A fine needle aspiration biopsy is a test done to see if a tumor is benign (non-cancerous) or malignant (cancerous.)
Fine needle aspiration (FNA) is done by inserting a thin needle into a tumor and removing cells that can be evaluated under the microscope. A pathologist looks at the cells to see if the suspicious tumor is cancer, and if it is cancer, what type of cancer.
With lung cancer, the needle is inserted into the chest through the skin. Doctors can make sure the needle goes to the right part of the lung by watching it through ultrasound or a CT scanner. If a lesion is more easily approached than those in the lung (for example, lymph nodes that can be felt), FNA may be used on that site instead of the lungs.
FNA is less invasive than an open biopsy, which is a biopsy that requires an incision in the skin to remove tissue. The most common problems with the test are bleeding or an air leak (pneumothorax) that may require further treatment.