Sentinel Lymph Node Biopsy in Breast Cancer Patients With Pathological Complete Response in the Axillary Lymph Node After Neoadjuvant Chemotherapy

Different strategies in de-escalation of axillary surgery in node-positive breast cancer following neoadjuvant treatment: a systematic review and meta-analysis of long-term outcomes

PURPOSE

Different surgical options existed in the management of axilla among breast cancer patients who were initially node-positive and were converted node-negative after neoadjuvant systemic treatment (NST). De-escalation of axillary surgery was feasible, but previous studies focused on the false-negative rate (FNR) of respective procedures. The aim of this study is to evaluate the oncological outcomes of sentinel lymph-node biopsy (SLNB), MARI procedure, and targeted axillary dissection (TAD).

PATIENTS AND METHODS

PubMed, Embase, and the Cochrane library literature databases were searched systematically. Studies were eligible if they addressed the axillary recurrence rate of patients with nodal pathological complete response (pCR) and omission of axillary lymph-node dissection (ALND) after NST. Pooled analysis was performed using inverse variance methods for logit transformed proportions.

RESULTS

Eleven retrospective studies and three prospective studies involving 4268 patients with node-positive breast cancers were included. A total of 1650 patients achieved nodal pCR and avoided ALND, 1382 patients with SLNB only and 268 patients with MARI/TAD. The pooled estimate of axillary recurrence was 2.1% (95%CI 1.4-3.2%) for patients with negative SLNB and 1.5% (95% CI 0.5-4.1%) for patients with negative MARI/TAD. There was no significant benefit of ALND over SLNB in patients with nodal pCR after NST. Pooled estimates of 5-year DFS, DDFS, and OS of SLNB alone were 0.87 (95% CI 0.83-0.90], 0.90 (95% CI 0.88-0.92), and 0.92 (95% CI 0.88-0.94), respectively.

CONCLUSION

Breast cancer patients who are converted node-negative after NST have extremely low nodal recurrence rate, irrespective of the choice of axillary surgery. Omission of ALND is oncologically safe in patients who have nodal pCR after NST.

Feasibility of de-escalating axillary surgery in patients with clinical N2-3, pathological N0 breast cancer after neoadjuvant chemotherapy

Axillary lymph node dissection (ALND) omission improves quality of life but is only considered under certain conditions. We investigated expanding these conditions in patients receiving neoadjuvant chemotherapy (NAC) for clinical N2-3, pathological N0 breast cancer. We retrospectively reviewed data of 1346 patients with clinical N2-3, M0, who underwent surgical resection (sentinel lymph node biopsy [SLNB] only, or level I-II ALND with/without SLNB) following NAC from January 2008 to December 2021. Univariate and multivariate analyses of overall (OS), disease-free (DFS), regional recurrence-free (RFS), and axillary recurrence-free survival (ARFS) were performed before and after propensity score matching (PSM) to control for confounding factors. Of the total patients, 521 (37.5%) achieved an axillary pathological complete response (ypN0). Of these, 293 (56.2%) underwent SLNB only. The median OS was 52.7 months. After PSM, SLNB-only and ALND groups showed no significant differences in ARFS (long-rank p = 0.765), RFS (long-rank p = 0.764), DFS (long-rank p = 0.186), and OS (long-rank p = 0.760). The 5-year ARFS (97.3 vs. 96.7%) and OS (97.7 vs. 97.3%) of both groups did not differ significantly. ALND omission after NAC in clinical N2-3, pathological N0 patients was not inferior to ALND,. Clinical N2-3 patients achieving ypN0 following NAC may be safely treated with SLNB alone.

Omission of axillary lymph node dissection in patients with breast cancer with axillary pathological complete response confirmed by stained region lymph node biopsy after neoadjuvant systemic therapy (SrLNB study): study protocol for a single-arm, single-centre, phase-II trial

INTRODUCTION

Given that axillary lymph node dissection (ALND) may not contribute to local control or survival and could lead to increased arm morbidity, axillary de-escalation procedures have replaced ALND in patients achieving axillary pathologic complete response (apCR) after neoadjuvant systemic therapy (NST). However, the application of targeted lymph node biopsy, one of the de-escalation procedures, remains limited due to a lack of long-term follow-up studies.

METHODS AND ANALYSIS

This prospective, single-arm, open-label, non-inferiority, single-centre phase II trial targets breast cancer patients initially diagnosed with axillary metastasis who achieved apCR after NST. The study aims to validate the oncological safety of stained region lymph node biopsy (SrLNB) procedure. SrLNB is a novel de-escalation axillary surgery, which was developed and tested in our preliminary study. The primary endpoint of this trial is the 3-year invasive disease-free survival (iDFS). Secondary endpoints include local-regional recurrence, incidence of breast cancer-related lymphoedema and patient-reported outcomes. The 3-year iDFS in patients undergoing ALND is expected to be approximately 90%, with a non-inferiority margin of 10%, a significance level of 0.05, power of 0.8 and a loss-to-follow-up rate of 10%. The planned enrolment is 92 patients. The trial was initiated on 11 September 2023, with the first patient enrolled on 25 September 2023, and is scheduled to end in 2026.

ETHICS AND DISSEMINATION

The trial protocol received approval from the Human Research Ethics Committee of The First Affiliated Hospital with Nanjing Medical University in May 2023 (No. 2023-SR-169). All participants will provide informed consent. The study results will be disseminated through international peer-reviewed scientific journals, presentations at international scientific conferences and public lectures.

TRIAL REGISTRATION NUMBER

NCT05939830.

Axillary lymph node management strategies in cN + breast cancer patients after neoadjuvant chemotherapy

With the widespread use of neoadjuvant chemotherapy (NAC), the optimal management strategy for axillary lymph nodes following chemotherapy has become a hot topic of discussion. For patients with clinically positive axillary lymph nodes (cN +) (defined as axillary lymph nodes confirmed positive by pathology before NAC), axillary lymph node dissection (ALND) remains the current standard treatment. However, there is still no consensus on whether sentinel lymph node biopsy (SLNB) and other local axillary treatments following NAC can safely replace ALND to reduce injury and complications. This article provides a narrative review of strategies for managing axillary lymph nodes in this patient population.

Use of ultrasound and MRI to stage the axilla for breast cancer before and after neoadjuvant chemotherapy prior to targeted sentinel lymphadenectomy

PURPOSE

Prior data from this Center demonstrated that for patients who had biopsy-proven axillary metastases, were ycN0 after neoadjuvant chemotherapy (NAC), and had a wire-directed (targeted) sentinel lymphadenectomy (WD-SLND), 60% were node negative. The hypothesis of this study was that results of axillary imaging either before or after NAC would be predictive of final pathologic status after WD-SLND.

METHODS

For patients treated with NAC between 2015 and 2023, ultrasound and MRI images of the axilla were retrospectively reviewed by radiologists specializing in breast imaging, who were blinded to the surgical and pathology results.

RESULTS

Of 113 patients who fit the clinical criteria, 66 (58%) were ypN0 at WD-SLND and 34 (30%) had a pathologic complete response to NAC. There was no correlation between the number of abnormal lymph nodes on pre-NAC ultrasound or MRI imaging and the final pathologic status of the lymph nodes. The positive predictive value (PPV) of abnormal post-NAC axillary imaging was 48% for ultrasound and 53% for MRI. The negative predictive value (NPV) for normal post-NAC axillary imaging was 67% for ultrasound and 68% for MRI.

CONCLUSION

The results of axillary imaging were not adequate to identify lymph nodes after NAC that were persistently pathologically node positive or those which had become pathologically node negative.

De-escalation of Axillary Surgery After Neoadjuvant Therapy

Surgical de-escalation of the axilla has evolved over the past 28 years since the emergence of sentinel lymph node surgery. Well-documented complications of the once standard of care axillary lymph node dissection (ALND), including lymphedema, led physician scientists towards a progressive push to study and incorporate less invasive techniques in the axilla. Many trials have justified oncologic safety of axillary de-escalation in patients who are spared neoadjuvant treatment. The applicability in the neoadjuvant setting, however, is less clear and axillary surgical approaches in this patient population have evolved at a slower pace. This review aims to analyze current data in axillary management for patients undergoing neoadjuvant treatment and to discuss current surgical approaches based on nodal pathologic response.

The Role of Sentinel Lymph Node Biopsy in Breast Cancer Patients Who Become Clinically Node-Negative Following Neo-Adjuvant Chemotherapy: A Literature Review

BACKGROUND

In clinically node-positive (cN+) breast cancer (BC) patients who become clinically node-negative (cN0) following neoadjuvant chemotherapy (NACT), sentinel lymph node biopsy (SLNB) after lymphatic mapping with lymphoscintigraphy is not widely accepted; therefore, it has become a topic of international debate.

OBJECTIVE

Our literature review aims to evaluate the current use of this surgical practice in a clinical setting and focuses on several studies published in the last six years which have contributed to the assessment of the feasibility and accuracy of this practice, highlighting its importance and oncological safety. We have considered the advantages and disadvantages of this technique compared to other suggested methods and strategies. We also evaluated the role of local irradiation therapy after SLNB and state-of-the-art SLN mapping in patients subjected to NACT.

METHODS

A comprehensive search of PubMed and Cochrane was conducted. All studies published in English from 2018 to August 2023 were evaluated.

RESULTS

Breast units are moving towards a de-escalation of axillary surgery, even in the NACT setting. The effects of these procedures on local irradiation are not very clear. Several studies have evaluated the oncological outcome of SLNB procedures. However, none of the alternative techniques proposed to lower the false negative rate (FNR) of SLNB are significant in terms of prognosis.

CONCLUSIONS

Based on these results, we can state that lymphatic mapping with SLNB in cN+ BC patients who become clinically node-negative (ycN0) following NACT is a safe procedure, with a good prognosis and low axillary failure rates.

Surgical Management of the Axilla for Breast Cancer

This review discusses the contemporary surgical management of the axilla in patients with breast cancer. Surgical paradigms are highlighted by clinical nodal status at presentation and treatment approach, including upfront surgery and neoadjuvant systemic therapy settings. This review focuses on the increasing opportunities for de-escalating the extent of axillary surgery in the era of sentinel lymph node biopsy, while also reviewing the remaining indications for axillary clearance with axillary lymph node dissection.