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Fine Needle Aspiration Biopsy

Fine needle aspiration, also known as FNA, can help determine the nature of palpable masses or nodules. The results can guide further evaluation of a mass by additional testing or surgical removal.

Any superficial or deep palpable lesion from breast, thyroid, lymph nodes, salivary glands or soft tissue can be evaluated by fine needle aspiration biopsy. The procedure is quick, inexpensive and reliable and allows a diagnosis generally within 24 to 48 hours and even within minutes in some cases.

Performing the Fine Needle Aspiration Biopsy

The pathologist performing the procedure will take a brief history, examine the nodule and explain the procedure. A consent form is signed by the patient. Local anesthetic is usually not used for this procedure. There is minimal discomfort and the needle will leave a mark no bigger than a needle stick from a blood test. The pathologist or clinician will sample the palpable mass with a thin needle.

Two to three aspirations are usually obtained to provide accurate diagnosis. Each sample takes only about 10 to 15 seconds to obtain. The adequacy of the sample is judged by microscopic examination. The entire procedure from start to finish takes no more than 20 to 30 minutes and is done in the doctor's office.

Fine Needle Aspiration Results Reporting

Results are faxed to the referring physician in one to two working days. If additional studies need to be performed, an additional two to three days may be required. Most results are grouped into four categories:

  1. Benign, not cancerous
  2. Malignant, cancerous
  3. Non-definitive, which most often indicates the need for a surgical biopsy
  4. Infectious

In the case of a clearly malignant diagnosis, fine needle aspiration biopsy quickly establishes the need for further evaluation of the lesion.

In a small proportion of cases, fine needle aspiration biopsy may fail to find a malignancy when it is present. The lesion will need to be followed by your referring physician and further tests may need to be performed.

Possible Complications

The most common complication from fine needle biopsy is slight bruising or tenderness at the needle entry site. Applying direct pressure after the procedure can minimize this risk. Discomfort can be relieved by an over-the-counter pain reliever or the application of an ice-pack for a short period. Infection is extremely rare.

Service Availability

The SLUCare Cytopathology service provides reliable, accurate and prompt cytopathology diagnostic services. The laboratory meets or exceeds the highest standards of the College of American Pathologists and CLIA 88.

Cytopathologists are available Monday through Friday during regular working hours. To schedule a fine needle aspiration biopsy, please contact the pathology department at 314-977-4555.

Professional Staff  

Eric Staros, MD
Huazhang Guo, MD, PhD
Daniel Miller, MD, PhD

Cytology Supervisor
Eric Politte, CT (ASCP)