Metastatic intramammary lymph nodes: mammographic and ultrasonographic features

To evaluate the mammographic and ultrasonographic findings in patients with intramammary lymph node (IMLN) involvement in breast cancer.

The mammograms of 1655 histopathologically proven breast cancer cases diagnosed during the last 10 years were retrospectively reviewed. There were 16 cases in which metastasis to intramammary lymph nodes was suspected mammographically and proven histopathologically. The clinical and radiological features of these 16 cases were evaluated.

On mammograms, the involved lymph nodes were all well circumscribed, homogeneous, oval or round opacities in the upper outer quadrant of the breast. They were all larger than 1 cm in size. On US, they were seen as well circumscribed, homogeneously hypoechoic masses with mild acoustic enhancement. In one case, besides enlargement, development of malignant microcalcifications was seen inside the node in the follow up period. In another case with IMLN metastasis, the primary focus of the breast cancer could not be detected either mammographically or histopathologically. So the case was accepted as occult breast carcinoma. All of the primary tumors detected were invasive histopathologically and their sizes varied between 1-6 cm (mean, 3 cm).

The involvement of the IMLN can be suspected with mammographic and ultrasonographic features. Metastatic disease from breast cancer to IMLN may be the first clinical and/or radiological sign of breast cancer.