Sentinel node biopsy in the staging of breast cancer.
BACKGROUND: The role of axillary lymph node dissection (ALND) in breast cancer is currently being reevaluated. Sentinel node biopsy (SNB) holds promise for replacing full dissection in a large number of patients with breast cancer. MATERIALS: We evaluated SNB utilizing an intraoperative gamma probe localization technique following injection of technetium sulfur colloid in 80 patients with primary breast cancer and clinically negative axillae. Forty-eight patients were evaluated at Baptist Medical Center, Montgomery, Alabama, and 32 at Rush-Presbyterian-St. Luke's Medical Center in Chicago, Illinois. RESULTS: At least one sentinel node was found in 70 of the 80 patients (88%). One patient had a sentinel node in both the axilla and internal mammary chain. The remainder had axillary sentinel nodes only. The sentinel nodes accurately predicted the status of the axilla in 69 of the 70 patients (99%). One of 14 node-positive patients would have been missed with sentinel node biopsy alone, for a false negative rate of 7%. Four node-positive patients would have been missed with routine ALND without serial sectioning (SS) and immunohistochemical staining (IH) of the sentinel node. CONCLUSIONS: Sentinel node biopsy with SS and IH more precisely predicted the status of the axilla than routine ALND in this group of patients. SNB will likely replace full axillary dissection in the majority of patients with breast cancer.