Computed tomography features of benign and malignant solid thyroid nodules

BACKGROUND: No previous study has investigated computed tomography (CT) features of benign and malignant solid thyroid nodules using detailed CT features and histopathological results. PURPOSE: To assess CT features of benign and malignant solid thyroid nodules in patients who underwent thyroid surgery. MATERIAL AND METHODS: From January to April 2014, 151 consecutive patients underwent neck CT before thyroid surgery. In each case, neck CT was retrospectively examined by a single radiologist. We evaluated the diagnostic accuracy of specific CT features for differentiating malignant from benign thyroid nodules using histopathological results as a reference standard. RESULTS: Of 173 thyroid nodules in 142 patients, 162 (mean diameter, 12.8 ± 10.3 mm; range, 5.0-93.7 mm) were visualized on neck CT. Of 162 nodules in 133 patients, 116 were malignant and 46 were benign as confirmed by histopathology. A multivariate logistic regression analysis showed a significant difference between malignant and benign thyroid nodules in the degree and pattern of nodular enhancement, but there were no significant differences in other CT features. In particular, thyroid nodules with exophytic configuration, irregular margin, taller-than-wide shape, punctate calcifications, or homogeneously decreased enhancement showed a high malignancy rate. CONCLUSION: The study demonstrated that the degree and pattern of nodular enhancement are helpful CT features for differentiating malignant from benign solid thyroid nodules.