Fine Needle Aspiration Biopsy Service

The fine needle aspiration biopsy (FNAB), division of the Cytopathology Laboratory, is a safe, minimally invasive type of biopsy that uses a very small needle to remove cells from a lump. These cells are evaluated under a microscope to determine the cause of the lump. Benign growths, cancers and infections can be diagnosed using this biopsy technique. FNAB is a very common diagnostic procedure in the United States.

The MGH Fine Needle Aspiration Biopsy Service offers expert services by trained and experienced physicians called cytopathologists. Our cytopathologists specialize in biopsying and diagnosing lumps virtually anywhere on the body. We use ultrasound imaging to biopsy masses not easily felt by physical exam. We offer local anesthesia for the procedure, but it is often not needed. 

Common sites biopsied by FNAB include the thyroid, neck, breast, lymph nodes and subcutaneous nodules.

Representative slides are looked at right away under a microscope to make sure cells are being obtained. Occasionally, the results may be known at the time of the biopsy. The cytopathologist issues a formal diagnostic report usually within 48-72 hours. If special studies are needed, a few additional days may be required. The report is sent to the doctor who requested your biopsy.

The biopsy procedure itself typically takes about 15 minutes. Biopsies that require ultrasound imaging may take longer. Please allow 45-60 minutes for your visit from start to finish. Most patients find FNAB to be a straightforward and rapid procedure, with similarities to a blood draw.


  • Amy Ly, MD - Director, Fine Needle Aspiration Biopsy Service
  • William (Bill) C. Faquin, MD, PhD

  • Joseph Misdraji, MD

  • Rosemary H. Tambouret, MD

  • Martha Bishop Pitman, MD