ULTRASONIC EVALUATION OF BENIGN AND MALIGNANT NODULES IN ECHOGRAPHICALLY MULTINODULAR THYROIDS

In 165 patients with ultrasound findings of multinodular thyroids in w hom thyroid resection was performed, sonographic features and pathohis tologic findings of removed nodules were analyzed. Of 426 nodules remo ved, 70 were carcinomas and 356 benign. Carcinomas are more often hypo echogenic (p < 0.01) and contain nodular calcifications (p < 0.01), wh ile benign nodules are more often iso-hyperechogenic (p < 0.01), showi ng intranodular cystic degenerative changes (p < 0.01) and perinodular hypoechogenic rim (p < 0.01). Mean diameter of carcinomatous nodules is lower than in benign nodules (p = 0.022). The relative proportion o f malignant nodules is highest in the upper halves of thyroid lobes (p < 0.01). Although certain sonographic signs increase the likelihood o f a given lesion being malignant or benign, the lack of absolute speci ficity in the ultrasound evaluation of thyroid nodules was confirmed. (C) 1994,John Wiley and Sons, Inc.