Ultrasound criteria for risk stratification of thyroid nodules in the previously iodine deficient area of Austria - a single centre, retrospective analysis

Abstract

BackgroundWe aimed to study the validity of six published ultrasound criteria for risk stratification of thyroid nodules in the former severely iodine deficient population of Austria.MethodsRetrospective, single centre, observer blinded study design. All patients with a history of thyroidectomy due to nodules seen in the centre between 2004 and 2014 with preoperative in-house sonography and documented postoperative histology were analyzed (n = 195). A board of five experienced thyroidologists evaluated the images of 45 papillary carcinomas, 8 follicular carcinomas, and 142 benign nodules regarding the following criteria: mild hypoechogenicity, marked hypoechogenicity, microlobulated or irregular margins, microcalcifications, taller than wide shape, missing thin halo.ResultsAll criteria but mild hypoechogenicity were significantly more frequent in thyroid cancer than in benign nodules. The number of positive criteria was significantly higher in cancer (2.79 ± 1.35) than in benign nodules (1.73 ± 1.18; p < 0.001). Thus, with a cut-off of two or more positive criteria, a sensitivity of 85% and a specificity of 45% were reached to predict malignancy in this sample of thyroid nodules. As expected, the findings were even more pronounced in papillary cancer only (2.98 ± 1.32 vs. 1.73 ± 1.18, p < 0.001). The six ultrasound criteria could not identify follicular cancer.ConclusionOur findings support the recently published EU-TIRADS score. Apart from mild hypoechogenicity, the analyzed ultrasound criteria can be applied for risk stratification of thyroid nodules in the previously severely iodine deficient population of Austria.

Evaluation of the Diagnostic Performance of EU-TIRADS in Discriminating Benign from Malignant Thyroid Nodules: A Prospective Study in One Referral Center

“…Nodule echogenicity is an essential feature assessed by EU-TIRADS and mild hypoechogenicity is sufficient to define an intermediate malignancy risk, even in cases of mixed composition. In our study, mild hypoechogenicity prevalence was similar in benign and malignant lesions, which is in agreement with the results of Tugendsam et al [26] and Ha et al [27], but in contrast to those reported in the prospective study by Russ et al [10]. Moreover, interobserver agreement on nodule echogenicity, reported in the literature, has been quite low [28, 29].…”

Different sonographic features of peripheral thyroid nodule calcification and risk of malignancy: a prospective observational study

“…It has been reported that malignancy is observed in 4% of solid hyperechoic nodules, but this rate rises to 26% for hypoechoic nodules [ 22 ]. Despite some conflicting consequences, the majority of papers alluded to an inverse association between echogenicity degree and thyroid cancer risk [ 23 , 24 ]. A recent meta-analysis also reported that the estimated sensitivity for hypoechogenicity in unselected nodules was 62.7% [ 17 ].…”

Value of differential diagnosis of contrast‑enhanced ultrasound in benign and malignant thyroid nodules with microcalcification

“…Gravel-like microcalcification has attracted close attention in clinical practice. Studies have indicated that microcalcification possesses a fairly high incidence rate in papillary thyroid carcinoma, becoming a major morphological characteristic of the disease, while papillary thyroid carcinoma is a primary form of malignant lesion of the thyroid nodules (5,6). In examinations, if the instruments are not sensitive enough, the pathologically puny foreign bodies of collagen and fibrosis, as well as a small amount of colloid, produce strong echoes in ultrasound, which may be confused with the echoes of true microcalcification, thus generating false-positive results.…”