SENTINEL LYMPHADENECTOMY FOR BREAST-CANCER IN A COMMUNITY MANAGED CARE SETTING

PURPOSE To evaluate the feasibility, accuracy, and reproducibility of intraoperative lymphatic mapping and sentinel lymphadenectomy (IOLM/SL ) in the staging of breast cancer patients in a community managed care setting. PATIENTS AND METHODS One hundred forty-five patients with pr imary breast cancer were prospectively studied over a 26-month period. They underwent vital dye injection at their primary breast cancer sit e. Lymphatic channels were traced to the sentinel lymph node, which wa s excised, serially sectioned, and examined. A level I and II axillary lymph node dissection and definitive breast surgery were then perform ed. RESULTS Sentinel nodes were identified in 103 of 145 procedures (7 1.0%). Sentinel and nonsentinel lymph nodes were concordant in 100 of 103 cases (97.1%). Three patients (9.7%) had falsely negative sentinel nodes; there were none in the last 80 patients. Of 28 positive sentin el nodes, 12 (42.9%) represented the only tumor-containing node within the axilla. Sentinel nodes were significantly more likely to contain tumor than nonsentinel nodes (33/50, 66.0% vs 54/467, 11.6%, P < 0.000 1). IOLM/SL identified more micrometastases (< 2 mm) than standard axi llary lymph node dissection (13/33, 39.6% vs 4/177, 2.2%, P < 0.001). Nine of 42 patients (21.4%) whose sentinel node could not be identifie d had five or more nodal metastases. Two of six patients with presumed Tis primaries had nodal metastases. DISCUSSION IOLM/SL accurately ide ntifies the sentinel lymph node(s) most likely to contain metastatic d isease. A procedural learning curve was present. An unsuccessful IOLM/ SL was a risk factor for considerable nodal metastases. IOLM/SL with a tumor-free sentinel node may obviate a formal axillary lymph node dis section. The technique was feasible, economical, and reproducible with in the context of a community managed care facility, while not placing exacting demands on operating room, pathology, or nuclear medicine pe rsonnel.