids intravenously (directly into a vein), to help flush the calcium out of the body. You may also be given other drug treatment to stop this happening in the future.
In some cases the secondary breast cancer may affect how the bone marrow works. Bone marrow is the hollow part of the bone where blood cells are made. This may cause anaemia (a lack of red blood cells). You may get symptoms such as tiredness and/or breathlessness. A blood test and a bone marrow biopsy may be needed to confirm a diagnosis. Anaemia can be treated with a blood transfusion.
Cancer-related fatigue is one of the most common symptoms experienced by people with secondary cancer. Everyone knows what it feels like to be tired sometimes, but cancer-related fatigue can feel much more severe. It can come and go or be unrelenting, and this can be distressing and frustrating. It has many causes, from psychological factors such as the stress of coping with the diagnosis, to physical ones such as the side effects of treatment or progression of the cancer.
Fatigue may have a significant impact on your ability to cope with your cancer and its treatment. For more information see our information on fatigue with secondary breast cancer.