You will probably begin by seeing your GP who will examine your breasts. If your GP is not sure what the problem is, or thinks that cancer may be present, you will be referred to a specialist for advice or treatment. If your GP suspects that you might have a cancer you should be seen at the hospital within two weeks.

At the hospital, the specialist will ask you about your general health and any previous medical problems, before examining you. They will examine your breasts and feel for any enlarged lymph nodes under your arms and at the base of your neck. You may have a blood test and a chest x-ray to check your general health.

The following tests may be used to diagnose breast cancer. You may have one, two or a combination of the tests. It can help to have a friend or relative with you when you go for any tests or to get your results.

A mammogram is a low-dose x-ray of the breast tissue. You will need to take off the clothes from the top part of your body, including your bra. The radiographer will then position you so that the breast is against the x-ray machine and gently but firmly compressed with a flat, clear, plastic plate. Two mammograms (from different angles) are taken of each breast.

The breast tissue needs to be squashed to keep the breast still and to get a clear picture. Most women find this uncomfortable and for some women it is painful for a short time. You will need to stay still for a few seconds while the picture is taken.

Mammograms are usually only used for women over the age of 35. In younger women the breast tissue is more dense, which makes it difficult to detect any changes on the mammogram.

An ultrasound uses sound waves to build up a picture of the breast tissue. Ultrasound can tell whether a lump is solid (made of cells) or is a fluid-filled cyst. It can also often tell whether a solid lump is likely to be benign or malignant.

You will be asked to take off your clothes from the upper part of your body and lie down on a couch. An ultrasound specialist will then put gel onto your breast and gently rub a small microphone-like device over the affected area. This shows a picture of the internal tissue of the breast on a screen. Ultrasound is painless and only takes a few minutes.

A colour Doppler ultrasound machine can show the blood supply to the lump. The blood supply shows up as patches of red or blue colour on the scan and the pattern of the blood flow can help tell the difference between a cancer and a benign lump.

A needle (core) biopsy may be done. A doctor uses a needle to take a small piece of tissue from the lump or abnormal area. Needle biopsies are often done using ultrasound to guide the doctor to the lump. Local anaesthetic is injected into the area first to numb it. During the biopsy you may feel a little soreness or a sensation of pressure, but this should last only for a short time. Several biopsies are usually taken at the same time.

The samples are then sent to a laboratory to be looked at by a doctor who is an expert at diagnosing illness by looking at tissue under a microscope (a pathologist). Depending on the number of biopsies taken, the breast tissue may be quite bruised and sore afterwards. This may take a few weeks to completely disappear.

A fine needle aspiration (FNA) is a quick, simple procedure which is done in the outpatient clinic. Using a fine needle and syringe, the doctor takes a sample of cells from the breast lump and sends it to the laboratory to see if any cancer cells are present. The breast is sensitive, so the needle aspiration may be quite uncomfortable. The breast may be bruised and sore for a week or so afterwards. A local anaesthetic may be used to numb the area, particularly if an FNA is being taken from a lymph node in the armpit or in the neck.

Sometimes (especially if the lump is small) a needle aspiration may be carried out in the x-ray department. The doctor uses x-ray or ultrasound guidance to make sure that the needle takes cells from the abnormal area of the breast or lymph node.

Samples of your blood will be taken to check your general health, the number of cells in your blood (blood count) and to see how well your kidneys and liver are working. Your blood may also be tested to see whether it contains particular chemicals (tumour markers), which are sometimes produced by breast cancer cells.

Sometimes an excision biopsy may be done. The whole lump is removed under a general or local anaesthetic and sent to a laboratory for examination under a microscope. This may mean an overnight stay in hospital, but it is done as day surgery in some hospitals.

If a lump is too small to be felt, but has shown up on a mammogram or ultrasound, the radiologist may need to mark the area for the surgeon before the excision biopsy. This is done by inserting a very small wire (a guide wire) under local anaesthetic, using x-ray or ultrasound guidance. The procedure is known as wire localisation.

Many hospitals have a special 'one stop' breast cancer clinic. This means you will have all the necessary tests and get some of the test results on the same day. In other hospitals it can take longer for the results to come through. Guidelines recommend that all tests should be performed and all results of these tests should be available within three weeks of you being seen in the clinic.

This waiting period can be an anxious time for you and it may help to talk about your worries with a partner, close friend, relative, breast care nurse, counsellor or support organisation. You could also speak with one of the nurses on our helpline.