There are many ways of getting a tissue sample, depending on the type of tissue being collected and where in the body it's being taken from.

CT scanning is often used to guide some types of biopsy.

Scraping cells

In some cases, scraping cells from the surface layer of tissue, such as inside the mouth, is enough to provide a suitable sample for examination. This type of ‘scraping biopsy’ can be slightly uncomfortable but is not painful, so anaesthetic isn't required.

A cervical screening test is a procedure during which a small brush-like instrument is used to gently remove a sample of cells from the neck of the womb (cervix). The cells are then examined under a microscope for any abnormal changes (dysplasia).

If there are abnormal cell changes, the cells may be cancerous, or there may be an increased risk that they will become cancerous.

Punch biopsy

A punch biopsy can often be used to investigate skin conditions, such as deep spots and sores.

During a punch biopsy, a special surgical instrument is used to make a small hole in your skin and remove samples of the top layers of tissue. If you have a punch biopsy, you will usually be given a local anaesthetic to numb the area.

Alternatively, a scalpel (a sharp medical knife) may be used to remove a small amount of surface skin. The wound will be closed using stitches.

Needle biopsy

A fine-needle aspiration (FNA) biopsy is often used to take tissue samples from organs or from lumps that are below the surface of the skin. If a larger sample is needed, a core needle biopsy (CNB) may be used instead.

To obtain the sample, a special, hollow needle is inserted through your skin and into the area being examined. Ultrasound or X-rays will be used to help guide the needle to exactly the right place.

When the needle is in position, it will ‘suck out’ a sample of tissue. If you have a needle biopsy, a local anaesthetic will usually be used to numb the area so that you won't experience any pain or discomfort.

Breast lumps

In most cases, a needle biopsy can be used to get more information about a breast lump. The needle is inserted into the lump and a sample of tissue will be taken for testing.

A core needle biopsy (CNB) is often used to gain a larger sample of tissue. In some cases, a fine needle aspiration (FNA) biopsy may be used to drain a cyst.

Organs

A thicker, hollow needle is used for taking organ biopsies, such as the liver or kidneys. You will be asked to breathe in and hold your breath while the needle is inserted into your abdomen.

It takes a few seconds for a small tissue sample to be taken. A local anaesthetic is usually used for this type of biopsy because you need to be awake to breathe in.

Bone marrow

A thick needle is also used to take samples of bone marrow (the soft, jelly-like tissue found in the hollow centre of large bones).

Bone marrow biopsies can be carried out for a number of different reasons, including to find out why you have:

• a low or high number of red blood cells (anaemia)
• a low or high number of white blood cells (leucopenia)
• a low or high number of platelets (blood-clotting cells)

A number of different health conditions may be responsible for these types of blood abnormalities, such as leukaemia (cancer of the bone marrow and white blood cells).

Samples of bone marrow are also sometimes taken to check how well treatment for leukaemia is working, or to determine how far certain types of cancer have progressed (what stage it's at).

Bone marrow biopsies are usually taken from the top of the pelvis bone, just below your waist. You will usually have a local anaesthetic to numb the area, and you may also be given a sedative (medication) to help you relax and cope with any discomfort, nerves or anxiety.

Endoscopic biopsy

An endoscope is a medical instrument that's used to look inside your body. It's a thin, flexible tube with a light and a camera at one end. Tiny cutting tools can also be attached to the end of an endoscope to allow the surgeon to take a tissue sample.

An endoscope can be inserted through your throat, back passage (anus), or through small cuts made by the surgeon.

Depending on the area of the body being investigated and the entry point of the endoscope, either local or general anaesthetic will be used.

Excisional biopsy

An excisional biopsy is used to remove a larger area of tissue, such as a lump, for closer examination.

Depending on where in the body the lump is located, an excisional biopsy may be carried out under either a local or a general anaesthetic.

Perioperative biopsy

A biopsy is sometimes carried out during an operation for another, unrelated reason. A tissue sample is taken during surgery and is checked immediately so that the surgeon gets the results quickly and can decide how to progress with treatment.

A lump found during surgery may be removed completely if the patient is still under anaesthetic and has previously given their consent (approval).

Testing a tissue sample

After a tissue sample has been taken, it will be sent to a laboratory so that it can be examined under a microscope and the tissue’s cells can be tested.

Closely examining the cells in the tissue sample enables scientists to determine whether they are normal or abnormal. For example, cancerous cells look and behave differently to normal cells.

As well as looking at the tissue sample, chemical or genetic tests can also be carried out. For example, a chemical test is sometimes used to help diagnose cystic fibrosis (where the lungs and digestive system become clogged with thick sticky mucus). A chemical reaction will occur if the gene for cystic fibrosis is present in the tissue cells.

Tests for cystic fibrosis and other genetic conditions can even be carried out on a cell sample taken from an unborn baby. The sample is taken from the placenta using a pre-natal biopsy known as chorionic villus sampling (CVS).