Diagnostic value of contrast enhanced ultrasound combined with ultrasound-guided fine-needle aspiration in differentiating malignant and benign thyroid nodules

Abstract

Objective To evaluate the diagnostic value of contrast enhanced ultrasound (CEUS) combined with ultrasound-guided fine-needle aspiration (US-FNA) in differentiating malignant and benign thyroid nodules. Methods A retrospective review of preoperative CEUS and US-FNA data of 161 thyroid nodules confirmed by surgical pathology from 145 patients was performed. The CEUS enhancement patterns of whole phase hypo-enhancement, uneven hypo-enhancement and early phase hypo-enhancement were taken as the diagnostic criteria for malignant thyroid nodules. According to the Bethesda System, the grade≥Ⅳ was taken as the cytologic criteria for diagnosis of malignant thyroid masses. The 161 thyroid nodules were divided into large nodules group(the longest diameter of thyroid nodules were higher than 1.0 cm) and small nodules group (the longest diameter of nodules were higher than 0.5 cm but lower than 1.0 cm). The diagnostic value of CEUS, US-FNA and the combination were evaluated respectively in the the two groups. Results In large nodules group, the sensitivities of CEUS, US-FNA and the combination were 88.0%, 81.3%, 94.7%, respectively; their specificities were 88.5%, 100%, 88.5%, respectively. There was no statistically difference in sensitivity between CEUS and US-FNA (P=0.301), the sensitivity of the combination was higher than US-FNA (P=0.004). In small nodules group, the sensitivities of CEUS, US-FNA and the combination were 52.4%, 78.6%, 92.9%, respectively; their specificities were 94.4%, 100%, 94.4%, respectively. There was statistically difference in sensitivity between CEUS and US-FNA (P<0.05), the combination had the highest sensitivity (P<0.05). Conclusions For thyroid nodules whose longest diameter higher than 1 cm, there is no statistically difference in sensitivity between CEUS and US-FNA. The combination had higher sensitivity than US-FNA. For thyroid nodules whose longest diameter higher than 0.5 cm but lower than 1.0 cm, US-FNA provided higher sensitivity than CEUS, the combination provided higher sensitivity than single CEUS or US-FNA. Key words: Contrast-enhanced ultrasound; Thyroid nodules; Biopsy, needle