Relationship Between Contrast-enhanced Ultrasound Features And Tumor Size In Papillary Thyroid Carcinoma

ObjectiveTo analyze the characteristics of contrast-enhanced ultrasound(CEUS)and quantitative parameters of time-intensity curve(TIC)in different sizes of papillary thyroid carcinoma(PTC),and to investigate the relationship between CEUS features and tumor size.Materials and methodsRetrospectively analyzing 112 patients with 129 papillary thyroid carcinomas who underwent contrast-enhanced ultrasonography and then received FNA or surgical treatment in our hospital from October 2017 to January 2018.According to nodule size,they were divided into two groups:group A?1cm and group B>1cm.CEUS was performed in two groups,and the features of enhancement were observed including enhanced intensity(low,equal or high),enhanced mode(mixed,centripetal)and homogeneity of contrast medium(uniform and uneven distribution).The TIC curve was analyzed by software to calculate the quantitative parameters,including baseline intensity(BI),arrival time(AT),time to peak(TTP),peak intensity(PI),ascending slope(AS),half time of descent(DT/2),descending slope(DS)and area under the curve(AUC).The ratio of quantitative parameters of nodule to the peripheral thyroid parenchyma was used as the relative value,including TTP-ratio,PI-ratio,AUC-ratio,AS-ratio,DS-ratio,DT/2-ratio.The number of relative value>1 and<1 were recorded.Chi-square test was used to compare the CUES characteristics and relative quantitative parameters between the group A and B.Independent sample t test was used to compare the quantitative parameters of group A and B.ResultsThere were 84 nodules in group A,96.4%(81/84)showed low enhancement,3.6%(3/84)showed equal or high enhancement,48.8%(41/84)showed inhomogeneous enhancement,51.2%(43/84)showed homogeneous enhancement,48.8%(41/84)showed centripetal enhancement and 51.2%(43/84)showed mixed enhancement.There were 45 nodules in group B,82.2%(37/45)showed low enhancement,17.8%(8/45)showed equal or high enhancement,82.2%(37/45)showed inhomogeneous enhancement,17.8%(8/45)showed homogeneous enhancement,37.8%(17/33)showed centripetal enhancement,and 62.2%(28/33)showed mixed enhancement.The intensity of enhancement and homogeneity of thyroid carcinoma in group A and group B were significantly different(p<0.05).There was no significant difference in enhancement mode between the two groups(p>0.05).Among the quantitative parameters,the AT of group A(?lcm)was earlier than that of group B(>1cm),and the TTP of group A(?1cm)was later than that of group B(>1cm),the difference was statistically significant(<0.05).There was no significant difference in PI,DT/2,AS,DS and AUC between group A and group B(p>0.05).Relative values of TTP-ratio,PI-ratio group A and group B were significantly different(p<0.05),and PI-ratio,DT/2-ratio,AS-ratio,DS-ratio and AUC-ratio between the two groups had no significant difference(p>0.05).ConclusionsPTC have different characteristics of CEUS,which is correlated with the size of tumor.Among the quantitative parameters of TIC,AT,TTP,TTP-ratio and PI-ratio is correlated with tumor size,while the other parameters have no relationship with tumor size.