The goal of the FNA procedure is to determine the cause of the lump. In the majority of the cases, this goal is achieved but in a few cases, the test is inconclusive or insufficient material is obtained for a diagnosis to be made. Whenever the specific cause of a lump is uncertain, the primary physician may recommend surgery, repeat the FNA procedure or arrange some other type of study. Despite careful performance of FNA biopsy, no medical test is 100% accurate. There is always a chance, albeit a small one that a FNA study will be inaccurate. Therefore, a lump should never be ignored after a FNA procedure. Lumps should always be monitored by patients for any changes that may occur. If changes do occur, it is highly recommended that you follow up with your primary care physician for treatment options.