Value of sentinel node biopsy in the management of breast cancer

To determine the rate of detection of the sentinel node using both blue dye and radioisotope, and the accuracy with which the sentinel node histology reflects the nodal status of the axilla in a series of patients with clinically node-negative breast cancer.

During a 32-month period from May 1998 to December 2000, 73 patients with clinically node-negative breast cancer underwent sentinel node biopsy immediately followed by formal axillary lymphadenectomy. The sentinel node(s) was identified using a combination of lymphoscintigraphy, blue dye and an intraoperative hand-held gamma probe.

The mean age of the 73 patients was 58 years (range 32-83 years). Twenty-six per cent (19/73) had previous surgical/excisional biopsy. Pre-operative lymphoscintigraphy was positive in 74% (54/73) of patients. Combination of blue dye and radioisotope was better than either method in isolation for identifying the sentinel node, yielding a success rate of 96% (70/73). A total of 32 cases proved to have positive nodal disease on histological examination. In 44% (14/32) of patients, the sentinel node was the only positive node. Forty-seven per cent (15/32) of patients in whom the sentinel node was positive also had positive nodes in the axillary nodal basin. There were 3/32 false negative cases, giving a false negative rate of 9.4%.

Sentinel node biopsy will have a role in the management of breast cancer. However, widespread adaptation of this technique awaits the results of prospective, randomised trials.