Women who have symptoms that might be caused by a secondary breast cancer will usually have a number of tests. The type of tests usually depends on the particular symptoms. Different tests are used to examine different parts of the body. You may have had some of these tests when your primary breast cancer was discovered.

Waiting to have tests, and waiting for the results, will be a worrying time for you and the people close to you. You may worry that the cancer has come back or spread, but without the results of the tests you cannot know for sure. In this situation you may find yourself torn between believing there is some other cause for your symptoms and thinking the worst.

Often the uncertainty is the hardest part. It can sometimes be easier to cope once the results of the tests are known.

If the tests show that that you have secondary breast cancer, this can come as a huge shock. You may like to talk to your healthcare staff at the hospital, our specialist nurses or another support organisation.

A blood test will be done to check the amount of calcium in the bloodstream. Too much calcium (hypercalcaemia) may indicate that there is cancer in the bones. You may also have a blood test called a full blood count. This measures the number of different blood cells in your blood and shows how well your bone marrow is working. The bone marrow is the spongy part in the centre of most bones that produces blood cells. On their own these blood tests can’t diagnose a secondary cancer in the bone. X-rays and bone scans will usually be needed to confirm the diagnosis.

X-rays give a general picture of the condition of bones, but they may not be able to detect small areas of secondary tumours.

A bone scan is a more sensitive test which may pick up tiny areas of bone that have been affected by secondary breast cancer. A tiny amount of a mildly radioactive substance is injected into a vein, usually in the arm, and travels around the body in the bloodstream. Abnormal areas of bone absorb more radioactivity than normal bone and show up on a scanner. The scan pictures are usually taken 2–3 hours after the injection.

Bone scans can’t always tell whether an abnormal area is due to cancer or other conditions such as arthritis. For this reason, more detailed scans such as CT or MRI scans may be needed.

A chest x-ray may show whether there is any secondary breast cancer in the lungs and will also show any build-up of fluid between the membranes on the outside of the lungs (the pleura).

A CT (computerised tomography) scan may be used. This scan takes a series of x-rays which build up a three-dimensional picture of the inside of the body. The scan is painless but takes longer than an x-ray (about 10–20 minutes). Most people who have a CT scan are given a drink or injection to allow particular areas to be seen more clearly. You will probably be able to go home as soon as the scan is over.

An MRI (magnetic resonance imaging) scan is similar to a CT scan, but uses magnetic fields instead of x-rays to build up a series of cross-sectional pictures of the body. During the test you will be asked to lie very still on a couch inside a metal cylinder that is open at both ends. The whole test may take up to an hour and is painless - although the machine is very noisy. You will be given earplugs or headphones to wear.

The cylinder is a very powerful magnet, so before going into the room you should remove all metal belongings. You should also tell your doctor if you have ever worked with metal or in the metal industry or if you have any metal inside your body (for example, a cardiac monitor, pacemaker, surgical clips, or bone pins).

Some people are given an injection of dye into a vein in the arm, but this usually does not cause any discomfort. You may feel claustrophobic inside the cylinder, but you may be able to take someone with you into the room to keep you company. It may also help to mention to the staff beforehand if you do not like enclosed spaces. They can then offer extra support during your test.

Blood tests can show whether the liver is working properly, but they can’t always tell whether any problem is due to secondary cancer or another condition. Liver scans can be used to build up a clearer picture of what is happening in the liver.

Liver ultrasound scans are done in the hospital scanning department. The test uses sound waves to build up a picture of the liver and can measure the size and position of any secondary cancers in the organ. Ultrasound is painless and only takes a few minutes. CT scans of the liver take cross-sectional pictures of the abdomen.

A CT or MRI brain scan can be used to build up an accurate picture of the brain and can show areas of secondary breast cancer in the brain.

You will lie on a couch with your head inside a scanner for these tests. They are completely painless and take about half an hour.

All the tests mentioned above can help in detecting secondary breast cancer. However, they will not show up tiny groups of cancer cells. Tiny secondaries, known as micro-metastases, may lie dormant (inactive) and cause no symptoms at all. They may not be detected by the scans.

Although tests can help in detecting signs of secondary cancer, in many cases it is the woman herself who will suspect something is wrong. As mentioned before, the symptoms of secondary breast cancer are similar to those of many other far more common conditions. A woman who has back pain, for example, may suspect that breast cancer cells have spread to her spine but, in fact, the pain is more likely to be caused by a simple muscle strain. The tests listed here can help to tell whether or not symptoms are due to secondary breast cancer.

Sometimes scans may show a number of different secondaries, for example in several different areas of bone. In these situations, usually only a few of the secondaries will cause any symptoms or give any problems. Many metastases stay inactive (silent) and do not cause problems.