- The ACOSOG Z1071 trial:
- Was designed to determine the false negative rate (FNR) of sentinel lymph node biopsy (SLNB) after neoadjuvant chemotherapy (NAC) in women initially presenting with cN1 disease
- The trial enrolled women from 136 institutions who had:
- Clinical T0 through T4, N1 through N2, M0 breast cancer who received neoadjuvant chemotherapy
- Patients enrolled had pre-chemotherapy axillary nodal disease confirmed by fine-needle aspiration or core needle biopsy
- Following NAC:
- Patients underwent both SLNB, followed by a back-up axillary lymph node dissection
- SLNB with dual tracer using both blue dye (isosulfan blue or methylene blue) and a radiolabeled colloid mapping agent was encouraged
- Rates of detection of at least one SLN were 92.9% in patients with cN1 disease and 89.5% in patients with cN2 disease
- Overall, the FNR of SLNB after NAC was 12.6%
- Bivariable analyses found that the likelihood of a false-negative SLN finding was significantly decreased when:
- The mapping was performed with the combination of blue dye and radiolabeled colloid:
- P=.05; FNR, 10.8% combination vs 20.3% single agent
- By removal of at least 3 SLNs:
- P=.007; FNR, 9.1% for ≥ 3 SLNs vs 21.1% for two
- The mapping was performed with the combination of blue dye and radiolabeled colloid:
- A clip was placed at initial node biopsy prior to NAC in 203 patients:
- In the 170 (83.7%) patients with cN1 disease and at least two SLNs resected, clip location was confirmed in 141 cases
- In 107 (75.9%) patients where the clipped node was within the SLN specimen, the FNR was 6.8% (confidence interval [CI]: 1.9%-16.5%)
- If the clipped node was found in the ALND specimen, the FNR was 19.0% (CI: 5.4%-41.9%)
- In cases where a clip was not placed (n = 355) and in those where the clipped node location was not confirmed at surgery (n = 29):
- The FNR was 13.4% and 14.3%, respectively
- While the FNR overall exceeded the 10% threshold considered to be clinically acceptable:
- The authors concluded that with modifications to the SLN technique (i.e., dual tracer mapping and retrieval of at least 3 negative SLNs), to the FNR was < 10% and supported the use of SLN surgery as an alternative to axillary lymph node dissection in this patient population
- Subsequently, Caudle et al have reported a separate registry of 191 patients and showed that removing the clipped positive node in addition to SLN:
- Had an FNR as low as 2.0%
- References
- Boughey JC, Suman VJ, Mittendorf EA, Ahrendt GM, Wilke LG, Taback B, et al.; Alliance for Clinical Trials in Oncology. Sentinel lymph node surgery after neoadjuvant chemotherapy in patients with node-positive breast cancer: the ACOSOG Z1071 (Alliance) clinical trial. JAMA. 2013;310(14):1455-1461.
- Boughey JC, Ballman KV, Le-Petross HT, McCall LM, Mittendorf EA, Ahrendt GM, et al. Identification and resection of clipped node decreases the false-negative rate of sentinel lymph node surgery in patients presenting with node-positive breast cancer (T0-T4, N1-N2) who receive neoadjuvant chemotherapy: results from ACOSOG Z1071 (Alliance). Ann Surg. 2016;263(4):802-807.
- Caudle AS, Yang WT, Krishnamurthy S, Mittendorf EA, Black DM, Gilcrease MZ, et al. Improved axillary evaluation following neoadjuvant therapy for patients with node-positive breast cancer using selective evaluation of clipped nodes: implementation of targeted axillary dissection. J Clin Oncol. 2016;34(10):1072-1078.
American College of Surgeons Oncology Group (ACOSOG) Z1071 Trial
Rodrigo Arrangoiz MS, MD, FACS, FSSO 