The Extent of Extracapsular Extension May Influence the Need for Axillary Lymph Node Dissection in Patients with T1–T2 Breast Cancer

Abstract

Background Whether extracapsular extension of tumor (ECE) in the sentinel lymph node (SLN) is an indication for axillary dissection (ALND) in patients managed by ACOSOG Z0011 criteria is controversial. Here we examine the correlation between ECE in the SLN and disease burden in the axilla. Methods Patients meeting Z0011 clinicopathologic criteria (pT1-T2,cN0 with <3 positive SLNs) were selected from a prospectively maintained database (2006-2013). Chart review documented presence/extent of ECE. Neoadjuvant chemotherapy patients were excluded. Comparisons were made by presence/extent (≤2mm vs.>2mm) of ECE. Results Of 11,730 patients, 778 were pT1-T2, cN0 with <3 positive SLNs without ECE and 331 (2.8%) had ECE. Of these, 180 had ≤2mm, and 151 had >2mm ECE. Patients with ECE were older (57 vs54 yrs;p=0.001) and had larger (2.0cm vs 1.7cm,p<0.0001), multifocal (p=0.006), HR-positive tumors (p=0.0164), with LVI (p<0.0001). Presence and extent of ECE was associated with greater axillary disease burden; 20% and 3% of patients with and without ECE, respectively, had ≥4 additional positive nodes at cALND (p<0.0001) and 33% of patients with >2mm ECE had ≥4 additional positive nodes at cALND compared to 9% in the <2mm group(p<0.0001). On multivariate analysis,>2mm ECE was the strongest predictor of ≥4 positive nodes at cALND (OR 14.2). Conclusions Presence and extent of ECE were significantly correlated with nodal tumor burden at cALND, suggesting that >2mm of ECE may be an indication for ALND or RT when applying Z0011 criteria to patients with metastases in <3 SLNs. ECE reporting should be standardized to facilitate future studies.

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

“…ACOSOG Z0011 did not define a volume of microscopic extracapsular extension that mandated ALND, and this is often left to surgeon judgment. One study reported that >2mm of extracapsular extension was associated with a heavy nodal disease burden 33 ; however, need for ALND because of extracapsular extension remains an ongoing area of debate. Even with these limitations, we feel that the findings in this study will aid in counseling patients interested in optimizing avoidance of ALND.…”

Sentinel Lymph Nodes for Breast Carcinoma: A Paradigm Shift

“…79 Studies have shown that focal ECE is present in the SLNs of 19% to 30% of cN0 patients with early-stage breast carcinoma. 80–83 To date, the significance of microscopic ECE in SLNs in the selection of patients for ALND or axillary radiotherapy has not been thoroughly assessed. ACOSOG Z0011 excluded patients with matted nodes and gross ECE but had no specific policy regarding microscopic ECE.…”

Lymph Node Surgery - Stepwise Retirement for the Breast Surgeon?

“…If post-mastectomy radiotherapy including the regional nodes is indicated according to local protocols due to the positive SLN per se, ALND can be safely omitted, a lesson learned from EORTC AMAROS [12,31.] Finally, potential predictors of high nodal disease volume are sometimes used in clinical practice to indicate ALND; the most common are lymph node metastases detected by imaging before surgery and microscopic extranodal disease in the SLN [32,33,34] While the extent of extracapsular extension may influence the need for ALND [35], a positive imaging-guided axillary lymph node needle biopsy does not accurately predict the need for ALND [23.] BOOG 2013-07 from the Netherlands, SERC/IPC 2012-001 from France and the Alliance trial A011202 may eliminate most of the remaining indications for ALND, potentially leaving only confirmed palpable lymph node metastases as the last absolute indication for ALND in the near future.…”