140 Background: Sentinel lymph node biopsy (SLNB) is a more sensitive and accurate nodal staging procedure than axillary lymph node dissection (ALND). Because of detailed pathologic evaluation in SLNs, more nodal micrometastases have been identified. However, it remains controversial whether to perform 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 1,012 clinically node-negative, T1-T2 breast cancer patients, who underwent SLNB from January 2002 to Dec 2010 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. Intraoperative frozen examination was performed with hematoxylin and eosin (HE) staining. SLNs, fixed and embedded in paraffin, were additionally diagnosed with HE staining and immunohistochemical (IHC) analysis. Results: Micrometastases in SLNs were found in 69 (6.8%) of 1,012 patients. Thirty eight (55.1%) of 69 patients with micrometastatic SLNs underwent immediate or delayed ALND and revealed no NSLN metastasis. Among 31 (44.9%) patients with micrometastatic SLNs who omitted ALND and axillary radiation therapy, no axillary lymph node recurrence has been observed after a median follow-up of 50 months, although 29 patients (93.5%) in these 31 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 micrometastatic SLNs and the presence of micrometastases in SLNs may not worsen prognosis with proper systemic therapy.
Omission of axillary lymph node dissection after positive sentinel lymph node: Validity and safety among early breast cancer patients treated with mastectomy
