Malignancy risk of thyroid nodules with nonshadowing echogenic foci

Abstract

This study was conducted to determine the malignancy risk and diagnostic value of various types of nonshadowing echogenic foci (NEF) in the risk stratification of thyroid nodules. Methods: A total of 1,018 consecutive thyroid nodules (≥1 cm) with final diagnoses were included. The presence of NEF was determined and types of NEF were classified according to the presence of a comet tail artifact (CTA), location, and size through a prospective evaluation. The associations with malignancy, malignancy risk, and diagnostic value of various types of NEF were assessed. Results: Intrasolid punctate NEF without CTA was the only type of NEF that was an independent predictor of malignancy (P<0.001). The malignancy risk of intrasolid punctate NEF without CTA was substantially higher in solid hypoechoic nodules than in isoechoic or nonsolid nodules (71.3% vs. 9.2%, P<0.001). In solid hypoechoic nodules, slightly increased sensitivity (70.8% vs. 67.9%) for malignancy and a similar malignancy risk (71.4% vs. 71.3%) were observed for intrasolid punctate NEF (with or without CTA) and intrasolid punctate NEF without CTA, respectively. NEF with CTA at the margin of the cystic component was not associated with malignancy or benignity in nonsolid nodules (P≥0.236). Conclusion: Intrasolid punctate NEF without CTA was the only independent predictor of malignancy. However, solid hypoechoic nodules with intrasolid punctate NEF should be classified as high-suspicion nodules regardless of coexisting CTA. Other types of NEF had no added value for detecting malignancy compared to intrasolid punctate NEF without CTA.

Impact of the ultrasonography assessment method on the malignancy risk and diagnostic performance of five risk stratification systems in thyroid nodules

“…Some solid nodules determined by the retrospective assessment might have included nodules with minimal cystic changes, which may have resulted in a relatively lower malignancy risk because nodules with minimal cystic changes have a lower malignancy risk compared to purely solid nodules without minimal cystic changes [20]. The lower malignancy risk of microcalci cation in the prospective dataset may be explained by the higher proportion of partially cystic or iso-and hyperechoic nodules among all nodules with microcalci cations in the prospective dataset because the malignancy risk of partially cystic or iso-and hyperechoic nodules with microcalci cations is signi cantly lower than that of solid hypoechoic nodules [8,21]. Our subgroup analysis showed that the lower malignancy risk of microcalci cations in the prospective dataset was found only in partially cystic or iso-and hyperechoic nodules compared to the retrospective dataset, but it was not found in solid hypoechoic nodules.…”

2021 Korean Thyroid Imaging Reporting and Data System and Imaging-Based Management of Thyroid Nodules: Korean Society of Thyroid Radiology Consensus Statement and Recommendations

“…4 ) [ 35 69 70 71 72 ]. Although echogenic foci with comet-tail artifacts at the margin of the cystic component are commonly found in benign nodules [ 69 73 ], they are not specific for benign nodules ( Fig. 3 ) [ 73 ].…”

“…Although echogenic foci with comet-tail artifacts at the margin of the cystic component are commonly found in benign nodules [ 69 73 ], they are not specific for benign nodules ( Fig. 3 ) [ 73 ]. Notably, echogenic foci with comet-tail artifacts within the solid component or at the margin of the cystic component should not be considered as US features of benign nodules [ 72 73 74 75 ].…”

“…3 ) [ 73 ]. Notably, echogenic foci with comet-tail artifacts within the solid component or at the margin of the cystic component should not be considered as US features of benign nodules [ 72 73 74 75 ]. Intracystic echogenic foci with comet-tail artifacts are strongly correlated with the colloid content of benign nodules [ 70 ].…”

Impact of the ultrasonography assessment method on the malignancy risk and diagnostic performance of five risk stratification systems in thyroid nodules

“…Some solid nodules determined by the retrospective assessment might have included nodules with minimal cystic changes, which may have resulted in a relatively lower malignancy risk because nodules with minimal cystic changes have a lower malignancy risk compared to purely solid nodules without minimal cystic changes [20]. The lower malignancy risk of microcalci cation in the prospective dataset may be explained by the higher proportion of partially cystic or iso-and hyperechoic nodules among all nodules with microcalci cations in the prospective dataset because the malignancy risk of partially cystic or iso-and hyperechoic nodules with microcalci cations is signi cantly lower than that of solid hypoechoic nodules [8,21]. Our subgroup analysis showed that the lower malignancy risk of microcalci cations in the prospective dataset was found only in partially cystic or iso-and hyperechoic nodules compared to the retrospective dataset, but it was not found in solid hypoechoic nodules.…”