Fine-needle aspiration biopsy of thyroid nodules: comparison of diagnostic performance of experienced and inexperienced physicians.

OBJECTIVE: To determine whether a difference exists in terms of obtaining adequate cytologic samples from ultrasound-guided fine-needle aspiration cytology (US-FNAC) between experienced and inexperienced physicians in a tertiary referral center.

METHODS: In a prospective design, all patients with thyroid nodules of at least 10 mm in diameter were referred for US-FNAC tissue sampling as a part of their diagnostic work-up. Between May 2006 and September 2009, 997 euthyroid patients with 1,320 thyroid nodules were referred for US-FNAC by the attending endocrinologist (experienced physician) or 1 of 2 endocrinology fellows (inexperienced physicians).

RESULTS: Of the 1,320 nodules, 713 biopsy specimens were obtained by the experienced physician and 607 were obtained by the inexperienced physicians. Nodule size was significantly larger in the endocrinologist's group of patients than in the fellows' group of patients (17 mm versus 14 mm, respectively; P<.001). The inadequacy rate of the US-FNAC procedures performed by the experienced physician (22 of 713 thyroid nodules or 3.1%) was significantly lower than for those performed by the inexperienced physicians (102 of 607 thyroid nodules or 16.8%) (P<.001).

CONCLUSION: We conclude that, with increasing operator experience, the number of inadequate cytologic specimens generated by US-FNAC procedures is substantially reduced. This limits both direct and indirect costs and also minimizes the risks of possibly unnecessary surgical procedures.