A new surgical technique, sentinel lymph node biopsy (SLNB), has been introduced into the management of breast cancer that can detect the lymph node most likely to contain metastatic disease. The hypothesis that the sentinel node(s) is the most likely node to contain metastatic disease has been proven for melanoma. If the sentinel node does not contain melanoma metastases, the probability that other nodes will be positive is negligible. Surgeons can now perform a simple node biopsy, instead of a complete lymph node dissection, with less morbidity and increased sensitivity of detecting metastatic disease. The small studies that have analyzed the potential of this technique in breast cancer to accurately detect metastatic disease can be criticized for (1) not finding the sentinel node in as many as 35% of patients, (2) including only patients with fine or core needle biopsy diagnosis, (3) using a wide variety of inconsistent techniques, and (4) analyzing the sentinel node using only histology. The overall goal of the project is to increase the accuracy and sensitivity of detecting metastatic disease as well as to determine the significance, in terms of survival, of this improved detection.

Part I: Clinical. A multi-institutional study has been started by the Principal Investigator investigating the accuracy of SLNB in the management of breast cancer. This study will determine: (1) the best candidates for SLNB; (2) variables affecting the success rate in finding the sentinel node; and (3) variables affecting its accuracy in predicting the presence of disease in the remaining lymph nodes.