Sensitivity of Sentinel Lymph Node Biopsy in Breast Cancer Patients: Preliminary Report

Abstract

Objectives: To study the identification rate, the sensitivity, and the false negative rate of sentinel lymph node biopsy (SLNB) in determining axillary nodal metastasis from breast cancer.

Methods: Fifty breast cancer patients who were to be treated from January 1, 2007-July 31, 2009 and had non-palpable axillary lymph node (ALN) were included in the study. The sentinel lymph node was identified by subdermal injection of 2 ml blue dye solution (1% isosulfan blue dye 2 ml plus normal saline 2 ml) over the tumor and 2 ml at subareolar area. Gentle massage was done for 5-10 minutes before biopsy of a dye-taken node followed by axillary lymph nodes dissection (ALND). The SLN and other axillary lymph nodes were submitted separately for histopathologic examination.

Results: Mean age of the patients was 52.6 ฑ 12.2 years old. Most of them (42.0 %) were in stage 2. Mean tumor size at the time of surgery was 2.4 ฑ 1.2 cm. The identification rate of SLNB was 96.0% (48 cases). Regarding 24 cases who had negative SLN, no one had positive ALN or there was no false negative with the sensitivity of 100%. In those 24 cases who had positive SLN, ALN were negative in 11 cases (45.8%) and positive in 13 cases (54.2%). Those 2 patients who failed SLNB, 1 had positive and 1 had negative ALN.

Conclusion: The identification rate and the sensitivity of SLNB was high with no false negative cases. The procedure should be performed instead of ALND in early breast cancer patients who had non-palpable ALN.

Keywords: sentinel lymph node biopsy, breast cancer, isosulfan blue dye