RÉSUMÉ
PURPOSE: The aims of this study were to examine the feasibility of sentinel lymph node (SLN) biopsy using the day-before-surgery or the same-day subareolar injection of (99m)Tc-Tin colloid, and to evaluate the accuracy of performing intraoperative multiple frozen section diagnosis of the SLN for breast cancer. METHODS: From Jul. 2003 to Feb. 2004, a total of 81 women with clinically node negative breast cancer underwent SLN biopsy and this was followed by axillary lymph node dissection at the Korea Cancer Center Hospital. 2-2.5mCi of (99m)Tc-Tin colloid was injected intradermally in the outer upper edge of the areola on the day before or the same day of surgery, and lymphoscintigraphy was then obtained. The time interval between the injection of tracer and SLN biopsy varied from 1 hour to 20 hours. Intraoperatively, the status of the SLNs was examined by multiple frozen section diagnosis and all the SLNs were subjected to serial sectioning for Hematoxylin-eosin staining and immunohistochemical staining for cytokeratin. After removal of the SLNs, standard level I and II axillary dissection was performed in all patients. RESULTS: In 26 patients (32.1%), the SLNs were positive for tumor cells among these 26 patients. 16 patients (61.5%) results showed that the SLNs were the only metastatic nodes. Two cases of false negative findings were identified. The sensitivity and specificity were 92.9% and 100% respectively. In the second half of this study, no false-negative cases were found in 41 consecutive patients. CONCLUSION: The results of SLN biopsy using the day-before-surgery or same-day subareolar injection of (99m)Tc-Tin colloid were excellent for identification of the SLNs. This technique does not interfere with effective treatment in the operating room because the time interval between the injection and surgery did not affect the results of SLN biopsy. Intraoperative multiple frozen section diagnosis of SLNs was readily available, and this was highly accurate for assessing the status of SLNs