Lumps and masses

This page is reference information compiled from the cited sources. It is not medical advice. For any decision about health, diagnosis or care, consult a qualified professional.

What it is

Fine-needle aspiration (FNA) is a diagnostic procedure used to investigate lumps or masses. This technique involves inserting a thin, hollow needle into the mass to sample cells that are then stained and examined under a microscope, which is called a biopsy. The sampling and biopsy together are termed fine-needle aspiration biopsy (FNAB) or fine-needle aspiration cytology (FNAC). It is a minimally invasive procedure that can often avoid the need for a more invasive surgical biopsy. The modern procedure is widely used to diagnose cancer and inflammatory conditions. Fine needle aspiration is also the main method used for chorionic villus sampling and for many types of body fluid sampling.

Key facts

Fine-needle aspiration biopsy is a very safe, minimally invasive procedure. Complications are infrequent, with complications beyond bruising and soreness being rare. However, problematic cells can be too few, leading to an inconclusive result, or missed entirely, resulting in a false negative. The first fine-needle aspiration biopsy in the United States was performed at Maimonides Medical Center in 1981. This type of sampling is performed either when the nature of a lump or tissue mass is uncertain or, for known tumors, to assess treatment effect or obtain tissue for special studies. When the lump can be felt, the procedure is usually short and simple and performed by a cytopathologist or surgeon; otherwise, it may be performed by an interventional radiologist under guidance, requiring more preparation and time. It is also used for ultrasound-guided aspiration of breast abscess, breast cysts, and seromas.

When to seek professional help

Professional care is associated with situations where a biopsy is performed on a lump or tissue mass when its nature is uncertain. Professional care is also associated with performing this biopsy for known tumors to assess the effect of treatment or to obtain tissue for special studies. The source states a biopsy is advised for biopsies in the breast. Professional evaluation is indicated when the procedure is performed by a cytopathologist, a surgeon, or an interventional radiologist, particularly when guidance is needed. Professional care involves preparation including suspending certain medications, completing blood tests, and possibly administering sedation for very anxious patients. Post-procedure, professional monitoring occurs during an observation period, and complications, though uncommon, are managed by professionals, such as treating infection with antibiotics or addressing bleeding.

Source: Fine-needle aspiration (CC BY-SA 4.0 (Wikipedia)), retrieved 2026-10-04.