Surgeon-Performed Ultrasonographic Evaluation and Predication for Large Thyroid Nodules—A Case-Control Study

Abstract

BackgroundThe management of large thyroid nodules remains unclear. Ultrasonography is a central tool in the assessment of thyroid nodules, yet its role in risk stratification of large thyroid nodules has been studied only seldomly. ObjectiveThe aim of this study was to determine the utility of ultrasonography in characterizing and risk-stratifying thyroid nodules ≥3.0 cm. MethodsWe performed a retrospective, case-control study of all thyroid nodules aspirated between January 2010 and May 2014. Sonographic features of nodules ≥3.0 cm were compared with nodules <3.0 cm. All nodules were assessed by a single high-volume thyroid surgeon. Data collected included size (cm), texture, echogenicity, shape, calcifications, border, spongiform appearance, and vascularity. ResultsA total of 537 nodules were included in the study, with 137 nodules (25.5%) ≥3.0 cm comprising the study group, and 400 nodules (74.5%) as the control group. No differences were found between the 2 groups regarding age, sex, and risk factors. Nodules ≥3.0 cm were associated with an increased risk for malignancy (odds ratio 2.41 [1.08–5.38]). Microcalcifications (26.3% vs 17.5%, P = .039), hypoechogenicity (40.8% vs 23.4%, P < .001), and irregular borders (14.3% vs 3.6%, P = .001) were more prevalent in nodules <3.0 cm. Among the large nodules, hypoechogenicity (50% vs 22.8%, P = .043) and irregular margins (28.6% vs 0%, P < .001) were associated with malignancy. The specificity of irregular borders was greater in nodules ≥3.0 cm (100% vs 89.6%, P = .011). ConclusionSonographic appearances of large nodules differ from those of smaller nodules. Hypoechogenicity and irregular borders were associated with malignancy and should direct management towards a more aggressive policy of fine needle aspiration and consideration of operative resections in large thyroid nodules.