Usually you begin by seeing your GP, who will ask you about your symptoms and examine you. They may arrange for you to have any tests or x-rays that are necessary. You may need to be referred to hospital for these tests and for specialist advice and treatment. If your GP suspects that you might have a sarcoma you will usually be seen at the hospital within two weeks.

At the hospital, the specialist will ask about your general health and any previous medical problems. They will also examine you, which will include feeling the area where there is pain or swelling. You may be asked to have blood tests and a chest x-ray to check your general health.

You are also likely to be asked for your permission to take a sample of the lump to examine under the microscope. This is known as a biopsy and is the only way to tell whether the lump is a cancer or a non-cancerous (benign) tumour. You may have other tests and scans to assess the lump, before a biopsy.

A biopsy can be done in either of the following ways:

A needle is put into the lump to take a sample of cells. Several samples may be taken. A local anaesthetic is injected first to numb the area. If the lump is near the surface of your body and can easily be felt, the doctor will probably just feel it to guide the needle in. If the lump is deep within the body (such as in the abdomen) or is harder to feel, the doctor will use an ultrasound scan or sometimes a CT scan to see where the needle is going and guide it into the right place.

When the cells are looked at under a microscope, the pathologist will be able to tell whether they are benign (not cancerous) or cancerous cells. If the lump is a sarcoma, further tests may be done on the sample to try to find out exactly what type of sarcoma it is.

Sometimes, particularly with children, the biopsy is done under a general anaesthetic.

For most people a needle biopsy will show whether the lump is a sarcoma. Sometimes, not enough cells are collected to give a clear answer, and then a surgical biopsy is needed.

This will only be done if a needle biopsy can’t be used, or doesn’t give a definite result. Surgical biopsy means using a surgical knife (scalpel) to open the area and remove a tissue sample from the lump. If the lump is small enough, the whole of it may be removed.

A surgical biopsy may be done under a local or general anaesthetic, depending on the position of the lump and how deep it is within the body. If the lump turns out to be benign, you may not need to have any more treatment. If it is cancer, your doctor will discuss the treatment options with you.

In the same way as with a needle biopsy, the sample will be sent to the laboratory so that it can be tested. Often a large number of studies will be done even on a very small sample. It can take from a few days to 10 days to get all the results. This can be a worrying time for you, but it is very important that an accurate diagnosis is made so that the most appropriate treatment can be given.

It may help you to talk about your worries with a partner, close friend, relative or counsellor (see the list of useful organisations).