Sentinel lymph node dissection for breast cancer: how many nodes are enough and which technique is optimal?

Background Controversy exists in sentinel lymph node (SLN) mapping in breast cancer regarding the appropriate number of nodes to remove and the best technique for identification of the SLNs. Methods A retrospective chart review from January of 1999 to January of 2004 was performed for all patients undergoing a SLN biopsy examination who had at least 1 positive SLN. Results We identified 167 patients. A mean of 4.4 SLNs were removed per patient. All of the positive SLNs were identified by node 6. Radiotracer used alone identified 19 positive nodes (11.4%) and blue dye used alone identified 14 positive nodes (8.4%). Conclusions Our data show that 100% of positive SLNs are found by 6 nodes removed, thereby supporting the concept that the SLN dissection may not be complete by removing only 1 or 2 nodes or only the hottest node. The use of blue dye or radiotracer alone can contribute to the overall false-negative rate.