Detection of intraductal component around invasive breast cancer using ultrasound: correlation with MRI and histopathological findings.

PURPOSE: The purpose of this study was preoperatively to diagnose the intraductal component, which is indispensable in planning for breast conservation therapy, and also to minimize local recurrence. This study investigated the efficacy of ultrasound (US) in the detection of intraductal component in comparison with magnetic resonance imaging (MRI) and histopathological findings. PATIENTS AND METHODS: In 47 patients with invasive breast cancer, US features of the intraductal component were classified as (a) solid ductal dilatation radiating from the tumor, (b) presence of satellite lesion in the same segment without ductal dilatation, and (c) ductal dilatation between the main tumor and satellite lesion. MRI depicted intraductal extension as the most enhanced area during the first or second phase of the dynamic study. Other criteria for the detection of the intraductal component by MRI were as follows: (a) a satellite lesion around the main tumor, (b) bridging enhancement between the main tumor and satellite lesions. The extent of the intraductal component was measured and classified as mimimal (0-5 mm), moderate (6-15 mm) or wide (>15 mm).
RESULTS: In 28 of 47 (60.0%) patients, a wide intraductal component of more than 15 mm was proved histopathologically. Of 28 patients, US and MRI could accurately detect wide intraductal components in 16 patients and 14 patients, respectively. Sensitivity, specificity, and accuracy were 57.1%, 84.2%, and 68.1% respectively for US and 50.0%, 89.5% and 65.9% for MRI, respectively. When both US and MRI results were combined, sensitivity, specificity, and accuracy were 75.0%, 84.2%, and 78.7%.
CONCLUSION: Current US examination depicted the intraductal component of breast cancer more accurately than MRI. Further, our study suggests that the use of both US and MRI together is complementary and offers more advantage than US alone.