A follow-up to a study showing the noninferiority of sentinel lymph node dissection to axillary lymph node dissection for breast cancer in overall and disease-free survival at a median of 6.3 years found similar noninferiority in overall survival at 10 years.
Axillary lymph node dissection has a risk of complications including lymphedema, numbness, axillary web syndrome, and decreased upper-extremity range of motion. The American College of Surgeons Oncology Group Z0011 trial sought to determine if the procedure could be avoided without inferior survival outcomes.
Criticism of the study focused on the potential for later recurrence, particularly in patients with hormone receptor–positive breast cancer. All enrolled patients had one or two sentinel nodes with metastases. At randomization, 436 received sentinel lymph node dissection alone, and 420 received the additional axillary lymph node dissection. The patients were assessed every 6 months for the first 3 years, then annually.
After a median of 9.3 years, 110 of the patients had died of any cause – 51 in the sentinel lymph node dissection group and 59 in the axillary lymph node dissection group – a 10-year overall survival rate of 86.3% and 83.6%, respectively. This met the study’s primary endpoint of showing noninferior overall survival without the riskier procedure. In the study’s secondary endpoint, disease-free survival, there was not a significant difference either (80.2% vs. 78.2%).
“Axillary dissections are associated with considerable morbidity, and the results of this trial demonstrated that this morbidity can be avoided without decreasing cancer control. … These findings do not support routine use of axillary lymph node dissection in this patient population based on 10-year outcomes,” wrote Armando E. Guiliano, MD, of Cedars-Sinai Medical, Los Angeles and his coauthors (JAMA. 2017;318[10]:918-26. doi: 10.1001/jama.2017.11470).