Comparison of sentinel lymph node biopsy alone and completion axillary lymph node dissection for node-positive breast cancer

Purpose: For women with breast cancer, the role of completion axillary lymph node dissection (ALND) after identification of nodal metastases by sentinel lymph node biopsy (SLNB) has been questioned. Our objectives were to assess national nodal evaluation practice patterns and to examine differences in recurrence and survival for SLNB alone versus SLNB with completion ALND. Patients and Methods: From the National Cancer Data Base (1998 to 2005), women with clinically node-negative breast cancer who underwent SLNB and who had nodal metastases were identified. Practice patterns and outcomes were examined for patients who underwent SLNB alone versus SLNB with completion ALND (median follow-up, 63 months). Results: Of 97,314 patients, 20.8% underwent SLNB alone, and 79.2% underwent SLNB with completion ALND. In 2004 to 2005, patients were significantly more likely to undergo SLNB alone if they were older, had smaller tumors, or were treated at non-National Cancer Institute-designated cancer centers. In patients with macroscopic nodal metastases (n = 20,075 during 1998 to 2000), there was a nonsignificant trend toward better outcomes for completion ALND (v SLNB alone) after analysis was adjusted for differences between the two groups: axillary recurrence (hazard ratio [HR], 0.58; 95% CI, 0.32 to 1.06) and overall survival (HR, 0.89; 95% CI, 0.76 to 1.04). In patients with microscopic nodal metastases (n = 2,203 during 1998 to 2000), there were no significant differences in axillary recurrence or survival for patients who underwent SLNB alone versus completion ALND. Conclusion: Compared with SLNB alone, completion ALND does not appear to improve outcomes for breast cancer patients with microscopic nodal metastases; however, there was a nonsignificant trend toward better outcomes with completion ALND for those with macroscopic disease.