Fine-needle aspiration in the diagnosis of head and neck lesions: a review and discussion of problems in differential diagnosis.

Fine-needle aspiration (FNA) has become the predominant initial diagnostic technique for lesions at a number of sites within the head and neck. The technique has achieved this level of usage because it is relatively inexpensive, rapid to perform, well accepted by patients, associated with low morbidity, and has a relatively high diagnostic accuracy. Sites in the head and neck amenable to FNA include the thyroid, cervical masses and nodules, salivary glands, intraoral lesions and lesions in the paraspinal area and base of skull. Diagnostic accuracy is dependent on the site of aspiration as well as the skill of the individual performing and interpreting the FNA. Studies have shown that FNA is most accurate when the individual interpreting the FNA is the same individual who obtained the aspirate material. Each site undergoing FNA within the head and neck is associated with a set of differential diagnoses and diagnostic challenges which will be discussed.