Removal of two sentinel nodes accurately stages the axilla in breast cancer

Background: Assessment of lymph node status in breast cancer is still necessary for staging. Sentinel lymph node biopsy (SNB) may provide accurate staging with less morbidity than axillary clearance. The aim of this study was to assess the effect of the number of sentinel nodes removed on the false-negative rate. Methods: Data were collected prospectively from 395 women undergoing SNB for breast cancer, between June 1995 and December 2001. All nodes that were hot and/or blue were removed and analysed. Results: During this interval 136 patients who had SNB were lymph node positive. The median number of sentinel nodes removed was two (range one to five). The overall false-negative rate of SNB in these women was 7.1 per cent. If only one sentinel node had been removed, the false-negative rate would have been 16.5 per cent. The removal of more than two nodes had no effect on axillary staging in all but two women. Conclusion: In early breast cancer, when there were multiple sentinel nodes, removal of two sentinel nodes significantly reduced the false-negative rate compared with removal of one node. Removing more than two sentinel nodes did not significantly reduce the false-negative rate further.