Axillary lymph node dissection versus radiotherapy in breast cancer with positive sentinel nodes after neoadjuvant therapy (ADARNAT trial)

Effect of post-mastectomy radiation therapy on survival in breast cancer with lymph nodes micrometastases: a meta-analysis and systematic review

Background

Axillary management of patients with early-stage breast cancer (ESBC) has evolved, especially with the implementation of precision radiotherapy techniques that have resulted in a significant reduction in treatment-related toxicities, but it is unclear whether post-mastectomy radiotherapy (PMRT) improves survival outcomes in breast cancer with lymph nodes micrometastases (BCLNMM, that is T0, T1 ~2NmiM0). Our study is to systematically evaluate the effect of PMRT on survival in breast cancer with lymph nodes micrometastases.

Methods

A literature search was performed for randomized controlled trials (RCTs) or retrospective studies related to PMRT versus non-post-mastectomy radiotherapy (non-PMRT) in the adjuvant treatment of ESBC in PubMed, Cochrane Library, Embase, CNKI and other databases. R package meta software was used to perform meta-analyses with hazard ratio (HR). Newcastle Ottawa scale was selected for quality assessment. The review was prospectively registered on PROSPERO (CRD42024562444).

Results

10 relevant studies were screened, all of which were retrospective studies. The difference in overall survival (OS) was not statistically significant (HR = 0.92, 95%CI: 0.81 ~ 1.04; Z = 1.35, P = 0.177). The difference in breast cancer-specific survival (BCSS) between the PMRT group and the non-PMRT group was not statistically significant HR = 1.18, 95%CI: 0.94 ~ 1.48; Z = 1.41, P =0.160). The difference in disease-free survival (DFS) was statistically significant (HR = 0.47, 95%CI: 0.23 ~ 1.00; Z = 1.96, P =0.049). The difference in local recurrence free survival (LRRFS) was also not statistically significant (HR = 0.50, 95%CI: 0.11 ~ 2.26, P = 0.190). The difference in distant-metastasis free survival (DMFS) was not statistically significant (HR = 0.54, 95%CI: 0.22 ~ 1.35, P = 0.356).

Conclusions

Despite the tendency of PMRT in BCLNMM to improve DFS, OS, BCSS, LRRFS, and DMFS showed no benefit, therefore, PMRT should be used with caution in BCLNMM.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42024562444.

Axillary Reverse Mapping Using Indocyanine Green in Breast Cancer: Standardization of the Technique

PURPOSE

To validate the Axillary Reverse Mapping (ARM) technique with indocyanine green (ICG), focusing on the detection rate and the procedure's feasibility. The predictive factors for metastatic involvement of ARM nodes are also analyzed to define the target population for ARM indication.

METHODS

This prospective, observational, non-randomized study of patients with breast cancer included patients with an indication for axillary lymph node dissection (ALND) performed between June 2021 and June 2023. Participants were divided into two cohorts based on pattern of ICG migration: standard technique (all ARM nodes) and targeted technique (in contact with axillary vein). The feasibility of identifying and preserving ARM nodes during ALND was assessed. Multivariate logistic regression was used to analyze predictive factors (eg, tumor size, molecular surrogate subtype, multifocality, and neoadjuvant therapy) for metastatic ARM nodes.

RESULTS

Of the 41 patients in whom we performed the ARM technique, ARM nodes were identified and preserved after ALND in 36 patients (87.8%). Of these, 17 (89.5%) underwent the standard technique and 19 (86.4%) underwent the targeted technique. ARM metastases were identified in 12 patients: 9 (47.1%) with the standard technique and 3 (15.7%) with the targeted technique (P = .026). The ARM technique was the only risk factor for ARM involvement (odds ratio, 15.9; 95% confidence interval, 1.1-218.6).

CONCLUSIONS

ICG facilitates the successful completion of ARM in almost 90% of patients undergoing ALND. In addition, by selecting the ARM nodes closest to the axillary vein, the number of cross metastases can be significantly reduced.

Omitting axillary lymph node dissection in breast cancer patients with extensive nodal disease and excellent response to primary systemic therapy using the MARI protocol

PURPOSE

Axillary lymph node staging techniques after primary systemic therapy (PST) show low false negative rates, stimulating the omission of axillary lymph node dissection (ALND). Breast cancer patients with extensive nodal disease are underreported in studies on response-guided axillary treatment. In this study, we present the oncologic outcome of breast cancer patients with ≥4 involved axillary lymph nodes treated according to the MARI-protocol.

METHODS

This prospective single arm registration study included breast cancer patients with extensive nodal disease defined as ≥4 involved axillary lymph nodes on FDG-PET/CT pre-PST between July 2014 and December 2021. After PST, the marked (MARI) lymph node was excised. Patients with a pathologic complete response (pCR) of the MARI node (ypN0) received locoregional radiation treatment (RT). In patients with residual disease of the MARI node (ypN+), ALND was performed followed by RT. Primary endpoint was axillary recurrence rate. Secondary endpoints were invasive disease-free survival (DFS) and overall survival (OS).

RESULTS

In total, 218 patients were registered of which 39 % of patients also had extra-axillary nodal disease. Median (IQR) age was 50 (42-57) years. After PST 47 % of patients (103/218) had ypN0, whereas 53 % of patients (115/218) had ypN+. After a median follow up of 44 (26-62) months, axillary recurrence rate was 2.9 % (n = 3) in the ypN0 group and 3.5 % (n = 4) in the ypN + group. Five-year invasive DFS and OS were respectively 89 % (95 % CI 83 %-96 %) and 95 % (95 % CI 91 %-99 %) in ypN0 patients.

CONCLUSION

Omission of ALND after PST in breast cancer patients with extensive nodal involvement who achieve pCR of the MARI node is associated with excellent five-year oncologic outcome.

Mapping the current landscape of locoregional therapy de-escalation trials in early breast cancer: a systematic review

A systematic review undertaken to map the current landscape of locoregional de-escalation trials to inform future research. Online databases and trial registries were searched to identify ongoing, recently completed or published studies de-escalating surgery or radiotherapy in patients with early breast cancer. 97 trials evaluated de-escalation of surgery or radiotherapy in up to 94,866 participants. Surgery studies more commonly evaluated treatment omission/reduction after neoadjuvant systemic therapy (NST) and de-escalation of nodal treatment. Radiotherapy studies were more frequently biomarker stratified. Patients were rarely involved in study design. Research questions focused on response-adjusted treatment after NST and omission/reduction of locoregional therapy in patients with low- or intermediate-risk disease. Significant duplication was identified with multiple studies addressing similar questions. This systematic review demonstrates that the current de-escalation portfolio is inefficient, lacks patient focus and needs improvement. An internationally collaborative approach using innovative study designs and patient partnership will be essential to address this.

De-escalation of axillary treatment in early breast cancer-a narrative review of current trials

Background and Objective

In the era of de-escalation and minimally invasive locoregional treatments across many fields of surgical oncology, the treatment of the axilla in breast cancer has garnered significant interest. While the knowledge of axillary lymph node involvement is crucial for multidisciplinary management, the surgical approach to the axillary basin can have potential disadvantages that may impact the quality of life. The objective of this narrative review is to examine studies about de-escalation of axillary treatment in various clinical scenarios, namely the settings of upfront surgery and neoadjuvant systemic treatments. Moreover, trials investigating omission of axillary surgery were examined.

Methods

As of July 2024, a comprehensive literature search, compilation, and analysis were conducted across PubMed, Scopus, Web of Sciences, and ClinicalTrials.gov.

Key Content and Findings

In patients with clinically node-negative lymph nodes and up to two positive sentinel nodes, avoiding axillary lymph node dissection is a safe option. As for patients receiving neoadjuvant systemic treatment, axillary lymph node dissection is unnecessary if no residual tumor burden remained in the lymph nodes after surgery. Additionally, studies have shown that axillary radiotherapy can be as effective as axillary dissection in certain cases. The avoidance of any axillary surgery might be proposed to highly select sub-groups patients with small tumors and negative on clinical and ultrasound evaluation lymph nodes.

Conclusions

To date, determining the appropriate axillary treatment remains a complex decision that must be made by multidisciplinary teams with expertise in personalized breast cancer treatment.

Predicting axillary lymph node metastasis in breast cancer using a multimodal radiomics and deep learning model

Objective

To explore the value of combined radiomics and deep learning models using different machine learning algorithms based on mammography (MG) and magnetic resonance imaging (MRI) for predicting axillary lymph node metastasis (ALNM) in breast cancer (BC). The objective is to provide guidance for developing scientifically individualized treatment plans, assessing prognosis, and planning preoperative interventions.

Methods

A retrospective analysis was conducted on clinical and imaging data from 270 patients with BC confirmed by surgical pathology at the Third Hospital of Shanxi Medical University between November 2022 and April 2024. Multiple sequence images from MG and MRI were selected, and regions of interest in the lesions were delineated. Radiomics and deep learning (3D-Resnet18) features were extracted and fused. The samples were randomly divided into training and test sets in a 7:3 ratio. Dimensionality reduction and feature selection were performed using the least absolute shrinkage and selection operator (LASSO) regression model, and other methods. Various machine learning algorithms were used to construct radiomics, deep learning, and combined models. These models were visualized and evaluated for performance using receiver operating characteristic curves, area under the curve (AUC), calibration curves, and decision curves.

Results

The highest AUCs in the test set were achieved using radiomics-logistic regression (AUC = 0.759), deep learning-multilayer perceptron (MLP) (AUC = 0.712), and combined-MLP models (AUC = 0.846). The MLP model demonstrated strong classification performance, with the combined model (AUC = 0.846) outperforming both the radiomics (AUC = 0.756) and deep learning (AUC = 0.712) models.

Conclusion

The multimodal radiomics and deep learning models developed in this study, incorporating various machine learning algorithms, offer significant value for the preoperative prediction of ALNM in BC.

Breast and axillary marking in the neoadjuvant setting: survey results from experts of the Brazilian society of mastology

Introduction/objectives

The precise location of the tumor site is essential for the success of surgical treatment. Neoadjuvant chemotherapy (NAC) is a challenge for preoperative tumor and node localization. Thus, the knowledge and attitudes of the affiliated members of the Brazilian Society of Mastology (SBM) regarding breast and axilla marking were evaluated and a consensus regarding management and treatment was reached.

Methods

This was an online survey conducted between June and December 2022. All 1,742 active mastologists affiliated to the SBM were invited anonymously. The online form contained 28 objective questions, of which 22 were formulated on a Likert scale. These questions addressed relevant aspects related to breast and axilla marking in the neoadjuvant setting. Responses that reached 70% agreement were considered consensual. Statistical analysis was performed using the SPSS program version 26.0. Post hoc analysis was performed when appropriate and the significance level was set at p < 0.05. Polychoric regression analyses were conducted using `VGAM` package.

Results

In total, 468 mastologists answered the questionnaire (26.8%), with a predominance of professionals aged between 40-49 years (32.1%). Most professionals were board-certified (84,8%). The indication of tumor marking in the breast prior to NAC was consensual (96.4%) and the metal clip was the preferred method (69.7%). There was no consensus regarding the indication of pre-NAC histologically positive lymph node marking (49.8% disagree and 42.8% agree). However, there was consensus that the clinical and imaging evaluation was insufficient for staging the axilla as N1 (71.6%). The contraindication of breast and node marking in T4b tumors (71.2%) was consensual. There was consensus on the indication of sentinel lymph node biopsy (SLNB) for initially cN1 (92.3%) or cN2 (72.7%) tumors that became cN0 after NAC, with 67.5% opting for dual staining with technetium and patent blue. When <3 lymph nodes were retrieved 41.0% of mastologists performed axillary lymphadenectomy. Among the 28 questions, consensus was reached on only 11 (39.3%).

Conclusion

The indication of pre-NAC breast marking is consensual among Brazilian mastologists, although axillary nodal marking is not. There is a great divergence of attitudes among Brazilian surgeons in relation to the many issues related to pre-NAC breast and axilla marking.

Surgery paradigm for locally advanced breast cancer following neoadjuvant systemic therapy

Locally advanced breast cancer (LABC) remains a significant clinical challenge, particularly in developing countries. While neoadjuvant systemic therapy (NST) has improved the pathological complete response (pCR) rates, particularly in HER2-positive and triple-negative breast cancer patients, surgical management post-NST continues to evolve. The feasibility of omitting surgery and the increasing consideration of breast-conserving surgery, immediate reconstruction in LABC patients are important areas of exploration. Accurate assessment of tumor response to NST through advanced imaging and minimally invasive biopsies remains pivotal, though challenges persist in reliably predicting pCR. Additionally, axillary lymph node management continues to evolve, with emerging strategies aiming to minimize the extent of surgery in patients who achieve nodal downstaging post-NST. Minimizing axillary lymph node dissection in favor of less invasive approaches is gaining attention, though further evidence is needed to establish its oncological safety. The potential for personalized treatment approaches, reducing surgical morbidity, and improving quality of life are key goals in managing LABC, while maintaining the priority of achieving favorable long-term outcomes.

Retrieval of the Clipped Axillary Lymph Node and Its Impact on Treatment Decisions

We examined clinically node-positive (cN+) breast cancer patients undergoing neoadjuvant chemotherapy and clipped lymph node (CLN) localization to determine the rate of CLN = non-sentinel lymph node (SLN), the factors associated with cN+ to pN0 conversion, and the treatment impact. We conducted a single institution review of cN+ patients receiving NAC from 2016 to 2022 with preoperative CLN localization (N = 81). Demographics, hormone receptor (HR) and HER2 status, time to surgery, staging, chemotherapy regimen, localization method, pathology, and adjuvant therapy were analyzed. Pathologic complete response (pCR) of the CLN was observed in 41 patients (50.6%): 18.8% HR+/HER2-, 75% HR+/HER2+, 75% HR-/HER2+, and 62.5% triple-negative breast cancer (p-value = 0.006). CLN = SLN in 68 (84%) patients, while CLN = non-SLN in 13 (16%). In 14 (17.3%) patients, the final treatment was altered based on +CLN status: 11 patients underwent axillary lymph node dissection (ALND), and 3 had systemic treatment changes. pCR rates varied, with the highest conversion rates observed in HER2+ disease and the lowest in HR+/HER2- disease. In 2 (2.5%) patients, adjuvant therapy changes were made based on a non-sentinel CLN, while in 97.5% of patients, a SLN biopsy alone represented the status of the axilla. This demonstrates that a +CLN often alters final plans and that, despite also being a SLN in most cases, a subset of patients will be undertreated by SLN biopsy alone.

Sentinel lymph node biopsy before and after neoadjuvant chemotherapy in cN0 breast cancer patients: impact on axillary morbidity and survival-a propensity score cohort study

PURPOSE

In patients with clinically lymph node-negative (cN0) breast cancer, performing sentinel lymph node biopsy (SLNB) after neoadjuvant chemotherapy (NACT) has been preferentially embraced in comparison to before NACT. However, survival outcomes associated with both strategies remain understudied. We aimed to compare the axillary lymphadenectomy (ALND) rate, disease-free survival (DFS), and overall survival (OS), between two strategies.

METHODS

We included 310 patients in a retrospective observational study. SNLB was performed before NACT from December 2006 to April 2014 (107 cases) and after NACT from May 2014 to May 2020 (203 patients). An inverse probability of treatment weighting (IPTW) method was applied to homogenize both groups. Hazard ratios (HR) and odd ratios (OR) are reported with 95% confidence intervals (95%CI).

RESULTS

The lymphadenectomy rate was 29.9% before NACT and 7.4% after NACT (p < 0.001), with an OR of 5.35 95%CI (2.7-10.4); p = .002. After 4 years of follow-up, SLNB after NACT was associated with lower risk for DFS, HR 0.42 95%CI (0.17-1.06); p = 0.066 and better OS, HR 0.21 CI 95% (0.07-0.67); p = 0.009 than SLNB before NACT. After multivariate analysis, independent adverse prognostic factors for OS included SLNB before NACT, HR 3.095 95%CI (2.323-4.123), clinical nonresponse to NACT, HR 1.702 95% CI (1.012-2.861), and small tumors (cT1) with high proliferation index, HR 1.889 95% (1.195-2.985).

CONCLUSION

Performing SLNB before NACT results in more ALND and has no benefit for patient survival. These findings support discontinuing the practice of SLNB before NACT in patients with cN0 breast cancer.

Axillary Surgery for Breast Cancer in 2024

Axillary surgery for patients with breast cancer (BC) in 2024 is becoming increasingly specific, moving away from the previous 'one size fits all' radical approach. The goal is to spare morbidity whilst maintaining oncologic safety. In the upfront surgery setting, a first landmark randomized controlled trial (RCT) on the omission of any surgical axillary staging in patients with unremarkable clinical examination and axillary ultrasound showed non-inferiority to sentinel lymph node (SLN) biopsy (SLNB). The study population consisted of 87.8% postmenopausal patients with estrogen receptor-positive, human epidermal growth factor receptor 2-negative BC. Patients with clinically node-negative breast cancer and up to two positive SLNs can safely be spared axillary dissection (ALND) even in the context of mastectomy or extranodal extension. In patients enrolled in the TAXIS trial, adjuvant systemic treatment was shown to be similar with or without ALND despite the loss of staging information. After neoadjuvant chemotherapy (NACT), targeted lymph node removal with or without SLNB showed a lower false-negative rate to determine nodal pathological complete response (pCR) compared to SLNB alone. However, oncologic outcomes do not appear to differ in patients with nodal pCR determined by either one of the two concepts, according to a recently published global, retrospective, real-world study. Real-world studies generally have a lower level of evidence than RCTs, but they are feasible quickly and with a large sample size. Another global real-world study provides evidence that even patients with residual isolated tumor cells can be safely spared from ALND. In general, few indications for ALND remain. Three randomized controlled trials are ongoing for patients with clinically node-positive BC in the upfront surgery setting and residual disease after NACT. Pending the results of these trials, ALND remains indicated in these patients.

[Can we avoid axillary lymph node dissection in patients with node positive invasive breast carcinoma?]

OBJECTIVES

The indications and modalities of breast and axillary surgery are undergoing profound change, with the aim of personalizing surgical management while avoiding over-treatment. To update best practices for axillary surgery, four questions were selected by the Senology Commission of the Collège National des Gynécologues et Obstétriciens Français (CNGOF), focusing on, firstly, the definition and evaluation of targeted axillary dissection (TAD) techniques; secondly, the possibility of surgical de-escalation in case of initial lymph node involvement while performing initial surgery; thirdly, in case of surgery following neo-adjuvant systemic therapy (NAST), and fourthly, contra-indications to de-escalation of axillary surgery to allow access to particular adjuvant systemic therapies.

METHODS

The Senology Commission based its responses primarily on an analysis of the international literature, clinical practice recommendations and national and international guidelines.

RESULTS

Firstly, TAD is a technique that combines excision of clipped metastatic axillary node(s) and the axillary sentinel lymph nodes (ASLNs). The detection rate and sensitivity are increased but it still needs to be standardized and practices better evaluated. Secondly, TAD represents an alternative to axillary clearance in cases of metastatic involvement of a single node that can be resected. Thirdly, neither TAD nor ASLN alone is recommended in France after NAST outside of clinical trials, although it is used in several countries in cases of complete pathological response in the lymph nodes, and when at least three lymph nodes have been removed. Fourthly, as some adjuvant targeted therapies are indicated in cases of lymph node invasion of more than three lymph nodes, the place of TAD in this context remains to be defined.

CONCLUSION

Axillary surgical de-escalation can limit the morbidity of axillary clearance. Having proved that TAD does not reduce patient survival, it will most probably replace axillary clearance in well-defined indications. This will require prior standardization of the method and its indications and contra-indications, particularly to enable the use of new targeted therapies.