Abstract:Objective: Compared ACR TI-RADS, ATA and KSThR ultrasound classifications performance in predicting high risk of partially cystic nodules Methods: The sonography features from a total of 293 partially cystic thyroid nodules in our hospital were retrospectively analyzed to compare the difference between benign and malignant nodules, and also assess the predictive values of the three TIRADS in identifying high risk of partial cystic thyroid nodules. Results: 46.1% (135/293) nodules underwent surgery, including 83 papillary thyroid cancer (PTC) and 52 benign nodules. 53.9% (158/293) nodular goiter diagnosed by cytology didn’t submit to operation. The sonographic characteristics were analyzed between benign and malignant nodules, the hypoechogenicity of solid portion (OR: 6.684,95%CI:3.158-14.148,P<0.001), the presence of microcalcification (OR: 2.459,95%CI:1.839-3.287,P<0.001) and irregular margin (OR: 2.587,95%CI:1.068-6.264,P=0.035) showed a statistically significant association with malignant nodules by Binary logistic regression analysis. ACR TI-RADS exhibited the highest area under the curve of ROC (0.843, 95% CI: 0.791-0.895,p<0.001), and that of the ATA and KSThR were 0.797 (95% CI: 0.733-0.862,p<0.001) and 0.785 (95% CI: 0.717-0.8524,p<0.001), respectively. Conclusion: The presence of the hypoechogenicity of solid portion, microcalcification and irregular margin showed high risk of malignancy in partially cystic thyroid nodules. The ACR TIRADS classification system showed slightly more effective in the risk stratification of partially cystic nodules than ATA and KSThR , and was suggested to apply in clinical practice to manage the partially cystic thyroid nodules.