Needle aspiration biopsy ( NAB ) , also known as fine needle aspiration cytology ( FNAC ) , fine needle aspiration biopsy ( FNAB ) and fine needle aspiration ( FNA ) , is a medical procedure performed to diagnose certain kinds of medical conditions , such as lumps in the neck . A thin needle is inserted into a mass or lump to extract cells that will be examined under a microscope . A recent study showed that in one case a needle biopsy of a liver tumor resulted in spread of the cancer along the path of the needle , and concluded that needle aspiration was dangerous and unnecessary .