To discuss the clinical value of sonographic patterns of thyroid nodules in 2015 American Thyroid Association (ATA) management guidelines for adult patients with thyroid nodules and differentiated thyroid cancer.

From January 2008 to December 2010, 483 thyroid nodules in 480 patients who underwent ultrasound-guided fine-needle aspiration biopsy (US-FNAB) in Peking Union Medical College Hospital were included in this study. Ultrasound images of the thyroid nodules were reviewed and their sonographic patterns were determined as high suspicion, intermediate suspicion, low suspicion and very low suspicion according to 2015 ATA guidelines. 112 nodules had surgical pathology. Diagnosis of other nodules depended on both US-FNAB pathology and follow-up of patients. Independent-sample t test was used to compare ages and sizes between benign and malignant nodules. Independent sample rank sum test was used to compare the malignancy risks between nodules of male and female patients, and between nodules that were solid, hypoechoic, with irregular margins, with microcalcifications and with taller than wide shape and each control group. Independent sample rank sum test was also used to compare malignancy risks of nodules with different sonographic patterns in 2015 ATA guidelines. Defining high-suspicion as positive, and intermediate to very low suspicion as negative, the diagnostic performance of sonographic patterns in 2015 ATA guidelines was calculated, including sensitivity, specificity, positive predictive value, negative predictive value, and accuracy.

Of the 483 thyroid nodules, 381 (78.9%) were benign and 102 (21.1%) were malignant proven by operation and follow-up. The malignancy rates were higher in nodules that were solid, hypoechoic, with irregular margins, with microcalcifications and with taller than wide shape than each control group, all of which had statistically significant differences (z=-6.255, -6.893, -13.000, -11.080, -6.718, P<0.001). Actual malignancy rates of nodules determined as high, intermediate, low and very low suspicion according to the ATA guidelines were 53.3% (90/169), 5.5% (6/109), 3.9% (6/154), and 0 (0/51), respectively, with statistically significant differences between the four patterns (χ²=161.462, P<0.001). When defining high suspicion as positive, and intermediate to very low suspicion as negative, the negative predictive value of sonographic patterns in ATA guidelines was relatively high (96.2%).

Sonographic patterns in 2015 ATA guidelines provide effective malignancy risk stratification for thyroid nodules. ^{High suspicion} is a good indication of US-FNAB for ^{thyroid nodules and has relatively high negative predictive value.}