Thyroid Cytopathology

The evaluation of thyroid nodules by fine needle aspiration (FNA) is one of the most challenging tasks in all of cytopathology. A cytologist must understand the clinical presentation of thyroid diseases, their defining histopathologic and cytopathologic features, and even the intricacies of patient management. Drs. Clark and Faquin have provided a valuable framework for cytologists learning (and continuing to learn) this exacting discipline. Org- ized around a practical algorithm, the authors lay out a rational and concise approach toward acquiring the necessary skills for the cytologic diagnosis of thyroid nodules. The first edition, published in 2005, was a very welcome addition to the cytology literature. This new edition, with updated terminology for reporting thyroid FNA results, builds on the success of their approach. Why are we examining such challenging specimens? Clearly, the clinical need is there. Over 50% of adults have one or more thyroid nodules. Surgical excision of all nodules is certainly neither practical nor desirable. Enter FNA, a minimally invasive cellular sampling method that has proven to be a highly useful screening test for thyroid cancer. Because of it, thousands of patients with a benign diagnosis are spared unnecessary surgery every year, and those with cancer are reliably triaged for appropriate therapy.