Fine-needle aspiration (FNA) is a diagnostic procedure used to investigate lumps or masses. In this technique, a thin, hollow needle is inserted into the mass for sampling of cells that, after being stained, are examined under a microscope (biopsy). The sampling and biopsy considered together are called fine-needle aspiration biopsy (FNAB) or fine-needle aspiration cytology (FNAC). Fine-needle aspiration biopsies are very safe minor surgical procedures. Often, a major surgical biopsy can be avoided by performing a needle aspiration biopsy instead, eliminating the need for hospitalization. In 1981, the first fine-needle aspiration biopsy in the United States was done at Maimonides Medical Center. Today, this procedure is widely used in the diagnosis of cancer and inflammatory conditions. Fine needle aspiration is generally considered a safe procedure. Complications are infrequent.