According to the 2015 American Thyroid Association (ATA), referred risk stratification and thyroid nodules with intermediate- and low-suspicion patterns are difficult to diagnose. The objective of this study is to evaluate the diagnostic performance of contrast-enhanced ultrasonography (CEUS) and elastosonography (ES) for the differentiation of these thyroid nodules. From November 2011 to June 2016, a total of 163 thyroid nodules with intermediate- and low-suspicion patterns in 150 consecutive patients at our hospital were studied before surgery. With surgical pathology as the standard, the diagnostic value of CEUS and ES was analyzed. There were 29 (17.8%) malignant lesions and 134 (82.2%) benign lesions. The enhancement patterns of CEUS, the echogenicity, and the elastography were significantly different between malignant and benign lesions (P < 0.05). Heterogenous enhancement was more common in malignant nodules, and the sensitivity, specificity, positive predictive value, negative predictive value, and odds ratio were 51.7, 88.1, 48.4, 89.4, and 10.1%, respectively. The diagnostic accuracy of CEUS was better than the conventional ultrasound [area under the curve (AUC), 0.729 vs. 0.616, P = 0.021]. The enhancement patterns of CEUS were helpful in the differential diagnosis of thyroid nodules with intermediate and low suspicion.

Background: The purpose of this study was to conduct thyroid ultrasound examinations on a large sample of subjects and explore the occurrence, distribution, and characteristics of thyroid nodules and thyroid cancer to provide some information on the epidemic trend of thyroid nodules and cancer. Methods: The thyroid ultrasonic examination results of 19 895 healthy physical examinees who visited the Department of Health Management, Peking Union Medical College Hospital from January 2009 to December 2011 were analyzed retrospectively to determine the detection rate and characteristics of thyroid nodules. Fine needle aspiration or surgical resection was suggested to subjects suspected of having thyroid cancer. Results: The detection rate of thyroid nodules was 42.6% (8 480/19 895), 40.0% (4 661/11 678) in men and 46.5% (3 819/8 217) in women. The detection rate noticeably increased with increasing age. The detection rate of thyroid nodules by palpation was obviously lower than by ultrasonic examination in various age groups. Among those with thyroid nodules, 61.3% were multiple and 38.7% were solitary; multiple nodule was the major type both in men and women. Twenty-nine cases of malignant nodules were solitary, and 30 cases of malignant nodules were multiple. There was no significant difference. The detection rate of thyroid cancer was 0.30% for the entire group of examinees, and 0.15% in men and 0.50% in women. Among all sex and age groups, 30- to 40-year-old women had the highest detection rate (0.76%). The detection rate of thyroid nodules correlated with age, systolic blood pressure, height, and weight. Increasing age and/or higher systolic blood pressure correlated with a higher detection rate, while smaller height and weight also correlated with a higher detection rate with significant differences. However, there were no significant correlations between the detection rate and diastolic blood pressure or body mass index. Conclusions: The detection of thyroid cancer increased significantly, especially in women. Thus, precautions needed to be taken. Regular physical examination and timely intervention after detection of malignant nodules are critical to improve the prognosis in thyroid cancer patients.