Non-sentinel lymph node status and prognosis of the breast cancer patients with micrometastatic sentinel lymph nodes

Abstract

e11504 Background: Sentinel lymph node biopsy (SLNB) has become a standard therapy for clinically node-negative breast cancer patients and improvements of histopathological and molecular analysis of sentinel lymph node (SLN) have increased the rate of micrometastases identified. However it remains controversial whether to perform axillary lymph node dissection (ALND) for patients with micrometastases in SLNs and their prognostic significance is also a matter of debate. The purpose of this study is to determine the non- sentinel lymph node (NSLN) status and prognosis of the patients with micrometastatic SLNs. Methods: A prospective database of 666 breast cancer patients with the tumor size less than 3cm and clinical negative node, who underwent SLNB from January 2002 to July 2007 at Keio University Hospital was analyzed. SLNs were detected using a combined method of isosulfun blue dye and small-sized technetium-99m-labeled tin colloid. SLNs were diagnosed with standard hematoxylin and eosin (HE) staining and immunohistochemical (IHC) analysis. Results: Micrometastases in SLNs were found in 50 (7.5%) of 666 patients. Twenty nine (58.0%) of 50 patients with micrometastatic SLNs underwent ALND and revealed no NSLN metastasis. Among 21 (42.0%) patients with micrometastatic SLNs who skipped ALND, no axillary lymph node recurrence has been observed in the median follow-up time of 43 months, although 20 patients (95.2%) in 21 patients received adjuvant systemic therapy. There is no significant difference in recurrence free survival between the patients with micrometastatic and negative SLNs (98.0% vs. 95.7%, respectively). Conclusions: These date suggested that it may not be necessary to perform ALND for the patients with micrometastases in SLNs and the presence of micrometastases in SLNs may not be associated with prognosis. No significant financial relationships to disclose.