The Feasibility and Accuracy of the Sentinel Lymph Node Biopsy for Breast Carcinoma

Abstract

As the procedure of sentinel lymph node biopsy for breast cancer becomes more widely available, the practicality of it in the hands of general surgeons should be assessed. This is a study of the accuracy and use of this procedure. A prospective study was conducted at two university-affiliated teaching hospitals. Ninety-one patients with invasive breast cancer were enrolled in the study. Twelve patients were excluded from analysis. The remaining 79 patients were injected peritumorally with technetium-99m-labeled sulfur colloid and isosulfan vital blue dye. The sentinel lymph node was located and excised using a gamma probe, and the definitive breast cancer operation was completed, including an axillary dissection. Histology of the sentinel lymph node specimen was compared with that of the axilla. Sentinel lymph nodes were located in 64 (81.0%) of the 79 patients. Sentinel lymph nodes and axillary nodes were benign in 44 (68.8%) of the 64 patients; these patients could potentially have been spared the axillary dissection. Fourteen (21.9%) patients had metastatic cancer to the sentinel nodes only, and five (7.8%) patients had axillary metastasis beyond the sentinel lymph node. Among the 64 patients, there was one false negative. Sensitivity and specificity when a sentinel lymph node was found were 95.0 per cent and 100 per cent, respectively. The sentinel lymph node accurately predicted the axillary contents 98.4 per cent of the time. This study demonstrates that the sentinel lymph node can be identified and is reliable in predicting axillary node status. This study also shows that the procedure has a notable learning curve, but can be used by general surgeons with a commitment to the care of breast cancer patients.