Mammographically non-calcified ductal carcinoma in situ: sonographic features with pathological correlation in 35 patients.

AIM To present the sonographic findings of mammographically non-calcified ductal carcinoma in situ (DCIS) with histopathologic correlation. MATERIALS AND METHODS The mammographic and ultrasonographic presentations of 47 radiographically non-calcified DCIS lesions in 35 patients were retrospectively analysed. Histological characteristics (architectural appearance, nuclear grade, percent of involved lobules, and presence of necrosis) were reviewed. RESULTS Seventeen lesions were not mammographically visible (17/47, 36%). Ultrasonographically, these lesions showed an irregular shape (28/47, 60%), microlobulated margins (34/47, 72%) and abrupt interfaces (42/47, 90%). Only 11% (5/47) displayed posterior shadowing. The echotexture of these lesions was most frequently complex (29/47, 62%); therefore, they were divided into two types: type I (24 cases), which were predominantly solid with cystic components, and type II (five cases), which were predominantly cystic with a solid intra-cystic component. A trend to have greater than 50% DCIS cells in cancerous lobules was observed in masses displaying type I echotexture (difference=36%, 95% confidence interval 10.6-62.5) and microlobulated margins (difference=32%, 95% confidence interval 5.1-58.7). CONCLUSION Ultrasonographically detected radiographically non-calcified DCIS commonly displays an irregular shape, microlobulated margins, and complex echotexture, giving a "pseudomicrocystic" appearance. Microlobulated margins and "pseudomicrocystic" echotexture seem to be associated with a cancerization of the lobules.