Objective. To determine the relative frequency of various sonographic findings in papillary carcinoma of the thyroid. Methods. We retrospectively analyzed the sonographic features in 55 patients with proven papillary carcinoma of the thyroid. Sonographic features analyzed were echo texture, cystic change, margin, contour, presence of a peripheral halo, vascularity, and calcification pattern. Features were classified as common (greater than or equal to35% of cases) or uncommon (<10% of cases). Combinations of features were also analyzed. Results. Common sonographic features of papillary carcinoma included hypoechoic texture (86%), microcalcifications (42%) or no calcifications (47%), well-defined margins (47%), and intrinsic hypervascularity (69%). Uncommon features included hyperechoic or mixed echo texture, cystic elements, irregular margins, hypovascularity, and coarse or peripheral calcifications. Of the 29 lesions that had calcifications, 20 (69%) had microcalcifications; 5 (17%) had coarse calcifications, and 1 had peripheral calcifications. In total, 54% of cases had at least 1 uncommon feature, and 11% had 2 or more uncommon features. Cystic carcinomas were rare and accounted for only 6% of lesions; all had hypervascular solid components. No carcinomas in our series were completely avascular. Conclusions. There is a broad spectrum of sonographic findings in papillary carcinoma of the thyroid. Half of the lesions in this series had at least 1 uncommon sonographic feature.
