Sentinel node biopsy in breast cancer

The concept of breast sentinel node biopsy is based on the assumption that a breast cancer that metastasizes through the lymphatics will initially rea ch one or a few nodes in the corresponding lymph basin. The status of this or these sentinel node(s) will predict the status of all the other nodes in the basin. The sentinel node can be found stained blue or as being radioac tive by injecting blue dye or a radioactive tracer around the tumour. Scint igraphy may further help to localize the sentinel node. The feasibility of the method has been validated by several studies comparing the status of th e sentinel node with the node status of the axilla revealed by subsequent a xillary clearance. Detection rates of 66-100% and false-negative rates of 1 7-0% have been reported. Before the method can be accepted for clinical use . a consensus concerning the accepted false-negative rate has to be reached and has to be shown in practice. From a theoretical point of view, a calcu lated false-negative risk rate of 2-3% can be accepted.