A Fine Needle Aspiration (FNA) Biopsy is a simple procedure that involves passing a thin needle through the skin to sample fluid or tissue from a cyst or solid mass, as can be seen in the picture below. The sample of cellular material taken during an FNA is then sent to a pathology laboratory for analysis. Fine needle aspiration biopsies are often performed when a suspicious lump is found, for example a breast lump or enlarged lymph node, or if an abnormality is detected on an imaging test such as x-ray, ultrasound or mammography. Fine needle aspiration is a relatively non-invasive, less painful and quicker method when compared to other methods of tissue sampling such as surgical biopsy. A cyst aspiration can also be achieved with a FNA, where the fluid is drained from a cyst with no need for analysis.

Performing a Fine Needle Aspiration Biopsy (FNA)

A fine needle aspiration biopsy is a simple and quick procedure. It is performed to collect a sample of cells or fluid from a cyst or solid mass, to allow the cells to be examined under a microscope. Local anaesthetic is not usually required for a fine needle aspiration, as the procedure should not be painful. Fine needle aspirations may be performed on palpable lumps (lumps which can be felt), or impalpable lumps which have been detected on ultrasound or x-ray. Once the skin has been cleaned at the needle entry point, the lump is then examined. If the lump can be felt, your doctor or surgeon will palpate the lump to position it for the needle. If the lump cannot be felt, imaging may be required to find the exact location. This can be done with ultrasound, where the surgeon will watch the needle on the ultrasound monitor and guide it to the area, or with a stereotactic mammogram (for the breast) which uses two mammograms at different angles and a computer to create exact coordinates. Fine Needle AspirationThe type of needle used for fine needle aspiration biopsy has a hollow interior and is much finer than a regular needle used to draw blood. You can see an example of what the needle may look like in the image to the right. The insertion of the needle is said to be similar to the sensation of a blood test. A vacuum or negative pressure is created in the needle and with an in and out motion of the needle, the sample is taken. Several needle insertions may be required to ensure that the sample is adequate. Once the test is completed, a small bandage will be placed over the site and you can continue your normal activities. There are generally no complications with this procedure, though you may experience some tenderness or bruising over the needle insertion site. If you experience any bleeding, swelling, fever or pain that is not relieved with paracetamol, contact your doctor immediately. It is not recommended that you use aspirin to relive pain as it may worsen any bruising.