Debating the Optimal Approach to Nodal Management After Pathologic Complete Response to Neoadjuvant Chemotherapy in Patients With Breast Cancer

Predictors of axillary node response in node-positive patients undergoing neoadjuvant chemotherapy for breast cancer

Background:

The ability to accurately predict which patients will achieve a pathologic complete response (pCR) after neoadjuvant chemotherapy could help identify those who could safely be spared the potential morbidity of axillary lymph node dissection. We performed a retrospective analysis of a cohort of clinically node-positive patients managed with neoadjuvant chemotherapy with the goal of identifying predictors of axillary pCR.

Methods:

Eligible patients were aged 18 years or older, had clinical T1–T4, N1–N3, M0 breast cancer and received neoadjuvant chemotherapy followed by surgical axillary lymph node staging between 2001 and 2017 at Misericordia Hospital, Edmonton, Alberta. Patient data, including tumour characteristics, details of neoadjuvant chemotherapy, imaging results before and after neoadjuvant chemotherapy, and final pathologic analysis, were collected from the appropriate provincial electronic data repositories. We summarized the data using descriptive statistics. We characterized associations between clinical/tumour characteristics and pCR using univariate and multivariate regression analysis.

Results:

Of the 323 patients included in the study, 130 (40.2%) achieved axillary pCR. Absence of residual disease in the breast was associated with axillary pCR (odds ratio 6.74, 95% confidence interval 2.89–15.67). HER2-positive, triple-negative and ER-positive/PR-negative/HER2-negative tumours were significantly associated with a pCR on univariate analysis; the association trended toward significance on multivariate analysis.

Conclusion:

Our findings support the routine use of neoadjuvant chemotherapy and sentinel lymph node biopsy in patients with an absence of residual disease in the breast, and potentially in those with HER2-positive or triple-negative subtypes, and highlight the ER-positive/PR-negative biomarker subtype as a potential predictor of nodal response.

Pathological Response in the Breast and Axillary Lymph Nodes after Neoadjuvant Systemic Treatment in Patients with Initially Node-Positive Breast Cancer Correlates with Disease Free Survival: An Exploratory Analysis of the GeparOcto Trial

Simple Summary

The extent of axillary surgery has been reduced in recent years to minimize side effects. However, a negative impact of reduced surgery on outcome must be avoided. We investigated for whom the extent of surgery can be safely reduced by examining early-stage breast cancer patients converting from lymph node (LN)-positive to LN-negative disease after neoadjuvant systemic treatment (NAST). Of 242 initially LN-positive patients treated within the GeparOcto trial, 54.5% were classified as LN-negative after NAST, 31.8% as LN-positive, and for 13.6% data were missing. Overall, 92.1% of patients underwent complete axillary LN dissection, with 6.6% undergoing sentinel LN dissection only. At surgery, 55.4% of patients had no signs of cancer in the LN, 45.0% had no signs of cancer in the breast (of those 8.3% had involved LN), and 41.3% had no signs of cancer at all. Patients with involved LN still had a bad prognosis. Conversion from LN-positive to LN-negative after NAST is of highest prognostic value. Surgical axillary staging after NAST is essential in these patients to offer tailored treatment.

Abstract

Background: The conversion of initially histologically confirmed axillary lymph node-positive (pN+) to ypN0 after neoadjuvant systemic treatment (NAST) is an important prognostic factor in breast cancer (BC) patients and may influence surgical de-escalation strategies. We aimed to determine pCR rates in lymph nodes (pCR-LN), the breast (pCR-B), and both (tpCR) in women who present with pN+ BC, to assess predictors for response and the impact of pCR-LN, pCR-B, and tpCR on invasive disease-free survival (iDFS). Methods: Retrospective, exploratory analysis of 242 patients with pN+ at diagnosis from the multicentric, randomized GeparOcto trial. Results: Of 242 patients with initially pN+ disease, 134 (55.4%) had a pCR-LN, and 109 (45.0%) a pCR-B. Of the 109 pCR-B patients, 9 (8.3%) patients had involved LN, and 100 (41.3%) patients had tpCR. Those with involved LN still had a bad prognosis. As expected, pCR-B and intrinsic subtypes (TNBC and HER2+) were identified as independent predictors of pCR-LN. pCR-LN (ypN0; hazard ratio 0.42; 95%, CI 0.23–0.75; p = 0.0028 for iDFS) was the strongest independent prognostic factor. Conclusions: In initially pN+ patients undergoing NAST, the conversion to ypN0 is of high prognostic value. Surgical axillary staging after NAST is still essential in these patients to offer tailored treatment.

Positive ROS (Reactive Oxygen Species) Modulator Engineered Device Support Skin Treatment in Locally Advanced Breast Cancer (LABC) Enhancing Patient Quality of Life

The development of research in genetic and biochemical fields has made it possible to investigate certain metabolic aspects of the microenvironment of chronic skin lesions, including altered cell signalling, highlighting its importance in determining the blockage of repair processes. The purpose of this prospective observational study is to evaluate the efficacy of a medical device consisting of a polyester scaffold enriched with an oleic matrix with controlled release of ROS in the management of LABC skin lesions. During the period from October 2018 to March 2020, 20 patients with locally advanced breast cancer were enrolled and ten were treated with the devices abovementioned. After 30 days of treatment all patients treated reported a general improvement in local conditions with reduction in ulceration area, exudate and odour. The results suggest that the application of these devices even in particular conditions (healthy and neoplastic tissue) does not lead to the onset of negative effects due to the release of ROS, though their role in tissue repair requires further study to fully understand their potential and increase the fields of application of the device by exploiting its modulation capabilities.

Image-Guided Breast Interventions: Biopsy and Beyond

Breast interventions primarily comprise of biopsy of the suspicious breast lesions to obtain accurate pathological diagnosis. Generally, image-guided breast biopsy is required for nonpalpable lesions, however, even in palpable lesions, image-guided biopsy should be performed as it improves the accuracy of diagnosis. Image-guided breast interventions have progressed well beyond biopsy, making the radiologist an important part of the multidisciplinary management of breast cancer. Preoperative localization of nonpalpable abnormalities guides optimal surgical excision to obtain negative margins without sacrificing the normal tissue. Ablative procedures for breast cancer treatment such as radiofrequency ablation (RFA) and high-intensity focused ultrasound ablation can sometimes replace surgery in older patients with comorbidities. This article enumerates and describes the expanding spectrum of image-guided interventions performed by breast radiologist.

Postmastectomy radiation therapy following pathologic complete nodal response to neoadjuvant chemotherapy: A prelude to NSABP B-51?

PURPOSE

The utility of post-mastectomy radiotherapy (PMRT) in women with a nodal complete response (CRn) to neoadjuvant chemotherapy (NAC) is unknown. The NSABP B-51 trial is evaluating this question, but has not reported results thus far. Therefore, we sought to answer this question with the National Cancer Database.

METHODS

The National Cancer Database was queried for women with cT1-4N1-3M0 breast cancer who had undergone NAC and were ypN0 upon mastectomy. Statistics included multivariable logistic regression, Kaplan-Meier overall survival (OS) analysis, Cox proportional hazards modeling, and construction of forest plots.

RESULTS

Of 14,690 women, 10,092 (69%) underwent adjuvant PMRT and 4598 (31%) did not. The median follow-up was 55.6 months. In all patients, the 10-year OS was 76.3% for PMRT and 78.6% without (p = 0.412). There were no notable effects of PMRT on OS based on age or the axillary management (number of nodes removed). Specifically, in the NSABP B-51 population of cT1-3 cN1 patients, the 10-year OS was 82.6% for PMRT and 80.0% without (p = 0.250). PMRT benefitted women with increasing cT stage (i.e. cT3-4), increasing ypT stages (with the exception of ypT4 potentially owing to small sample sizes), and cN3 cases (p < 0.05 for all).

CONCLUSIONS

In the absence of published results from NSABP B-51, this assessment of over 14,000 women from a contemporary US database revealed that PMRT may be most useful for a "moderately-high" risk group - women with more advanced primary and/or nodal disease at diagnosis, yet with tumor biology favorable enough that the disease does not progress or remain stable after NAC. The OS findings notwithstanding, this study cannot exclude potential differences between groups in recurrence-free survival, which is the primary endpoint of NSABP B-51, While the results of the NSABP B-51 will confirm optimal management for patients with limited nodal disease having a CRn following NAC, the present results suggest PMRT should remain the standard of care for more advanced disease than NSABP B-51 eligibility criteria.

Survival in Cytologically Proven Node-Positive Breast Cancer Patients with Nodal Pathological Complete Response after Neoadjuvant Chemotherapy

BACKGROUND

It is unknown whether patients with cytologically proven axillary node-positive breast cancer who achieve axillary pathological complete response (pCR) after neoadjuvant chemotherapy (NAC) have comparable prognosis to patients with axillary pathological node-negative disease (pN-) without NAC.

METHODS

We retrospectively reviewed the data of patients with cytologically proven axillary node-positive disease who received NAC and those with axillary pN- without NAC for control between January 2007 and December 2012. We compared outcomes according to response in the axilla to NAC and between patients with axillary pCR and matched pairs with axillary pN- without NAC using propensity scores.

RESULTS

We included 596 patients with node-positive breast cancer who received NAC. The median follow-up period was 64 months. Patients with axillary pCR showed significantly better distant disease-free survival (DDFS) and overall survival (OS) than patients with residual axillary disease (both p < 0.01). There was no significant difference in DDFS and OS between patients with axillary pCR and matched pairs with axillary pN- without NAC.

CONCLUSION

Axillary pCR was associated with improved prognosis. Patients with axillary pCR and matched pairs with axillary pN- without NAC had comparable outcomes. This information will be useful when considering the intensity of follow-up and adjuvant therapy.

Feasibility of Axillary Lymph Node Localization and Excision Using Radar Reflector Localization

INTRODUCTION

Neoadjuvant chemotherapy (NAC) is commonly used for patients with clinically detected nodal metastases. Sentinel lymph node biopsy (SLNB) after NAC is feasible. Excision of biopsy-proven positive lymph nodes in addition to SLNB, termed targeted axillary dissection (TAD), decreases the false-negative rate of SLNB alone. Positive nodes can be marked with radar reflector-localization (RRL) clips. We report our institutional experience with RRL-guided TAD and demonstrate its safety and feasibility.

PATIENTS AND METHODS

We performed an institutional review board-approved retrospective review of consecutive clinically node-positive female patients with breast cancer treated with NAC and RRL-guided TAD between January 2017 and September 2019. Clinicopathologic and treatment data were collected; descriptive statistics are reported.

RESULTS

Forty-five patients were analyzed; the median age was 55 years (range, 20-72 years), and the median body mass index was 27.2 kg/m² (range, 16.5-40.4 kg/m²). All patients received NAC, primary breast surgery, and TAD. All clinically detected nodal metastases were confirmed with percutaneous biopsy and marked with a biopsy clip. RRL clips were implanted a median of 8 days (range, 1-167 days) prior to surgery; all were retrieved without complications. The RRL node was identified as the sentinel lymph node in 36 (80%) patients. Twenty-five patients had positive nodes, of which 24 were identified by RRL node excision, and 1 (4%) patient had a positive node identified by SLNB but not RRL. Over a median follow-up time of 29.6 months, 5 patients recurred (1 local, 4 distant).

CONCLUSIONS

RRL-guided TAD after NAC is safe and feasible. This technique allows for adequate assessment of the nodal basin and helps confirm excision of the previously biopsied positive axillary node.

Is breast conserving therapy better than mastectomy? Surgeons must speak out

Several population-based studies suggest that breast conserving surgery followed by radiotherapy (BCT) may provide longer overall survival than mastectomy. Better locoregional control after BCT due to improvements of preoperative imaging, oncoplastic surgery and radiotherapy, as well as the recent trend towards surgical de-escalation may be involved. Alternatively, modern radiotherapy may have such an improved benefit/risk ratio that its survival advantage now stands out more clearly. However, since the therapeutic equivalence of BCT and mastectomy was demonstrated by several randomised trials, this information cannot be disregarded, nor radiotherapy should be used to compensate for inadequate surgery. Both BCT and mastectomy are likely here to stay as clinical presentation of breast cancer is highly variable, and women desires may transcend a rational balance of pros and cons between the two surgical approaches. Our duty as surgeons is to lead the multidisciplinary board and accompany the patients along this difficult decision-making process.