Sentinel lymph node biopsy in breast cancer.

The clinical management of breast cancer has improved tremendously in the last 2 decades. Sentinel lymph node biopsy (SNB) allows conservation of the axillary lymph nodes in most patients who have breast cancer. Furthermore, it allows identification of occult nodal disease after step sectioning and more detailed staging. Although large breast tumors, multicentric disease, recurrent cancers, and use of neoadjuvant therapy were previously considered contraindications to SNB, a large body of evidence is accumulating to support its use in these cases. The prognostic significance of micrometastases and isolated tumor cells needs clarification in prospective, randomized trials.