Your doctor may arrange for you to have one or more of the following tests to find out the size of the sarcoma, exactly where it is and whether or not it has spread to other parts of the body.

This will be done to check your general health and to look for any sign that the cancer has spread to your lungs, as this is one of the commonest places for soft tissue sarcomas to spread to.

A CT (computerised tomography) scan takes a series of x-rays which builds up a three-dimensional picture of the inside of the body. The scan is painless but takes from 10 to 30 minutes. CT scans use a small amount of radiation, which will be very unlikely to harm you and will not harm anyone you come into contact with. You will be asked not to eat or drink for at least four hours before the scan.

You may be given a drink or injection of a dye which allows particular areas to be seen more clearly. For a few minutes, this may make you feel hot all over. If you are allergic to iodine or have asthma you could have a more serious reaction to the injection, so it is important to let your doctor know beforehand. You will probably be able to go home shortly after the scan is over.

An MRI (magnetic resonance imaging) scan is similar to a CT scan, but uses magnetism instead of X-rays to build up cross-sectional pictures of your body.

During the test you will be asked to lie very still on a couch inside a long tube for about 30 minutes. This is painless but can be slightly uncomfortable, and some people feel a bit claustrophobic during the scan. It is also noisy, but you will be given earplugs or headphones. You can usually take someone with you into the room to keep you company. It is not possible for you to have an MRI scan if you have any metal in your body such as a pacemaker, or surgical clips.

Some people are given an injection of dye into a vein in the arm, but this usually does not cause any discomfort. You will probably be able to go home when the scan is over.

This may be used if you have an abdominal lump. An ultrasound scan uses sound waves to look at internal organs such as the liver and the inside of the abdomen. You will usually be asked not to eat or to drink for a few hours before the test.

Once you are lying comfortably on your back, a gel is spread onto your abdomen. A small device like a microphone, which produces sound waves, is passed over the area. The sound waves are then converted into a picture by a computer. The test only takes a few minutes.

If the lump is in your womb, the ultrasound scan may be done by inserting an ultrasound device into your vagina. This is known as a transvaginal ultrasound scan and gives a very clear picture of the womb.

PET (positron emission tomography) scans are a newer type of scan and you may have to travel to a specialist centre to have one. They are not always necessary but you can discuss with your doctor whether one would be useful in your case. PET scans can be used to find if a sarcoma has spread to other parts of the body, or to examine any lumps that remain after treatment, to see if these are scar tissue or if cancer cells are still present.

A PET scan uses low-dose radioactive glucose (a type of sugar) to measure the activity of cells in different parts of the body. A very small amount of a mildly radioactive substance is injected into a vein, usually in your arm. A scan is then taken a couple of hours later. Areas of cancer are usually more active than surrounding tissue and show up on the scan.

It will probably take several days for the results of your tests to be ready and this waiting period will obviously be an anxious time for you. It may help if you can talk things over with a relative or close friend. You may wish to ring Cancerbackup or another support organisation for emotional support.