Axillary dissection vs no axillary dissection in women with invasive breast cancer and sentinel node metastasis: A randomized clinical trial JAMA, 02/09/2011

Giuliano AE et al. – The objective of this study was to determine the effects of complete axillary lymph node dissection (ALND) on survival of patients with sentinel lymph node (SLN) metastasis of breast cancer. Among patients with limited SLN metastatic breast cancer treated with breast conservation and systemic therapy, the use of SLND alone compared with ALND did not result in inferior survival.

• The American College of Surgeons Oncology Group Z0011 trial, a phase 3 noninferiority trial conducted at 115 sites and enrolling patients from May 1999 to December 2004
• Patients were women with clinical T1-T2 invasive breast cancer, no palpable adenopathy, and 1 to 2 SLNs containing metastases identified by frozen section, touch preparation, or hematoxylin-eosin staining on permanent section
• Targeted enrollment 1900 women with final analysis after 500 deaths, but trial closed early because mortality rate lower than expected
• All patients underwent lumpectomy and tangential whole-breast irradiation
• Those with SLN metastases identified by SLND were randomized to undergo ALND or no further axillary treatment
• Those randomized to ALND underwent dissection of 10 or more nodes
• Systemic therapy was at discretion of treating physician
• OS was primary end point, with noninferiority margin of 1-sided HR of less than 1.3 indicating that SLND alone is noninferior to ALND
• DFS was secondary end point

• Clinical and tumor characteristics were similar between 445 patients randomized to ALND and 446 randomized to SLND alone
• However, the median number of nodes removed was 17 with ALND and 2 with SLND alone
• At median follow-up of 6.3 years (last follow-up, March 4, 2010), 5-year overall survival was 91.8% (95% CI, 89.1%-94.5%) with ALND and 92.5% (95% CI, 90.0%-95.1%) with SLND alone; 5-year DFS 82.2% (95% CI, 78.3%-86.3%) with ALND and 83.9% (95% CI, 80.2%-87.9%) with SLND alone
• HR for treatment-related OS 0.79 (90% CI, 0.56-1.11) without adjustment and 0.87 (90% CI, 0.62-1.23) after adjusting for age and adjuvant therapy