Fine Needle Aspiration Biopsy of Thyroid Nodules/Instructions for Patients Undergoing Core Needle Biopsy
Fine Needle Aspiration Biopsy of Thyroid Nodules
Douglas S. Ross, MD
Co-director, Thyroid Associates, Massachussetts General Hospital, Boston
The procedure described by Dr. Randall Gaz (below) is for a “core needle” or “cutting needle” biopsy. This procedure is frequently done in an Outpatient Surgical area to provide for maximum safety.
An alternative method, used in the majority of thyroid biopsies, is a fine needle aspiration technique, which is even simpler than the procedure described by Dr. Gas. The needle utilized for this procedure is quite small, even smaller than the standard needles used to sample blood. The procedure is done in a physician’s office and no advanced preparation is needed. Many patients will have a needle aspirate at the time of their initial visit. Bruising may be minimized if aspirin- and ibuprofen-containing medications are avoided prior to the procedure. However, use of these medications is not a contraindication for a fine needle aspiration. Unless you wear a turtleneck, it is not even necessary to change to a hospital gown.
The actual procedure is similar to that of a core needle biopsy. After cleaning the skin over the nodule, a local anesthetic is used to numb the skin. A tiny needle is then inserted into the nodule for 10 to 60 seconds to obtain thyroid tissue for microscopic examination. This “biopsy” may be repeated 3 to 6 times. The entire procedure usually takes less than 20 minutes. It is advisable to apply pressure to the area for about 30 minutes after the biopsy to minimize bruising and swelling. A bandaid placed over the nodule may be removed after a few hours. Most patients can return to work 30 minutes after the procedure. Vigorous physical activity should be avoided for 24 hours.
Both types of thyroid biopsies are relatively non-traumatic and well-tolerated. When appropriate, the fine needle aspiration procedure is less involved, and most patients will initially have a fine needle aspirate. There are two reasons why your physician might recommend one procedure over the other. First and most important is the availability of expertise both in performing and interpreting the biopsy.
For example, if your community does not have someone trained to do fine needle aspirations, or does not have expert cytopathologists who are able to interpret the samples made from the fine needle aspirates, then your physician may recommend that you have a core needle biopsy done by a surgeon. Second, certain types of aspirates from thyroid nodules are difficult to interpret even with expert cytopathologists. If your physician suspects that your nodule will be one of the difficult ones to diagnose, he or she may recommend a core needle biopsy to increase the chance that a definite answer would be obtained with one procedure.
Even in the best hands, approximately 10% of fine needle aspirates are non-diagnostic. This means that too little material was obtained, or the material obtained does not allow the cytopathologist to make a diagnosis. In that instance, your physician might suggest a repeat aspirate, or alternatively recommend a core needle biopsy.
(Adapted from The Bridge, Vol.8, No.1)
Instructions for Patients Undergoing Core Needle Biopsy
Randall D. Gaz, MD
Assistant Professor of Surgery, Harvard Medical School
Massachusetts General Hospital
Has your physician recommended that you have a thyroid needle biopsy? If so, the following sample of the instructions that one physician provides for patients will give you a picture of what is involved.
- Your physician has advised you to have a thyroid needle biopsy to evaluate further your thyroid condition. This will help your doctor determine whether further treatment is necessary. The procedure is simple and safe and is performed under local anaesthesia in the Outpatient Department of your hospital. Most patients experience little or no discomfort with the procedure in which a small sample of your thyroid tissue is withdrawn through a small needle for microscopic examination. (This is known as a biopsy.) The pathology report on the tissue will be available after about one week. The report will be sent to your physician.
- You should avoid taking medicines which tend to prolong the clotting time of your blood since they might increase your risk of bleeding or bruising during the biopsy. These medicines include Coumadin, Persantine, aspirin, Ecotrin, Bufferin, Anacin, ibuprofen, Advil, and Motrin. Tylenol does not have this effect on your blood and may be taken instead for headache or other mild discomfort. If you have any questions about other medication, please discuss them with your physician.
- On the day of the biopsy you may eat a light breakfast. Please have someone accompany you to and from the hospital. Bring any medications you take regularly, insurance and hospital cards, and the names and addresses of any physicians who should receive reports of the biopsy findings. Please do not wear a necklace since it would interfere with the procedure.
- Please plan to arrive at the hospital office about ten minutes prior to the scheduled time of your appointment. The nurse will greet you and direct you to a room where you may remove your shirt or blouse and put on a hospital gown in preparation for the biopsy.
- The actual procedure will require ten to thirty minutes. The doctor will first cleanse your neck with alcohol to prevent infection. Then he/she will numb the skin of your neck with a local anaesthetic. Then a needle will be inserted into the nodule several times to obtain a small sample of thyroid tissue for microscopic examination. Following this, you will be asked to stay for an additional thirty minutes for observation. You may have mild neck tenderness, discomfort in swallowing, and slight swelling or faint discoloration or bruising at the site of the biopsy. If necessary, you may take two tablets of regular Tylenol every four hours for this discomfort.
- Occasionally a patient may have a small amount of bleeding from the needle puncture site. If this happens, you should lie down and apply gentle direct pressure to the bleeding site for about ten minutes. When the bleeding has stopped, apply another clean Band-aid. If the bleeding persists, or should you develop a fever, trouble in breathing, excessive neck swelling, or unusual pain or discomfort, please telephone your surgeon’s office or your personal physician.
- You should refrain from vigorous physical activity, sports, and stress for about 24 hours following your biopsy. In general, it is safe to return to work the day after the procedure. You may shower and get your neck wet the day after the biopsy unless instructed otherwise. Please keep a Band-aid on your neck for two days. Subsequently, you may remove the Band-aid and leave the biopsy site open to the air.
Copyright © 1993 Thyroid Foundation of Canada/La Fondation canadienne de la Thyroïde.
Adapted from The Bridge, Vol.7, No.4, and Vol. 8, No. 11.
Reprinted from thyrobulletin, Vol. 14, No. 4, 1993.