Sentinel Node Biopsy: Standard of Care

Abstract

Abstract: Sentinel lymph node biopsy (SLNB) is a less invasive alternative to axillary lymph node dissection (ALND) for staging breast cancer. In appropriate women, this procedure can stage the axilla with less extensive surgery and fewer complications. Sentinel node status is accurate in predicting axillary status based on single institutional experiences and confirmed by large multi-center trials. Non-sentinel nodes are involved very rarely if the sentinel node is tumor-free. SLNB enables intense examination of a single lymph node. However, the use of special stains to detect micrometastases is of uncertain clinical significance and is the subject of large trials. Early follow-up from the John Wayne Cancer Institute experience demonstrates excellent outcome for patients with either micrometastases or tumor-free nodes. Results from techniques with either blue dye or radioisotope colloid tracer and injection locations at peri-areolar, peritumoral, or subcutaneous sites are similar. These findings support the biological concept of a single (or very few) sentinel nodes for the entire breast. The sentinel node is more predictive of axillary status than any other tumor prognostic factor. Axillary lymph node dissection is unlikely to reveal nodal metastases when the sentinel node is tumor-free, and in such cases there is no reason to perform a completion axillary node dissection. Sentinel node biopsy alone without axillary lymph node dissection should now be the standard of care for most clinically node-negative women with breast cancer.