Ultrasonographic findings of papillary thyroid carcinoma and their relation to pathologic changes.

To elucidate the ultrasonographic findings in papillary thyroid carcinoma and their relation to pathologic changes, 47 patients on whom thyroid ultrasonography had been performed and whose thyroid tissues were pathologically proven to be papillary thyroid carcinoma were studied. The ultrasonographic findings were reviewed and correlated with the pathologic changes. Fifty-three out of 94 thyroid lobes had papillary carcinoma. The ultrasonographic features of the affected thyroid lobes were hypoechoic in 46, isoechoic in 6 and hyperechoic in 1. The ultrasonographic texture of all 53 lesions was heterogeneous. The margin was clear in 11 lesions and unclear in 42. Cystic degeneration was found in 15 lesions. Discrete particles representative of microcalcifications were found in 25 lesions. Halo signs were found in 7 lesions. Lymph node enlargement was detected in 4 cases. The sensitivity and specificity of each ultrasonic finding in predicting the respective pathologic feature were: unclear margin for tumor invasion, 84% and 31%; cystic degeneration for cysts, 42% and 79%; discrete particles for microcalcification, 50% and 52%; halo sign for total encapsulation, 42% and 88%; and lymph node enlargement for lymph node metastasis, 18% and 100%, respectively. These data suggest that ultrasonographic findings in papillary carcinoma were usually hypoechoic and heterogeneous. An unclear margin in sonography is fairly sensitive for the prediction of tumor invasion.