Axillary lymph node dissection in triple-negative or HER2-positive breast cancer patients with clinical N2 achieving pathological complete response after neoadjuvant therapy: Is it necessary?

Outcomes and Trends in Axillary Management of Stage cN3b Breast Cancer Patients

BACKGROUND

There is limited data regarding sentinel lymph node biopsy (SLNB) after neoadjuvant chemotherapy (NAC) for cN3b patients, who present with both axillary and ipsilateral internal mammary node involvement. We examined trends in the use of SLNB in cN3b patients and survival by axillary procedure for those with nodal pathologic complete response (nPCR).

METHODS

Adult women with nonmetastatic cN3b invasive breast carcinoma between 2012 and 2021 were selected from the National Cancer Database. These patients were compared based on type of axillary surgery, specifically SLNB, SLNB with axillary lymph node dissection (ALND), and ALND alone. Kaplan-Meier analysis was used to compare overall survival.

RESULTS

A total of 4,236 patients were included. In 2012, 8.5% of these patients underwent SLNB alone and 18.3% underwent SLNB+ALND. In 2021, this increased to 35.1% for SLNB alone and 23.0% for SLNB with subsequent ALND (p < 0.0001). For patients who received NAC, the rate of nPCR was overall found to be 24.9%. Overall survival of patients receiving SLNB or SLNB+ALND with nPCR was not statistically significantly different from the ALND only group with nPCR (p = 0.22 and 0.57, respectively).

CONCLUSIONS

There has been increasing use of the SLNB procedure for patients with cN3b breast cancer over the past decade. In patients with nPCR, SLNB was not associated with reduced survival. For well-selected cN3b patients with an excellent clinical response to NAC, including nPCR, axillary de-escalation strategies, such as SLNB with omission of completion axillary dissection, may be considered.

The efficacy and oncological safety of minimally invasive axillary procedures in patients with node-positive breast cancer receiving neoadjuvant chemotherapy: A network meta-regression and trial sequential analysis

BACKGROUND

Neoadjuvant chemotherapy (NAC) can downstage axillary nodes in breast cancer, prompting debate over the optimal axillary management after NAC. While axillary dissection (ALND) provides detailed assessment of node status, minimally invasive methods such as sentinel lymph node biopsy (SLNB), marked lymph node biopsy (MLNB) and targeted axillary dissection (TAD) are showing promise. This meta-analysis aims to assess the efficacy and safety of these strategies.

METHODS

A systematic search of Medline, Embase and Cochrane Central was conducted and relevant RCTs were identified. Random-effects meta-analysis, meta-regression and trial sequential analysis (TSA) were conducted for diagnostic outcomes (identification rates [IFR], false negative rates [FNR] and negative predictive value [NPV]) and survival outcomes (overall survival [OS], disease-free survival [DFS]) to compare SLNB, MLNB and TAD with ALND.

RESULTS

Twenty-eight studies (SLNB, n = 3392; MLNB, n = 1130; TAD, n = 946) investigated diagnostic outcomes and nine studies investigated survival outcomes (n = 5647). The pooled IFR, FNR and NPV of TAD was 96.8 %, 4.7 % and 93.2 %, respectively, and all values were superior to SLNB (91.9 %, 13.7 % and 84.8 %; meta-regression, p < 0.001) (SLNB vs. MLNB concordance = 73 %). The FNR of SLNB decreased with the number of nodes removed (≥3 nodes, 8.1 %) but remained inferior to TAD (p = 0.001). The IFR of SLNB in the ycN0 group was statistically lower than all patients (ycN0/+), 85.8 % vs. 91.9 % (p < 0.001). Pooled hazard ratios for DFS in SLNB/TAD, SLNB and TAD were 0.90 (95%CI, 0.77-1.04; p = 0.45), 0.89 (95%CI, 0.74-1.08; p = 0.25) and 0.91 (95%CI, 0.64-1.29; p = 0.58) (TSA 2.08>threshold). Indirect comparison between TAD and SLNB demonstrated no significant difference in DFS (HR 0.98; 0.64-1.32; 95%CI, p = 0.95).

CONCLUSION

Targeted axillary dissection is the optimal minimally invasive axillary technique in terms of diagnostic accuracy. De-escalation of axillary surgery following NAC does not negatively impact DFS in patients with node-positive breast cancer.

Omission of Axillary Surgery After Neoadjuvant Therapy in Her2-Positive Breast Cancer: Who Are the Candidates?

Background: This study aimed to evaluate the lymph node (LN) response in Her2-positive breast cancer patients who received neoadjuvant therapy (NAT) and to discuss if axillary staging can be omitted in these patients. Methods: This is a retrospective cohort study including patients with Her2+ breast cancer at our center from March 2022 to September 2023. Results: The study included 139 patients in the final analysis; 69.1% of the patients had HR+/Her2+ disease while 30.9% had HR-/Her2+ disease. Most of the included patients (129 patients = 92.8%) had initially node-positive or suspicious disease. A total of 112 patients (80.6%) showed clinically negative axillary LNs (cN0) after NAT. All of them showed pathologically node-negative disease. When comparing the pathological node-positive vs. -negative groups, the following was found to be statistically significant: degree of Her2 positivity, number of anti-Her2 cycles, pre- and post-neoadjuvant LN status, and primary tumor radiological and pathological response. Also, all T1 tumors before NAT showed negative LNs after NAT, but it was statistically non-significant. Conclusions: Axillary staging may be omitted in Her2+ patients with cN0 after NAT, especially those with early tumors, strong Her2+ disease, cN0 before NAT, and those in whom the primary tumor achieved a complete clinical response.

Targeted axillary dissection using carbon marking for patients with node-positive breast cancer following neoadjuvant therapy (TADCOM): study protocol for a prospective, multicenter, randomized controlled trial

BACKGROUND

Neoadjuvant chemotherapy (NAC) for breast cancer enables pathological complete response (pCR) in patients initially diagnosed with axillary lymph node metastases, potentially obviating the need for axillary lymph node dissection (ALND). Current targeted axillary dissection (TAD) techniques, guided by traditional tissue markers placed prior to NAC, face challenges such as marker loss and high costs. Carbon nanoparticle suspension injection (CNSI) offers a stable and reliable alternative for marking, which could enhance the TAD procedure. This study aims to evaluate the feasibility and accuracy of different TAD strategies using CNSIs and to explore their clinical utility in locally advanced breast cancer.

METHODS

This prospective, multicenter, randomized controlled trial will enroll 126 biopsy-proven breast cancer patients with suspicious axillary lymph node metastases (cN1-2a) who achieve ycN0 status following NAC. Participants will be randomized in a 1:1:1 ratio to undergo TAD guided by: [1] conventional tissue clips (CG-TAD); [2] CNSI lymph node marking (CN-LNM); or [3] peritumoral CNSI mapping (PCN-MAP). Primary endpoints include retrieval rate of marked lymph nodes, number of sentinel and marked lymph nodes, concordance rates, and complication rates. Secondary endpoints encompass regional and distant recurrence rates, survival outcomes, surgical duration, postoperative complications, quality of life scores, and margin status in breast-conserving surgery. Statistical analyses will adhere strictly to the CONSORT guidelines.

DISCUSSION

This study aims to evaluate the feasibility and accuracy of CNSI for targeted axillary dissection in breast cancer patients following neoadjuvant chemotherapy and to explore its clinical significance in reducing surgical complications and costs, as well as improving surgical precision.

TRIAL REGISTRATION

Clinicaltrials.gov, NCT04744506, Registered 27 December 2020, Updated 24 September 2024. Protocol Version Ver 1.2, 17/9/2024.

Axillary de-escalation after neoadjuvant chemotherapy for advanced lymph node involvement in breast cancer

INTRODUCTION

Sentinel lymph node biopsy reduces morbidity in patients with clinically node-positive breast cancer who achieve axillary pathologic complete response following neoadjuvant therapy (NACT). De-escalation trials primarily addressed cN1 disease, with underrepresentation of cN2 disease. This study evaluates the role of de-escalation in patients with cN2 breast cancer.

METHODS

A retrospective analysis of the National Cancer Database (2013-2020) included women over 18 with T1-2 invasive breast cancer and clinical N2 disease who received NACT followed by ALND or SLNB then ALND. The primary outcome was pathologic nodal status post-NACT.

RESULTS

Of 5852 cN2 patients treated, 18.15 ​% achieved ypN0, 0.97 ​% had isolated tumor cells, 19.14 ​% were ypN1, 49.64 ​% were ypN2, and 12.20 ​% were ypN3 following NACT. Achieving ypN0 was associated with pCR in the breast, HER2-positive and triple-negative receptor status, cT2 tumors, and younger age.

CONCLUSION

Despite some patients with cN2 disease achieving ypN0, most exhibited residual axillary disease post-NACT. These findings indicate that axillary de-escalation may not be feasible for most patients with cN2 disease, underscoring the importance of meticulous patient selection and assessment.

Evaluating Radar Reflector Localisation in Targeted Axillary Dissection in Patients Undergoing Neoadjuvant Systemic Therapy for Node-Positive Early Breast Cancer: A Systematic Review and Pooled Analysis

SAVI SCOUT® or radar reflector localisation (RRL) has proven accurate in localising non-palpable breast and axillary lesions, with minimal interference with MRI. Targeted axillary dissection (TAD), combining marked lymph node biopsy (MLNB) and sentinel lymph node biopsy (SLNB), is becoming a standard post-neoadjuvant systemic therapy (NST) for node-positive early breast cancer. Compared to SLNB alone, TAD reduces the false negative rate (FNR) to below 6%, enabling safer axillary surgery de-escalation. This systematic review evaluates RRL's performance during TAD, assessing localisation and retrieval rates, the concordance between MLNB and SLNB, and the pathological complete response (pCR) in clinically node-positive patients post-NST. Four studies (252 TAD procedures) met the inclusion criteria, with a 99.6% (95% confidence [CI]: 98.9-100) successful localisation rate, 100% retrieval rate, and 81% (95% CI: 76-86) concordance rate between SLNB and MLNB. The average duration from RRL deployment to surgery was 52 days (range:1-202). pCR was observed in 42% (95% CI: 36-48) of cases, with no significant migration or complications reported. Omitting MLNB or SLNB would have under-staged the axilla in 9.7% or 3.4% (p = 0.03) of cases, respectively, underscoring the importance of incorporating MLNB in axillary staging post-NST in initially node-positive patients in line with the updated National Comprehensive Cancer Network (NCCN) guidelines. These findings underscore the excellent efficacy of RRL in TAD for NST-treated patients with positive nodes, aiding in accurate axillary pCR identification and the safe omission of axillary dissection in strong responders.