Fine needle aspiration biopsy of a thyroid nodule: a comparison of diagnostic performance of experienced and inexperienced physicians
Alptekin Gursoy1, Cuneyd Anil1 & Betul Erismis2
Objectives: Ultrasound-guided fine needle aspiration biopsy (US-FNAC) technique has the advantage of obtaining tissue for cytological examination. The diagnostic yield may depend on factors related to both technical aspects and the lesions sampled. However, the variability between experienced and inexperienced physicians in obtaining adequate cytological sample has not been specifically studied previously. The aim of the study was to determine whether there is a difference in terms of adequacy of cytological material between experienced and inexperienced physicians in a tertiary referral center-based service.
Methods: 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 workup. From May 2006 to September 2009, 997 euthyroid patients with thyroid nodules were referred for US-FNAC by the attending endocrinologist (experienced) or endocrinology fellows (inexperienced) in the outpatient clinics of the Endocrinology department of Baskent University Hospital in a prospective design.
Results: Of the 1320 nodules, 713 were biopsied by the experienced physician and 607 were biopsied by the inexperienced physicians. There were no differences in age, gender, thyroid function, nodule location and distribution of nodule structure between the two groups. Nodule size was significantly higher in the endocrinologist group than the fellow group (17 vs 14 mm, respectively; P<0.001). The inadequacy rate of the FNAC performed by the experienced physician (22/713 thyroid nodules, 3.1%) was significantly lower than those performed by inexperienced physicians (102/607 thyroid nodules, 16.8%) (P<0.001).
Conclusion: We conclude that with increasing operator experience, the number of inadequate cytological specimens generated by ultrasound-guided fine needle aspiration biopsies of thyroid nodules greatly reduces. This limits both direct and indirect costs, and also the risks of possibly unnecessary surgeries.