A fine needle aspiration biopsy (FNAB) is a medical procedure used to collect small samples of tissue from a lump or mass in the body. A thin, hollow needle is inserted into the area of concern, often guided by imaging techniques like ultrasound. This method is minimally invasive and can help doctors diagnose conditions, such as cancer, by examining the cells under a microscope. FNAB is commonly used for lumps in areas like the thyroid, breast, or lymph nodes. The procedure is quick, usually taking only a few minutes, and patients can often return to their normal activities shortly after. Results typically come back within a few days, helping guide further treatment if necessary.