Low Locoregional Failure Rates in Selected Breast Cancer Patients with Tumor-positive Sentinel Lymph Nodes Who Do Not Undergo Completion Axillary Dissection

Background: The role for completion axillary dissection (CLND) in patients with breast cancer who have tumor-positive sentinel lymph nodes (SLN) has been questioned. The objective of this study was to examine the long-term safety of avoiding CLND in selected patients with positive SLNs.

Methods: Patients with invasive breast cancer who underwent SLN biopsy at the authors' institution between 1993 and July 2005 were reviewed. Of 3366 total patients, 750 patients had a positive SLN. There were 196 patients with a positive SLN who did not undergo CLND based on clinician and patient preference. Clinicopathologic variables and treatment patterns were analyzed along with locoregional, distant recurrence, and survival.

Results: Most tumors were infiltrating ductal carcinomas (74%), estrogen receptor-positive tumors (82%), progesterone receptor-positive tumors (70%), HER-2/neu-negative tumors (78.6%), and tumors were classified predominantly as either T1 or T2 (95.4%). The median number of SLNs removed was 3, and the median number of positive SLNs was 1. The median size of the tumor deposit in the SLN was 1.0 mm (range, 0.1-12.9 mm). Most SLNs were positive by on hematoxylin and eosin staining (64.3%), whereas 35.7% of SLNs were positive only by immunohistochemistry. Most patients underwent breast conservation (68.9%), radiation (58.2%), and chemotherapy (neoadjuvant in 14.3%, adjuvant in 55.6%). With a median follow-up of 29.5 months, no patients had an axillary recurrence, 1 patient had a supraclavicular lymph node recurrence, and 3 patients developed distant metastases. The median time to recurrence was 32 months.

Conclusions: In selected patients who had positive SLNs, the locoregional failure rate was low without CLND. Prospective studies will be valuable to corroborate these results and to refine further the optimal selection criteria for this approach.