Update in thyroid fine needle aspiration.

Thyroid fine needle aspiration (FNA) is a safe, cost effective, and relatively accurate method for guiding the initial management of a thyroid nodule. The popularity of thyroid FNA is reflected in the fact that over 350,000 thyroid FNAs are performed each year in the USA. As we move into the next decade, several issues pertaining to thyroid FNA are being addressed including: how to better apply thyroid FNA as a differential test for follicular-patterned thyroid tumors, how to manage the atypical thyroid FNA, and how to use thyroid FNA in the evaluation of poorly differentiated thyroid carcinomas.