Version July 2025
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What is the thyroid? —
This is a gland in the middle of the neck (figure 1). It makes thyroid hormone, which controls how the body uses and stores energy.
What is a thyroid biopsy? —
This is a procedure to check cells from the thyroid for cancer, infection, or other problem. The most common type of thyroid biopsy is done with a thin needle. This is called a "fine-needle aspiration," or "FNA," biopsy.
You might get a thyroid biopsy:
●If you have 1 or more "thyroid nodules" – These are round or oval-shaped growths in the thyroid gland (figure 2).
●If your thyroid is growing quickly and feels abnormal on an exam
●To help plan treatment for a medical problem
Most thyroid biopsies are done in a doctor's office or clinic.
How do I prepare for a thyroid biopsy? —
The doctor or nurse will tell you if you need to do anything special to prepare. You might need to temporarily stop some of your medicines. You can usually eat and drink normally before the procedure.
Before the procedure, your doctor will ask about your "health history." This involves asking about any health problems you have or had in the past, past surgeries, and any medicines you take. Tell them about:
●Any medicines you are taking – This includes any prescription or "over-the-counter" medicines, plus any herbal supplements. It helps to write down and bring a list of your medicines, or bring a bag with all your medicines with you.
●Any allergies you have
●Any bleeding problems you have – Certain medicines, including some herbs and supplements, can increase the risk of bleeding. Some health conditions also increase this risk.
Your doctor will also do an exam. They might send you to get tests, such as:
●Blood tests
●Imaging tests like an ultrasound – These create pictures of the inside of the body.
Ask the doctor or nurse if you have questions or if there is anything you do not understand.
What happens during a thyroid biopsy? —
When it is time for the procedure:
●You will lie on your back. The staff might put a pillow under your shoulders to help extend your neck.
●The doctor will clean your neck. They will probably give you an injection (shot) under your skin to numb the area.
●They might use an ultrasound to help see where to take the biopsy from. You might feel some neck pressure from the ultrasound probe or from the needle.
●The doctor will use a thin needle to remove a small sample of cells from a thyroid nodule or other area of the thyroid. They usually repeat this 1 or more times to get enough cells. The sample will be sent to a lab, and another doctor will look at the cells under a microscope. In some cases, the cells are sent for other tests. These tests can help the doctors decide if your nodule needs to be removed or can be watched.
●The doctor will hold pressure on the area and cover it with a bandage.
●Most thyroid biopsies take less than 30 minutes.
What happens after a thyroid biopsy? —
You can probably go home right away. You will likely get the results of your biopsy in about a week. Your doctor will talk to you about what the results mean and what will happen next.
If the results are not clear, your doctor will schedule another biopsy or procedure to get more information.
What are the risks of a thyroid biopsy? —
Your doctor will talk to you about all the possible risks, and answer your questions. Possible risks include:
●Bruising
●Mild pain or discomfort where the biopsy was taken
●Bleeding
Other complications are rare, and can include:
●Infection
●Injury to nearby nerves or organs
●Swelling
Sometimes, a biopsy doesn't show any results. If so, you will probably get another biopsy.
Patient education: Thyroid biopsy – Discharge instructions (The Basics)
Patient education: Thyroid nodules (The Basics)
Patient education: Nodular goiter (The Basics)
Patient education: Thyroid cancer (The Basics)
