Ultrasound examination is useful for prediction of histologic type in invasive ductal carcinoma of the breast

The aim of this study was to estimate the histologic type of invasive ductal carcinoma of the breast according to the ultrasound (US) criteria and to identify the high-risk patients for lymph node metastases. An acceptable preoperative diagnosis of lymph node metastasis is essential when performing the reduction of lymphadenectomy. The positive relationship between histology and prognosis has been reported in breast cancer. However, few reports have examined the relationship between preoperative US findings and histology. Ultrasound examination was performed in 252 patients with invasive ductal carcinoma (91 papillotubular, 54 solid-tubular and 107 scirrhous carcinoma). Risk factors for nodal metastasis were analyzed in clinicopathological findings. After nine criteria were defined based on US findings, all tumors were classified into US histologic type. According to the multivariate analysis, lymph node metastases was significantly associated with tumor size (p < 0.001), histology (p < 0.001) and age (p = 0.038). Histology was an important risk factor for nodal metastasis, especially in scirrhous carcinoma. When comparing the US classification and histology, the accuracy rate of US for papillotubular, solid-tubular and scirrhous type was 75%, 78% and 75%, respectively. To predict the scirrhous carcinoma with frequent nodal metastasis, US criteria such as the larger ratio of depth-to-width, boundary echo and attenuation of the back echo was important. It is important to preoperatively estimate the histologic type by tumor property using US. Our US classifications may be useful to pick up high-risk patients for nodal metastasis in invasive breast cancer.