Diagnosis of benign thyroid lesions: fine-needle aspiration and histopathologic correlation.

Fine-needle aspiration is now accepted as the initial procedure for diagnosing a thyroid nodule. General pathologists inevitably will be asked to interpret aspirates as this diagnostic tool continues to be more widely used. This procedure is relatively inexpensive, is safe, and nearly always provides information useful in deciding how to manage the patient. We emphasize the importance of obtaining a representative sample of good quality. This often occurs when the "interventional pathologist" performs the aspirations, but there is no reason that another practitioner cannot become expert. Both histologic and cytologic features are reviewed from normal thyroid tissue, autoimmune thyroiditis, adenomatoid nodules, and follicular neoplasms. We encourage the use of clear, simple, and uniform terminology to facilitate communication.