Age and Receptor Status Do Not Indicate the Need for Axillary Dissection in Patients with Sentinel Lymph Node Metastases

Abstract

Background ACOSOG Z0011 demonstrated the safety of omitting axillary dissection (ALND) in women with <3 positive sentinel lymph nodes (SLNs) undergoing breast-conservation therapy (BCT). Since most were postmenopausal with ER-positive cancers, applicability to younger patients or those with triple-negative (TN) or HER2 overexpressing (HER2+) tumors remains controversial. Methods From 8/2010–12/2015, patients undergoing BCT for cT1-2N0 disease and found to have positive SLNs were prospectively followed. ALND was indicated for >2 positive SLNs or gross extracapsular extension. Clinicopathologic characteristics, axillary surgery, nodal burden, and outcomes were compared between high-risk (TN, HER2+, or age<50 years), and the remaining patients, termed average-risk. Results Among 701 consecutive patients, 242 (35%) were high-risk: 31 (13%) TN, 48 (20%) HER2+, 130 (54%) age<50, and 33 (14%) >1 high-risk feature; 459 (65%) were average-risk. High-risk patients were younger, with higher-grade tumors (p<0.0001), and more often had abnormal nodes imaged (p=0.02). SLNB alone was performed in 85% high-risk vs. 82% average-risk cases (p=0.39): median 4 vs. 3 SLNs excised (p=0.04), and median of 1 positive SLN in both groups. 62% high-risk vs. 65% average-risk (p=0.8) had additional positive nodes at ALND, with a median of 3 positive nodes in both groups. At median follow-up of 31 months, there were no isolated axillary recurrences. Conclusions ALND was no more likely to be indicated in high-risk patients. In patients undergoing ALND, nodal burden was similar. ALND is not indicated based upon age or subtype in patients otherwise meeting Z0011 clinical eligibility criteria.

The Optimal Treatment Plan to Avoid Axillary Lymph Node Dissection in Early-Stage Breast Cancer Patients Differs by Surgical Strategy and Tumor Subtype

“…Interestingly, the utilization of NAC to maximize the likelihood of sparing an ALND is not a “one size fits all” approach. While rates of ALND have not been shown to differ by tumor subtype among women undergoing upfront BCS and managed according to Z0011 24 , rates of nodal pCR following NAC differ substantially by subtype.…”

Effect of Axillary Dissection vs No Axillary Dissection on 10-Year Overall Survival Among Women With Invasive Breast Cancer and Sentinel Node Metastasis

“…Among 701 consecutive patients with node-positive tumors at Memorial Sloan Kettering Cancer Center who met ACOSOG Z0011 eligibility criteria, 83% did not have to undergo ALND. 19 In a 12-hospital network, use of ALND decreased from 71% to 17% after development of a guideline using ACOSOG Z0011 eligibility criteria and age of 50 years or older as indications for SLND alone. 20 …”

Axillary Nodal Management Following Neoadjuvant Chemotherapy

“…52 Subsequently, the same group reported a cohort of 701 consecutive cT1-2N0 patients with a positive SLN and found no difference in the likelihood of ALND among high-risk patients, defined as women 50 years of age or younger, or with triple-negative or HER2 amplified tumors compared to postmenopausal women with estrogen receptor positive cancers, with 13% and 12% of each group having ≥3 positive SLNs (p=0.82). 53 While these results indicate a minority of cN0 women undergoing breast-conserving therapy require ALND, it may be possible to reduce this rate among selected patients, and, importantly, these results do not apply to women undergoing mastectomy. Rates of nodal pCR with NAC differ based on tumor subtype 18 , ranging from 40% to 60% overall, and approaching 70% to 80% among patients with triple-negative and HER2 amplified tumors (Table 5).…”