Benign thyroid nodules with suspicious ultrasound features: sonographic-pathologic correlation

Objective To analyze the ultrasonographic characteristics of benign thyroid nodules with suspicious ultrasound features and investigate the misdiagnosis reasons from the pathology in order to improve the accuracy of ultrasound in the diagnosis of benign thyroid nodules. Methods Three hundred and seventy-nine patients with benign thyroid nodules underwent surgery and had histopathologic diagnosis at our hospital. In all, 24 patients with 31 nodules were misdiagnosed as thyroid cancer by ultrasonography, the pre-operative diagnosis of ultrasonography in 31 thyroid nodules were retrospectively reviewed in light of their pathologic results. Results ①Compare the suspicious ultrasound features of the nodules with diameter of 10 mm or less and larger than 10 mm, the majority nodules with a diameter of 10 mm or smaller showed solid, marked hypoechogenicity, taller-than-wide shape; the majority nodules with a diameter of larger than 10 mm showed solid, marked hypoechogenicity, ill-defined margin, calcification. ②The Thyroid Imaging Reporting and Data System (TI-RADS) lexicon was introduced to describe the lesions: 28 nodules were categorized as TI-RADS 4c and 3 nodules were categorized as TI-RADS 5. ③Hisologic analysis of benign thyroid nodules with suspicious ultrasound features revealed severe fibrosis, calcification. Conclusions The sonographic finding of a few benign thyroid nodules were similar to thyroid cancer. Benign thyroid nodules with suspicious ultrasound features were histologically characterized by severe fibrosis. Key words: Ultrasonography; Thyroid nodule; Pathology