Diagnostic problems in thyroid FNAs

The use of FNA cytology to diagnose pathologic conditions of the thyroid has increased considerably in recent years, particularly since it has reduced by half the number of patients undergoing surgery. On the one hand, this diagnostic technique has attracted a certain amount of well justified criticism, but on the other, recent cytohistologic correlations and new scientific knowledge are continually improving its application. We shall discuss the latter aspect in more detail and deal with some simple but informative points which the pathologist may find useful in daily practice.