Unusual aggressive breast cancer: metastatic malignant phyllodes tumor.

For the year of 2012, it has been estimated that breast cancer will account for the greatest number of newly diagnosed cancers and the second highest proportion of cancer related deaths among women. Breast cancer, while often lumped together as one disease, represents a diverse group of malignancies with different imaging findings, histological appearances and behavior. While most invasive primary breast cancers are epithelial derived adenocarcinomas, rare neoplasms such as the phyllodes tumor may arise from mesenchymal tissue. Compared to the breast adenocarcinoma, the phyllodes tumor tends to affect a younger population, follows a different clinical course, is associated with different imaging and histological findings and is managed distinctively. There may be difficulty in differentiating the phyllodes tumor from a large fibroadenoma, but the mammographer plays a key role in reviewing the clinical and imaging data in order to arrive at the correct diagnosis. Early diagnosis with proper surgical management can often cure non-metastatic phyllodes tumors. However, in rare cases where metastasis occurs, prognosis tends to be poor. This report describes the presentation, imaging findings and management of a metastatic malignant phyllodes tumor.