OR32-04 The Usefulness Of The Contrast-enhanced Ultrasound (CEUS) In Evaluating The Risk Of Malignancy In Thyroid Nodules

Disclosure: A. Zylka: None. K. Dobruch-Sobczak: None. M. Jedrzejczyk: None. H. Piotrzkowska-Wroblewska: None. P. Goralski: None. J. Galczynski: None. E. Bakula-Zalewska: None. M. Dedecjus: None. Objectives Ultrasonography (US) is a primary method used in the evaluation of the thyroid nodules, but there is no single feature predicting malignancy preoperatively with high accuracy. Contrast-enhanced ultrasound (CEUS) provides information about the vascular perfusion and hemodynamics in the thyroid nodules. Therefore, the aim of this paper was to evaluate the usefulness of CEUS in the differential diagnosis of thyroid nodules. Methods Between the years 2021 and 2022, 182 adult patients (149 women and 33 men, aged 18-85) underwent CEUS of a thyroid nodule classified after fine-needle aspiration biopsy with II-VI Bethesda category. During CEUS examination 1.5 ml of SonoVue contrast has been injected and followed by analysing of qualitative CEUS enhancement patterns. All patients subsequently underwent thyroid operation and histopathologic results were used to confirm or exclude the risk of malignancy. Analysis of the visual CEUS enhancement patterns was performed by two experienced specialists in thyroid ultrasonography. Fifteen CEUS qualitative parameters of nodules were estimated and compared with normal thyroid parenchyma including: ring enhancement; low-, iso- and high enhancement; homo- or heterogenous enhancement; slow, fast or equal wash-in and wash-out and centripetal, centrifugal or diffuse enhancement. The statistical analysis of the obtained results was performed using the logistic regression. First sensitivity, specificity and AUC were calculated only for CEUS qualitative features. Then the model was extended using the results based on US B-mode imaging which involved three suspicious features: irregular margins, microcalcifications and marked hypoechogenicity. Results Histopathologic results included 61 benign thyroid nodules (in 51 women and 10 men) and 121 thyroid carcinomas (in 99 women and 22 men). The analysis has pointed five CEUS parameters statistically significant in differential diagnosis between benign and malignant thyroid nodules: low, homogenous and centrifugal enhancement, ring enhancement and slow-wash-out of the contrast. The model, using the above parameters evaluated the risk of malignancy of thyroid nodules with sensitivity of 85.12% and specificity of 45.90% with 0.75 AUC. Including the B-mode features, the sensitivity, specificity and AUC were 85.95%, 62.30% and 0.86, respectively. Conclusions Preliminary results indicate that CEUS is an useful tool in the evaluation of the risk of malignancy in thyroid nodules. The combination of the qualitative enhancement parameters and US B-mode sonographic features increases the usefulness of the method in differential diagnosis between benign and malignant nodules. However, further multicenter studies should be performed in order to standardize qualitative and quantitative CEUS features. Presentation: Sunday, June 18, 2023