Selective sentinel lymphadenectomy for breast cancer in the United States.

Lymph node status is the most reliable prognostic indicator for breast cancer patients. Sentinel lymph nodes (SLNs) are the first draining lymph nodes for metastatic breast cancer to spread from the primary site. Although the therapeutic role of selective sentinel lymphadenectomy (SSL) in breast cancer has not been determined, the practical significance is that it is being used as a staging procedure, so that a negative SLN can spare a patient more extensive axillary lymph node dissection (ALND) with its associated morbidity. If the SLN is negative, the negative predictive value of the remaining nodal basin for breast cancer exceeds 95%. SSL selects out one or a few SLNs and permits more extensive study of the nodes by the pathologist. Such extensive examination would not be practical for the many nodes yielded by a standard ALND. SSL is rapidly evolving into a standard approach for staging primary breast cancer in the United States, without the maturation of results from clinical trials.