Frequently asked questions
1. The fine needle aspirate.

What is a fine needle aspirate?

A fine needle aspirate (FNA) is a type of biopsy in which a small, thin (fine) needle is used to collect cells from a lump or mass. The FNA is used to diagnose superficial lesions located just under the skin, or masses in deep organs. It differs from other biopsies in that cells, rather than solid tissue are used to make the diagnosis.

What are the advantages to doing a fine needle aspirate instead of a surgical biopsy?

The FNA is safer and typically less painful for the patient than other procedures which involve an incision or take a core of tissue with a larger, cutting needle. A diagnosis can often be made more rapidly with an FNA, generally within 24 hours depending on what special tests must be performed on the aspirated cells. Fine needle aspiration is less expensive than surgical biopsy. FNA does not cause scarring which may interfere with subsequent surgery or radiologic studies. FNA is an excellent technique for diagnosing many tumors and infectious processes. For some diseases, including inflammatory conditions requiring a knowledge of tissue architecture, a surgical biopsy is preferred.

Who will perform the fine needle aspirate?

FNAs can be performed successfully by any physician with adequate training and experience, including pathologists, primary care physicians and surgeons. Lesions located in internal organs like the kidney are usually aspirated by a specially trained radiologist. The pathologist (the physician who makes the diagnosis) is often in the best position to do superficial FNAs, since he/she has the opportunity to talk to and examine the patient, and to order special tests on the aspirated cells as needed. The patient's medical history and information from the physical exam are often vital to the correct diagnosis. This information should be communicated to the pathologist by whichever physician performs the FNA.

Do I need to fast or do anything special before showing up for the FNA?

No fasting or special preparation is needed.

What happens during the FNA?

For superficial FNAs, after discussing the procedure and doing a brief physical exam we place the patient in a comfortable position (seated or lying down). The skin is sterilized with alcohol or Betadine pads. The needle is attached to a syringe and placed into the mass. Gentle suction is applied and the needle moved in several short motions to draw cells into the needle and hub of the syringe. Then the physician withdraws the needle and makes cytologic preparations including smears on glass slides similar to Pap smears. It's usually necessary to repeat the FNA several times to ensure that enough cells are collected to make the diagnosis. The total amount of time that the needle is inserted into the lesion averages about 10 seconds per aspirate (approximately 30 seconds in all). The patient may be in the office for 20-30 minutes or more, depending on whether the pathologist is available to review slides to determine if adequate material is being obtained.

Does the FNA hurt?

Yes, but much less than most other medical procedures. Because the needle is so slender (for example, it's thinner than the needles used to draw blood for blood tests) most patients report that pain is minimal. A local anesthetic such as Lidocaine can be injected beforehand, a procedure which in itself causes mild pain and which may obscure small lesions, making it more difficult for the physician to obtain diagnostic material. If the lesion is already painful or is in a sensitive location, don't hesitate to discuss local anesthesia with your physician.

Is the FNA safe?

Fine needle aspirates have an excellent safety record and cause fewer complications than other biopsy techniques. Patients who have superficial FNAs may experience temporary bruising at the site of the FNA and rarely develop a local soft tissue infection which can be treated with antibiotics. Bleeding is usually minimal and easily controlled by the application of external pressure on the FNA site. You should tell your physician if you are taking blood thinning medication, which can increase the tendency to bleed. Potential complications are discussed beforehand with the patient and listed on a consent form that the patient is asked to sign before the procedure begins.

How do I find out the results?

Material obtained by fine needle aspirate is processed in a cytology laboratory and interpreted by a pathologist skilled in cytopathology. A report is communicated to the referring physician, who will then discuss the results and any further diagnostic tests or treatment options with you.



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