The axillary lymph node status is the most important prognostic factor in breast cancer, and the axillary dissection as the gold standar for staging. It requires radical surgery, which is accompanied by importants postoperaive problems. Axillary lymph nodes can be imaged with a wide variety of available diagnostic radiological test (ultrasonography, mammography, computed tomography and magnetic resonance imaging). In these anatomic imaging, the limph nodes whit metastatic disease appear dense, enlarged or spiculated. Difficulties arise, not in visualization of the axillary lymph nodes, but in reliably separating normal from those involved with metastatic disease. Radionucleide studies and positron emisión tomography provide biochemical information, but are limited by resolution constrains.