A fine-needle aspiration (FNA) biopsy is often used to take cell 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) will be used instead.
For core biopsies, after local anaesthetic has been given, a hollow needle is inserted through the skin and into the area being examined. X-ray, ultrasound, CT or MRI scanning will often be used to help guide the needle to exactly the right place.
When the needle is in position, it will cut out a small sample of tissue. For core biopsies, local anaesthetic is usually used to numb the area, so that you won't experience any pain or discomfort.
In many 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 obtain a larger tissue sample. In some cases, when a cyst (a benign fluid-filled swelling) is suspected, a fine needle will be used to drain the fluid and the cells sent for examination (cytology).
A thicker, hollow needle is used for taking organ biopsies, such as of the liver or kidneys. These are often carried out with imaging guidance (ultrasound or CT). You may be asked to hold your breath for a few seconds while the needle is inserted into your abdomen (tummy).
A thick needle is 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
- white blood cells
- platelets (blood-clotting cells)
A large number of different health conditions may be responsible for these types of blood abnormalities. Where a diagnosis has already been made, samples of marrow may be taken to check how well treatment is working – for example, in leukaemia.
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 pelvic bone, just below your waist. You'll usually have a local anaesthetic to numb the area. You may also be given a sedative to help you relax and cope with any discomfort or anxiety.