Axillary lymph node metastases in breast cancer: preoperative detection with dynamic contrast-enhanced MRI

Metastatic involvement of axillary lymph es is one of the most important pr ognostic varies in breast cancer. The aim of our work was to study the valu e of dynamic contrast-enhanced MR imaging in revealing axillary lymph node metastases from breast cancer. A total of 65 patients with invasive breast cancer treated with axillary lymph node section were preoperatively evaluat ed by MRI. T1-weighted dynamic contrast-enhanced 3D images were acquired us ing a coil covering the breast and the axilla, The dynamic contrast enhance ment, size, and morphology of the axillary lymph nodes were registered. His topathological examination revealed axillary lymph node metastases in 24 pa tients. When using a signal intensity increase in the lymph nodes of > 100% during the first postcontrast image as a threshold for malignancy, 57 of 6 5 patients were correctly classified (sensitivity 83 %, specificity 90 %, a ccuracy 88%). These results were not improved when lymph node size and morp hology were used as additional criteria. Axillary lymph nodes can be evalua ted part of an MR-mammography study without substantial increase in examina tion time, and provide the surgeon with knowledge about the localization of le metastatic lymph nodes.