SINODAR ONE, an ongoing randomized clinical trial to assess the role of axillary surgery in breast cancer patients with one or two macrometastatic sentinel nodes

Quality assessment of radiotherapy in the prospective randomized SENOMAC trial

BACKGROUND AND PURPOSE

Recommendations for regional radiotherapy (RT) of sentinel lymph node (SLN)-positive breast cancer are debated. We here report a RT quality assessment of the SENOMAC trial.

MATERIALS AND METHODS

The SENOMAC trial randomized clinically node-negative breast cancer patients with 1-2 SLN macrometastases to completion axillary lymph node dissection (cALND) or SLN biopsy only between 2015-2021. Adjuvant RT followed national guidelines. RT plans for patients included in Sweden and Denmark until June 2019 were collected (N = 1176) and compared to case report forms (CRF). Dose to level I (N = 270) and the humeral head (N = 321) was analyzed in detail.

RESULTS

CRF-data and RT plans agreed in 99.3 % (breast/chest wall) and in 96.6 % of patients (regional RT). Congruence for whether level I was an intended RT target was lower (78 %). In accordance with Danish national guidelines, level I was more often an intended target in the SLN biopsy only arm (N = 334/611, 55 %,) than in the cALND arm (N = 174/565, 31 %,). When an intended target, level I received prescribed dose to 100 % (IQR 98-100 %) of the volume. However, even when not an intended target, full dose was delivered to > 80 % of level I (IQR 75-90 %). The intentional inclusion of level I in the target volume more than doubled the dose received by ≥ 50 % of the humeral head.

CONCLUSION

Congruence between CRF data and RT plans was excellent. Level I received a high dose coverage even when not intentionally included in the target. Including level I in target significantly increased dose to the humeral head.

Trends of Axillary Treatment in Sentinel Node-Positive Breast Cancer Patients Undergoing Mastectomy

BACKGROUND

The ACOSOG-Z0011- and the AMAROS-trial obviated the need for axillary surgery in most sentinel node-positive (SLN+) breast cancer patients undergoing breast-conserving surgery (BCS). Data for patients who undergo mastectomy is scarce. The purpose of this study was to investigate patterns of axillary treatment in SLN+ patients treated by mastectomy in the years after the publication of landmark studies regarding axillary treatment in SLN+ breast cancer patients undergoing BCS.

METHODS

This was a population-based study in cT1-3N0M0 breast cancer patients treated by mastectomy and staged as SLN+ between 2009 and 2018. The performance of an axillary lymph node dissection (ALND) and/or administration of postmastectomy radiotherapy (PMRT) were primary outcomes and were studied over time.

RESULTS

The study included 10,633 patients. The frequency of ALND performance decreased from 78% in 2009 to 10% in 2018, whereas PMRT increased from 4 to 49% (P < 0.001). In ≥N1a patients, ALND performance decreased from 93 to 20%, whereas PMRT increased to 70% (P < 0.001). In N1mi and N0itc patients, ALND was abandoned during the study period, whereas PMRT increased to 38% and 13% respectively (P < 0.001), respectively. Age, tumor subtype, N-stage, and hospital type affected the likelihood that patients underwent ALND.

CONCLUSIONS

In this study in SLN+ breast cancer patients undergoing mastectomy, use of ALND decreased drastically over time. By the end of 2018 most ≥N1a patients received PMRT as the only adjuvant axillary treatment, whereas the majority of N1mi and N0itc patients received no additional treatment.

Sentinel lymph node biopsy versus axillary lymph node dissection in breast cancer patients undergoing mastectomy with one to two metastatic sentinel lymph nodes: sub-analysis of the SINODAR-ONE multicentre randomized clinical trial and reopening of enrolment

BACKGROUND

The initial results of the SINODAR-ONE randomized clinical trial reported that patients with T1-2 breast cancer and one to two macrometastatic sentinel lymph nodes treated with breast-conserving surgery, sentinel lymph node biopsy only, and adjuvant therapy did not present worse 3-year survival, regional recurrence, or distant recurrence rates compared with those treated with axillary lymph node dissection. To extend the recommendation of axillary lymph node dissection omission even in patients treated with mastectomy, a sub-analysis of the SINODAR-ONE trial is presented here.

METHODS

Patients with T1-2 breast cancer and no more than two metastatic sentinel lymph nodes undergoing mastectomy were analysed. After sentinel lymph node biopsy, patients were randomly assigned to receive either axillary lymph node dissection followed by adjuvant treatment (standard arm) or adjuvant treatment alone (experimental arm). The primary endpoint was overall survival. The secondary endpoint was recurrence-free survival.

RESULTS

A total of 218 patients were treated with mastectomy; 111 were randomly assigned to the axillary lymph node dissection group and 107 to the sentinel lymph node biopsy-only group. At a median follow-up of 33.0 months, there were three deaths (two deaths in the axillary lymph node dissection group and one death in the sentinel lymph node biopsy-only group). There were five recurrences in each treatment arm. No axillary lymph node recurrence was observed. The 5-year overall survival rates were 97.8 and 98.7 per cent in the axillary lymph node dissection treatment arm and the sentinel lymph node biopsy-only treatment arm, respectively (P = 0.597). The 5-year recurrence-free survival rates were 95.7 and 94.1 per cent in the axillary lymph node dissection treatment arm and the sentinel lymph node biopsy treatment arm, respectively (P = 0.821).

CONCLUSION

In patients with T1-2 breast cancer and one to two macrometastatic sentinel lymph nodes treated with mastectomy, the overall survival and recurrence-free survival rates of patients treated with sentinel lymph node biopsy only were not inferior to those treated with axillary lymph node dissection. To strengthen the conclusion of the trial, the enrolment of patients treated with mastectomy was reopened as a single-arm experimental study.

REGISTRATION NUMBER

NCT05160324 (http://www.clinicaltrials.gov).

Nonsentinel Axillary Lymph Node Status in Clinically Node-Negative Early Breast Cancer After Primary Systemic Therapy and Positive Sentinel Lymph Node: A Predictive Model Proposal

BACKGROUND

In clinically node-negative (cN0) early stage breast cancer (EBC) undergoing primary systemic treatment (PST), post-treatment positive sentinel lymph node (SLN+) directs axillary lymph node dissection (ALND), with uncertain impacts on outcomes and increased morbidities.

PATIENTS AND METHODS

We conducted an observational study on imaging-confirmed cN0 EBC, who underwent PST and breast surgery that resulted in SLN+ and underwent ALND. The association among baseline/postsurgical clinic-pathological factors and positive nonsentinel additional axillary lymph nodes (non-SLN+) was analyzed with logistic regression. LASSO regression (LR) identified variables to include in a predictive score of non-SLN+ (ALND-predict). The accuracy and calibration were assessed, an optimal cut-point was then identified, and in silico validation with bootstrap was undertaken.

RESULTS

Non-SLN+ were detected in 22.2% cases after ALND. Only progesterone receptor (PR) levels and macrometastatic SLN+ were independently associated to non-SLN+. LR identified PR, Ki67, and type and number of SLN+ as the most efficient covariates. The ALND-predict score was built based on their LR coefficients, showing an area under the curve (AUC) of 0.83 and an optimal cut-off of 63, with a negative predictive value (NPV) of 0.925. Continuous and dichotomic scores had a good fit (p = 0.876 and p = 1.00, respectively) and were independently associated to non-SLN+ [adjusted odds ratio (aOR): 1.06, p = 0.002 and aOR: 23.77, p < 0.001, respectively]. After 5000 bootstrap-adjusted retesting, the estimated bias-corrected and accelerated 95%CI included the aOR.

CONCLUSIONS

In cN0 EBC with post-PST SLN+, non-SLN+ at ALND are infrequent (~22%) and independently associated to PR levels and macrometastatic SLN. ALND-predict multiparametric score accurately predicted absence of non-SLN involvement, identifying most patients who could be safely spared unnecessary ALND. Prospective validation is required.

The need to tailor the omission of axillary lymph node dissection to patients with good prognosis and sentinel node micro-metastases

BACKGROUND

Results of IBCSG-23-01-trial which included breast cancer patients with involved sentinel nodes (SN) by isolated-tumor-cells or micro-metastases supported the non-inferiority of completion axillary-lymph-node-dissection (cALND) omission. However, current data are considered insufficient to avoid cALND for all patients with SN-micro-metastases.

METHODS

To investigate the impact of cALND omission on disease-free-survival (DFS) and overall survival (OS), we analyzed a cohort of 1421 patients <75 years old with SN-micro-metastases who underwent breast conservative surgery (BCS). We used inverse probability of treatment weighting (IPTW) to obtain adjusted Kaplan-Meier estimators representing the experience in the analysis cohort, based on whether all or none had been subject to cALND omission.

RESULTS

Weighted log-rank tests comparing adjusted Kaplan-Meier survival curves showed significant differences in OS (p-value = 0.002) and borderline significant differences in DFS (p-value = 0.090) between cALND omission versus cALND. Cox's regression using stabilized IPTW evidenced an average increase in the risk of death associated with cALND omission (HR = 2.77, CI95% = 1.36-5.66). Subgroup analyses suggest that the rates of recurrence and death associated with cALND omission increase substantially after a large period of time in the half sample of women less likely to miss cALND.

CONCLUSIONS

Using IPTW to estimate the causal treatment effect of cALND in a large retrospective cohort, we concluded cALND omission is associated with an increased risk of recurrence and death in women of <75 years old treated by BCS in the absence of a large consensus in favor of omitting cALND. These results are particularly contributive for patients treated by BCS where cALND omission rates increase over time.

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.

Axillary management for early invasive breast cancer patients: Who will truly benefit?

Background

The implementation of sentinel lymph node biopsy (SLNB) and further completion axillary lymph node dissection (cALND) after positive sentinel lymph nodes (SLNs) on early invasive breast cancer patients should be cautiously tailored. Identifying predictors for SLN and non-sentinel lymph node (nSLN) metastases can help surgeons make better surgical decisions.

Methods

A retrospective case-control study was designed and a total of 560 eligible patients were enrolled consecutively. They were all diagnosed in our center and received appropriate medical care. According to the metastasis of SLN and nSLN, they were divided into metastatic and non-metastatic groups on two successive occasions to investigate the relationship between clinical factors, pathological factors, hematological factors and lymph node metastasis.

Results

In total, 101 (18.04%) patients developed SLN metastases, including 98 patients with macro-metastases and 3 patients with micro-metastases. Out of 97 patients receiving further cALND, 20 patients (20.62%) developed nSLN metastases. Multivariate analysis revealed that “high expression of Ki-67” and “lymphatic invasion” predicted a higher risk of SLN metastasis; and “increased number of positive SLNs” and “increased systemic inflammation index (SII)” predicted a higher risk of nSLN metastasis.

Conclusion

Surgery for early invasive breast cancer patients should be more customized and precise. Appropriate axillary management is necessary for patients with the associated predictors.

Locoregional Management of Breast Cancer: A Chronological Review

Locoregional management of breast cancer is founded on evidence generated over a vast time period, much longer than the career span of many practicing physicians. Oncologists rely on specific patient and tumour characteristics to recommend modern-day treatments. However, some of this information may not have been available during prior periods in which the evidence was generated. For example, the comprehensive Early Breast Cancer Trialists’ Collaborative Group (EBCTCG) meta-analyses published in the 2000s typically included older trials accruing patients between the 1960s and 1980s. This raises some uncertainty about whether conclusions from studies conducted in prior eras are as relevant or applicable to modern-day patients and treatments. Reviewing the chronological order and details of the evidence can be beneficial to understanding these nuances. This review discusses the evolution of locoregional management through some key clinical trials. We aim to highlight the time period in which the evidence was generated and emphasize the 10-year outcomes for the comparability of results. Evidence supporting surgical management of the breast and axilla, as well as details of radiotherapy are discussed briefly for all stages of breast cancer.

Preservation of Axillary Lymph Nodes Compared with Complete Dissection in T1-2 Breast Cancer Patients Presenting One or Two Metastatic Sentinel Lymph Nodes: The SINODAR-ONE Multicenter Randomized Clinical Trial

BACKGROUND

The SINODAR-ONE trial is a prospective noninferiority multicenter randomized study aimed at assessing the role of axillary lymph node dissection (ALND) in patients undergoing either breast-conserving surgery or mastectomy for T1-2 breast cancer (BC) and presenting one or two macrometastatic sentinel lymph nodes (SLNs). The endpoints were to evaluate whether SLN biopsy (SLNB) only was associated with worsening of the prognosis compared with ALND in terms of overall survival (OS) and relapse.

METHODS

Patients were randomly assigned (1:1 ratio) to either removal of ≥ 10 axillary level I/II non-SLNs followed by adjuvant therapy (standard arm) or no further axillary treatment (experimental arm).

RESULTS

The trial started in April 2015 and ceased in April 2020, involving 889 patients. Median follow-up was 34.0 months. There were eight deaths (ALND, 4; SNLB only, 4), with 5-year cumulative mortality of 5.8% and 2.1% in the standard and experimental arm, respectively (p = 0.984). There were 26 recurrences (ALND 11; SNLB only, 15), with 5-year cumulative incidence of recurrence of 6.9% and 3.3% in the standard and experimental arm, respectively (p = 0.444). Only one axillary lymph node recurrence was observed in each arm. The 5-year OS rates were 98.9% and 98.8%, in the ALND and SNLB-only arm, respectively (p = 0.936).

CONCLUSIONS

The 3-year survival and relapse rates of T1-2 BC patients with one or two macrometastatic SLNs treated with SLNB only, and adjuvant therapy, were not inferior to those of patients treated with ALND. These results do not support the use of routine ALND.

Contemporary Axillary Management in cT1-2N0 Breast Cancer with One or Two Positive Sentinel Lymph Nodes: Factors Associated with Completion Axillary Lymph Node Dissection Within the National Cancer Database

BACKGROUND

Management of the axilla in patients with cT1-2N0 breast cancer with one or two positive (+) sentinel lymph nodes (SLNs) is often debated, especially in patients undergoing mastectomy. In 2018, the National Cancer Database (NCDB) began collecting the number of +SLNs, enabling identification of patients with one or two +SLNs for the first time.

METHODS

From the 2018 NCDB participant user file (PUF), all cT1-2N0M0 patients with one or two +SLNs were identified. The rates of completion axillary lymph node dissection (cALND) after breast-conserving surgery (BCS) and mastectomy were determined, and logistic regression was used to assess factors associated with cALND.

RESULTS

Of 10,531 patients with one or two +SLNs, cALND was performed in 807/6498 (12.4%) BCS patients and 1845/4033 (45.7%) mastectomy patients (p < 0.001). Factors associated with cALND in BCS were cT2 versus cT1 (16.0% versus 11.1%, p < 0.001), two versus one positive SLN (20.7% versus 10.8%, p < 0.001), and higher tumor grade (grade 3: 15.4% versus grade 1-2: 11.7%, p = 0.002). Factors associated with cALND among mastectomy were cT2 versus cT1 (48.2% versus 43.7%, p = 0.004), two versus one positive SLN (56.6% versus 42.8%, p < 0.001), younger age (age < 50 years: 49.0%, age 50+ years: 44.1%, p = 0.004), and Hispanic ethnicity (55.7% versus 45.1%, p = 0.001). After adjusting for pN category, adjuvant radiation was significantly less likely after mastectomy if cALND was performed (odds ratio (OR) 0.51, p < 0.001).

CONCLUSIONS

Omission of cALND with one or two +SLNs in BCS is common. Deescalation of axillary therapy in mastectomy is slower, with a cALND rate of 45.7% in 2018. With the recent updates to the National Cancer Care Network (NCCN) guidelines, we anticipate continued deescalation of axillary therapy in mastectomy patients.

De-escalating axillary surgery in early-stage breast cancer

The role of axillary surgery has evolved over the last three decades from routine axillary lymph node dissection (ALND) to sentinel lymph node biopsy to omission of axillary surgery altogether in select patients. This evolution has been achieved through the design and conduct of multiple clinical trials demonstrating that ALND does not impact survival and is not necessary for local control in patients with early-stage breast cancer and limited nodal involvement. Importantly, this practice-changing shift mirrored the trend towards earlier stage at diagnosis and the recognition of the interplay between local and systemic therapies in maintaining local control. There are numerous clinical scenarios today in which axillary staging can be safely avoided, including (1) DCIS treated with lumpectomy, (2) at the time of contralateral prophylactic mastectomy, and (3) in elderly patients with early-stage, HR+/HER2-clinically node-negative (cN0) disease. Ongoing clinical trials seek to expand the cohorts in which surgical nodal staging can be omitted. These populations include a broader range of early-stage, cN0 patients undergoing upfront surgery, as seen in the SOUND, INSEMA, BOOG 2013-08, SOAPET and NAUTILUS trials. Omission of axillary surgery in cN0 patients with HER2+ or triple-negative disease treated with neoadjuvant chemotherapy is also being tested in the ASICS and EUBREAST-01 trials. Continued advances in imaging and the growing role of genomic assays in selecting patients for systemic therapy are likely to further minimize the need for axillary surgery; thereby further reducing the morbidity of local therapy for women with breast cancer.

Axillary Ultrasound Evaluation in Breast Cancer Patients: A Multidisciplinary Viewpoint and Middle Ground

Over the past decade, there has been a trend toward de-escalation of axillary surgery. Certain patients may now forego axillary lymph node dissection even in the setting of a positive sentinel lymph node biopsy (SLNB), and some patients may not even undergo a SLNB. However, there is wide variability in the imaging approach to assessing axillary lymph nodes in patients with breast cancer. Approaches range from performing axillary US in all patients with newly diagnosed breast cancer to omitting axillary imaging evaluation in all patients. This article provides a multidisciplinary middle ground approach for axillary nodal evaluation. The clinical impact and rationale for appropriate axillary nodal imaging are discussed and an imaging algorithm is proposed.

Sentinel node involvement with or without completion axillary lymph node dissection: treatment and pathologic results of randomized SERC trial

Based on results of clinical trials, completion ALND (cALND) is frequently not performed for patients with breast conservation therapy and one or two involved sentinel nodes (SN) by micro- or macro-metastases. However, there were limitations despite a conclusion of non-inferiority for cALND omission. No trial had included patients with SN macro-metastases and total mastectomy or with >2 SN macro-metastases. The aim of the study was too analyze treatment delivered and pathologic results of patients included in SERC trial. SERC trial is a multicenter randomized non-inferiority phase-3 trial comparing no cALND with cALND in cT0-1-2, cN0 patients with SN ITC (isolated tumor cells) or micro-metastases or macro-metastases, mastectomy or breast conservative surgery. We randomized 1855 patients, 929 to receive cALND and 926 SLNB alone. No significant differences in patient’s and tumor characteristics, type of surgery, and adjuvant chemotherapy (AC) were observed between the two arms. Rates of involved SN nodes by ITC, micro-metastases, and macro-metastases were 5.91%, 28.12%, and 65.97%, respectively, without significant difference between two arms for all criteria. In multivariate analysis, two factors were associated with higher positive non-SN rate: no AC versus AC administered after ALND (OR = 3.32, p < 0.0001) and >2 involved SN versus ≤2 (OR = 3.45, p = 0.0258). Crude rates of positive NSN were 17.62% (74/420) and 26.45% (73/276) for patient’s eligible and non-eligible to ACOSOG-Z0011 trial. No significant differences in patient’s and tumor characteristics and treatment delivered were observed between the two arms. Higher positive-NSN rate was observed for patients with AC performed after ALND (17.65% for SN micro-metastases, 35.22% for SN macro-metastases) in comparison with AC administered before ALND.

Macrometastasis at selective lymph node biopsy: A practical going-for-the-one clinical scoring system to personalize decision making

BACKGROUND

Axillary sentinel lymph node biopsy (SLNB) is standard treatment for patients with clinically and pathological negative lymph nodes. However, the role of completion axillary lymph node dissection (cALND) following positive sentinel lymph node biopsy (SLNB) is debated.

AIM

To identify a subgroup of women with high axillary tumor burden undergoing SLNB in whom cALND can be safely omitted in order to reduce the risk of long-term complications and create a Preoperative Clinical Risk Index (PCRI) that helps us in our clinical practice to optimize the selection of these patients.

METHODS

Patients with positive SLNB who underwent a cALND were included in this study. Univariate and multivariate analysis of prognostic and predictive factors were used to create a PCRI for safely omitting cALND.

RESULTS

From May 2007 to April 2014, we performed 1140 SLN biopsies, of which 125 were positive for tumor and justified to practice a posterior cALND. Pathologic findings at SLNB were micrometastases (mic) in 29 cases (23.4%) and macrometastasis (MAC) in 95 cases (76.6%). On univariate analysis of the 95 patients with MAC, statistically significant factors included: age, grade, phenotype, histology, lymphovascular invasion, lymph-node tumor size, and number of positive SLN. On multivariate analysis, only lymph-node tumor size (≤ 20 mm) and number of positive SLN (> 1) retained significance. A numerical tool was created giving each of the parameters a value to predict preoperatively which patients would not benefit from cALND. Patients with a PCRI ≤ 15 has low probability (< 10%) of having additional lymph node involvement, a PRCI between 15-17.6 has a probability of 43%, and the probability increases to 69% in patients with a PCRI > 17.6.

CONCLUSION

The PCRI seems to be a useful tool to prospectively estimate the risk of nodal involvement after positive SLN and to identify those patients who could omit cALND. Further prospective studies are necessary to validate PCRI clinical generalization.

A National Survey of Breast Surgeons and Radiation Oncologists on Contemporary Axillary Management in Mastectomy Patients

BACKGROUND

Management of axillary lymph nodes in breast cancer has undergone significant change over the past decade through landmark clinical trials. This study aimed to assess national practice patterns in axillary management in patients undergoing upfront mastectomy and examines what guides provider recommendations.

METHODS

A national case-based survey study was performed of surgeons and radiation oncologists from July to August 2020. Surgeons were identified through the American Society of Breast Surgeons (ASBrS) after review and approval by the ASBrS Research Committee, and radiation oncologists were identified through an institutional database. Both descriptive and comparative statistical analyses were performed.

RESULTS

Overall, 994 providers responded-680 surgeons and 314 radiation oncologists. Surgeons were older and in practice longer (p < 0.05) and treated a higher percentage of breast patients (81% vs. 40%, p < 0.001). Most surgeons were hospital-employed (43%), whereas most radiation oncologists were in private practice (40%; p < 0.001). Fifty-two percent of surgeons routinely send sentinel lymph nodes (SLNs) for frozen section (52%) during mastectomy, of which 78% proceed directly to axillary lymph node dissection (ALND) if positive. There was significant variability in treatment recommendations between the two groups among the hypothetical cases (p < 0.001). In the setting of low disease burden in the SLNs, > 30% of surgeons recommended ALND, while radiation oncologists recommend axillary radiotherapy over axillary clearance (p < 0.001).

CONCLUSION

There is significant heterogeneity in the management of the axilla in mastectomy patients with pathologically positive SLNs, both between and among surgeons and radiation oncologists. Efforts should be made to assist both groups in identifying de-escalation opportunities to ensure that mastectomy patients with positive SLNs are treated appropriately.

Lymph nodal radiotherapy in breast cancer: what are the unresolved issues?

Introduction: Sentinel lymph node biopsy (SLNB) is the gold standard in invasive breast cancer. Axillary dissection (ALND) is controversial in some presentations.Areas covered: Key questions were formulated and explored focused on four different scenarios in adjuvant axillary radiation management in early and locally advanced breast cancer. Answers to these questions were searched in MEDLINE, PubMed from June 1946 to August 2020. Clinical trials, retrospective studies, international guidelines, meta-analysis, and reviews were explored.Expert opinion: Analysis according to biological disease characteristics is necessary to establish the impact of ALND avoidance in unexpectedly positive SLNB (pN1) in cN0 patients. A low-risk probability of axillary recurrence was observed if axillary radiotherapy (ART) or ALND were offered without impact on outcomes. Adjuvant RNI in pT1-3 pN1 treated with mastectomy or BCS should be proposed in unfavorable disease and risk factors. In ycN0 after NACT, SLNB can be offered in selected cases or ALND should be performed. After SLNB post-NACT (ypN1), ALND and adjuvant radiotherapy are mandatory.

Women Could Avoid Axillary Lymph Node Dissection by Choosing Breast-Conserving Therapy Instead of Mastectomy

BACKGROUND

The ACOSOG Z0011 trial showed that completion axillary lymph node dissection (cALND) can be safely omitted for some patients with T1-2 clinically node-negative breast cancer with one to two involved sentinel lymph nodes (SLNs) treated with breast-conserving therapy (BCT). There is little evidence for the safety of omitting cALND for mastectomy-treated patients. Consequently, cALND is often recommended for sentinel node-positive patients treated with mastectomy. The aim of this study is to determine the proportion of patients who could avoid cALND by choosing BCT instead of mastectomy at a tertiary cancer center.

PATIENTS AND METHODS

All T1-2 clinically node-negative breast cancer patients treated with BCT or mastectomy between 2012 and 2017 with metastases in the SLN(s) were selected from a prospectively maintained database. Clinical factors and outcomes were evaluated between the two groups. Differences were compared using Wilcoxon rank-sum test, chi-square test or Fisher's exact test as appropriate. Significance was set at the 0.05 level for all analyses.

RESULTS

A total of 306 patients were included, 199 (65.0%) of whom were treated with BCT and 107 (35.0%) with mastectomy. Patients treated with mastectomy were more often treated with cALND compared with those treated with BCT (71.0% versus 26.6%, p < 0.0001). Overall, 52 of the mastectomy patients (68.4%) could have avoided cALND if they had chosen BCT.

CONCLUSIONS

Patients treated with mastectomy are more likely to receive cALND than those treated with BCT. Axillary management should be addressed during discussion of primary tumor therapy, and cALND may be avoided when patients choose BCT instead of mastectomy.

Ongoing clinical trials on axillary management

INTRODUCTION

Within the last 50 years the management of patients with breast cancer has changed dramatically with a significant de-escalation of the role and magnitude of surgery, both for the management of the primary tumor and for the management of the axilla. In the management of the axilla of patients with early stage breast cancer (EBC) and clinically uninvolved axilla (cN0), axillary lymph node dissection (ALND) was gradually replaced by sentinel lymph node biopsy (SLNB) saving more than 60-70% of patients from an unnecessary dissection. Further studies confirmed that isolated tumor cells or micrometastases found on the SLN had no further benefit from ALND sparing even more patients from an unnecessary ALND. Eventually, the Z0011 and other studies showed that even patients with 1-2 positive SLN can be spared from ALND provided they fulfill certain criteria. Still though there were many flaws in these studies and further research was necessary to generalize the results of these studies to a wider target group. Meanwhile, there is a clear view that many low risk patients if they have their axilla evaluated via US and are not found to have suspicious nodes, it is highly unlikely to have involved axilla. This let to studies evaluating the non-surgical management of the axilla. Finally, in the post neoadjuvant setting 3 randomized controlled trials showed that under certain circumstances SLNB can be done after the NAC even in patients who initially had involved axilla and was converted to clinically uninvolved (cN1→cN0).

EVIDENCE ACQUISITION

PubMed, Medline, the Cochrane Library Controlled Trials Register as well as National Institutes of Health ClinicalTrials.Gov database have been consulted up to May 2020.

EVIDENCE SYNTHESIS

We studied and described the ongoing trials on patients not undergoing neoadjuvant chemotherapy and we discussed the eligibility criteria, the comparison arms and the expected outcomes. We further examined the ongoing trials on patients undergoing neoadjuvant chemotherapy in the same manner.

CONCLUSIONS

Although we have covered a long way in the journey of eliminating axillary surgery, there are still lots of questions to be answered and trials to be conducted. We anticipate the results of the ongoing trials to provide the necessary evidence to safely de-escalate more the axillary surgery, both in the non-neoadjuvant as well as in the neoadjuvant setting, hoping that in the not so far future the axillary surgery will eventually perish.

Updates on the treatment of invasive breast cancer: Quo Vadimus?

Breast cancer is a common malignancy among women. Despite an increase in incidence, breast cancer mortality has drastically dropped over the last 20 years. This change has been attributed to advances in screening, diagnosis, and treatment. This review summarises recent updates in the clinical approach to breast cancer. Advances in genetics have facilitated the stratification of the risk of recurrence in early-stage breast cancer. Advances in biology have led to the development of novel therapies (poly-ADP-ribose polymerase inhibitors, cyclin-dependent kinase 4/6 inhibitors, HER2 targeted agents). Their combination with endocrine (tamoxifen, aromatase inhibitors, GnRH-analogues, fulvestrant) and systematic therapy (anthracyclines, taxanes) in early and advanced disease have improved clinical outcomes. In the near future, neoadjuvant strategies in specific breast cancer subgroups (triple-negative breast cancers) and novel strategies (immune-modulatory agents) could further improve histopathological responses and survival. Radical mastectomies have been widely replaced by breast-conserving operations, while the traditional axillary dissection is being replaced with sentinel node techniques. Breast cancer therapeutics represents a great challenge due to patients' heterogeneous molecular and clinical characteristics, while the identification of reliable and easily reproducible predictive factors could further improve individualized treatment.

External Validation of the SERC Trial Population: Comparison with the Multicenter French Cohort, the Swedish and SENOMIC Trial Populations for Breast Cancer Patients with Sentinel Node Micro-Metastasis

Simple Summary

After the results of many trials, it is now accepted to omit axillary dissection in selected patients with limited axillary involvement. However, the external validity of these trials is questionable. Our study aimed to evaluate the accuracy of the real French population representativity in the SERC (Sentinelle Envahi et Randomisation du Curage) trial population for patients with breast cancer (BC) associated with sentinel node (SN) micro-metastasis and the differences between the studied population and the real French population. The secondary aim was to compare the French and the Swedish populations of patients with SN micro-metastasis. The findings of our study in addition to the previously demonstrated concordance between the SENOMIC (Sentinelle node Micrometastasis) trial and the Swedish National Breast Cancer Registry (NKBC) populations implied that the results of both the SERC and the SENOMIC trials can be applied to both the French and Swedish real populations.

Abstract

Many trials confirmed the safety of omitting axillary dissection in the selected patients treated for early breast cancer. The external validity of these trials is questionable. Our study aimed to evaluate the accuracy of the French population representativity in the SERC trial and the differences between these two populations as well as comparing the French and the Swedish populations (the SENOMIC trial population and the Swedish National Breast Cancer Registry (NKBC) cohort) of patients with sentinel node (SN) micro-metastasis. A higher rate of smaller tumors and grade 1 tumors was observed in the French cohort when compared to the SERC population. Our findings conclude that both French populations show similar characteristics. Positive non-sentinel node (NSN) rates at completion axillary lymph node dissection (ALND) were 10.28 % and 11.3 % in the SERC trial and French cohort, respectively (p = 0.5). The rate of grade 1 tumors was lower in the SENOMIC trial (16.2%) and in the NKBC cohort (17.4%) compared to the SERC trial population (27.3%) and the French cohort (34.4%). Our findings in addition to the previously demonstrated concordance between the SENOMIC trial and the NKBC populations imply that the results of both the SERC and the SENOMIC trials can be applied to both French and Swedish real populations.

Comparing Observation, Axillary Radiotherapy, and Completion Axillary Lymph Node Dissection for Management of Axilla in Breast Cancer in Patients with Positive Sentinel Nodes: A Systematic Review

PURPOSE

Several randomized controlled trials (RCTs) have investigated observation or axillary radiotherapy (ART) in place of completion axillary lymph node dissection (cALND) for management of positive sentinel nodes (SNs) in clinically node-negative women with breast cancer. The optimal treatment strategy for this population is not known.

METHODS

MEDLINE, Embase, and EBM Reviews-NHS Economic Evaluation Database were searched from inception until July 2019. A systematic review and narrative summary was performed of RCTs comparing observation or ART versus cALND in clinically node-negative female breast cancer patients with positive SNs. The Cochrane risk of bias tool for RCTs was used to assess risk of bias. Outcomes of interest included overall survival (OS), disease-free survival (DFS), axillary recurrence, and axillary surgery-related morbidity.

RESULTS

Three trials compared observation with cALND, and two trials compared ART with cALND. No studies blinded participants or personnel, and there was heterogeneity in inclusion criteria, study design, and follow-up. Neither observation nor ART resulted in statistically inferior 5- or 8-year OS or DFS compared with cALND. There was also no statistically significant increase in axillary recurrences associated with either approach. Four trials reported morbidity outcomes, and all showed cALND was associated with significantly more lymphedema, paresthesia, and shoulder dysfunction compared with observation or ART.

CONCLUSIONS

Women with clinically node-negative breast cancer and positive SNs can safely be managed without cALND.

NEONOD 2: Rationale and design of a multicenter non-inferiority trial to assess the effect of axillary surgery omission on the outcome of breast cancer patients presenting only micrometastasis in the sentinel lymph node after neoadjuvant chemotherapy

Sentinel lymph node biopsy alone, without complete axillary lymph node dissection, is the standard treatment of the axilla nodal chain in early-stage breast cancer patients presenting a negative sentinel lymph node. The updated results of the IBCSG 23-01 randomized trial recently provided evidence that this approach could be extended to early-stage breast cancer patients presenting only micrometastasis in the sentinel lymph node.

On the other hand, patients with large operable or locally advanced breast cancer and clinically positive lymph nodes currently receive neoadjuvant chemotherapy and sentinel lymph node biopsy, which is then followed by complete axillary node dissection if the sentinel lymph node till contains tumor residue, regardless of the extent of nodal disease. Assuming that patients presenting only a micrometastatic sentinel lymph node after neoadjuvant chemotherapy are clinically equivalent to the IBCSG 23-01 early-breast cancer patients with only micrometastatic sentinel node, then complete axillary dissection would be unneeded also in these subset of patients in the neoadjuvant setting. The multicenter uncontrolled non-inferiority trial NEONOD 2 we here present was designed to assess this hypothesis, i.e. whether or not omission of complete axillary nodal clearance worsens prognosis in patients with sentinel node resulting only micrometastatic after neoadjuvant chemotherapy.

Management of the axilla in patients with breast cancer and positive sentinel lymph node biopsy: An evidence-based update in a European breast center

The surgical approach to the axilla in breast cancer has been a controversial issue for more than three decades. Data from recently published trials have provided practice-changing recommendations in this scenario. However, further controversies have been triggered in the surgical community, resulting in heterogeneous diffusion of these recommendations. The development of clinical guidelines for the management of the axilla in patients with breast cancer is a work in progress. A multidisciplinary team discussion was held at the research hospital Policlinico San Matteo from the Università degli Studi di Pavia with the aim to update recommendations for the management of the axilla in patients with breast cancer. An evidence-based approach is presented. Our multidisciplinary panel determined that axillary dissection after a positive sentinel lymph node biopsy may be avoided in cN0 patients with micro/macrometastasis to ≤2 sentinel nodes, with age ≥40y, lesions ≤3 cm, who have not received neoadjuvant chemotherapy and have planned breast conservation (BCS) with whole breast radiotherapy (WBRT). Cases with gross (>2 mm) ECE in SLNs are evaluated on individual basis for completion ALND, axillary radiotherapy or omission of both. Patients fulfilling the criteria listed above who undergo mastectomy, may also avoid axillary dissection after multidisciplinary discussion of individual cases for consideration of axillary irradiation. Women 70 years or older with hormone receptors positive invasive lesions ≤3 cm, clinically negative nodes, and serious or multiple comorbidities who undergo BCS with WBRT, may forgo axillary staging/surgery (if mastectomy or larger tumor, comorbidities and life expectancy are taken into account).

Can Preoperative Ultrasonography and MRI Replace Sentinel Lymph Node Biopsy in Management of Axilla in Early Breast Cancer-a Prospective Study from a Tertiary Cancer Center

Although SLNB is a less invasive procedure in detecting axillary lymph node metastases(ALNM) in early breast cancer; still, it carries some complications like lymphedema and in addition, performing SLNB requires surgical skills, technical knowledge, presence of facility like preoperative sentinel lymphoscintigraphy, and availability of hand-held gamma probe for intraoperative assessment. We calculated the relative diagnostic strength of preoperative axillary USG and MRI and compared with of SLNB for detection of ALNM in early breast cancer and assessed whether MRI and USG could accurately predict axillary LN status, potentially replacing SLNB. We evaluated 40 cases of clinically node-negative early breast cancer with preoperative axillary USG and MRI and subsequently subjected to SLNB. The sensitivity, specificity, PPV, NPV, and accuracy of axillary USG were 62.5%, 96.88%, 88.33%, 91.18%, and 90% respectively (p value < 0.001). The sensitivity, specificity, PPV, NPV, and accuracy of MRI in detection of ALNM were 75%, 93.75%, 75%, 93.75%, and 90% (p value < 0.001). The sensitivity, specificity, PPV, NPV, and accuracy of combined USG and MRI in detection of ALNM were 87.5%,90.63%, 70%, 96.67%, and 90% respectively (p value < 0.001), which are comparable to previous study series. The diagnostic performance of combined approach of axillary USG and MRI is promising, as the NPV of combined USG and MRI is approaching the NPV of the SLNB in detecting ALNM. Based on above findings, if axillary LNs are found nonsuspicious in preoperative axillary USG and MRI, further axillary dissection may be avoided, and if found suspicious, then ALND may be directly proceeded avoiding SLNB in between.

Trends in axillary lymph node dissection for early-stage breast cancer in Europe: Impact of evidence on practice

BACKGROUND

Data from recently published trials have provided practice-changing recommendations for the surgical approach to the axilla in breast cancer. Patients with T1-2 lesions, treated with breast conservation, who have not received neoadjuvant chemotherapy and have 1-2 positive sentinel nodes (Z0011-criteria) may avoid axillary lymph node dissection (ALND). We aim to describe the dissemination of this practice in Europe over an extended period of time.

METHODS

Our source of data was the eusomaDB, a central data warehouse of prospectively collected information of the European Society of Breast Cancer Specialists (EUSOMA). We identified cases fulfilling Z0011-criteria from 2005 to 2016 from 34 European breast centers and report trends in ALND. Data derived from Germany, Italy, Belgium, Switzerland, Austria, and Netherlands.

RESULTS

6671 patients fulfilled Z0011-criteria. Rates of ALND showed a statistically significant decrease from 2010 (89%) to 2011 (73%), reaching 46% in 2016 (p < 0.001). After multivariable analysis, factors associated with higher probability of ALND were earlier year of surgery, younger age, increasing tumor size and grade, and being operated in Italy (p < 0.001). The minimum and maximal rates of ALND in the most recent two-year period (2015-2016) were 0% and 83% in two centers located in different countries (p < 0.001).

CONCLUSION

Our study demonstrates, a decrease in rates of ALND that started after year 2010 through the end of the study period. Wide differences were observed among centers and countries indicating the need to spread unified clinical guidelines in Europe to allow for homogeneous evidence-based practice patterns.

Overview of the pathological results and treatment characteristics in the first 1000 patients randomized in the SERC trial: axillary dissection versus no axillary dissection in patients with involved sentinel node

Background

Three randomized trials have concluded at non inferiority of omission of complementary axillary lymph node dissection (cALND) for patients with involved sentinel node (SN). However, we can outline strong limitations of these trials to validate this attitude with a high scientific level. We designed the SERC randomized trial (ClinicalTrials.gov, number NCT01717131) to compare outcomes in patients with SN involvement treated with ALND or no further axillary treatment. The aim of this study was to analyze results of the first 1000 patients included.

Methods

SERC trial is a multicenter non-inferiority phase 3 trial. Multivariate logistic regression analysis was used to identify independent factors associated with adjuvant chemotherapy administration and non-sentinel node (NSN) involvement.

Results

Of the 963 patients included in the analysis set, 478 were randomized to receive cALND and 485 SLNB alone. All patient demographics and tumor characteristics were balanced between the two arms. SN ITC was present in 6.3% patients (57/903), micro metastases in 33.0% (298), macro metastases in 60.7% (548) and 289 (34.2%) were non eligible to Z0011 trial criteria.

Whole breast or chest wall irradiation was delivered in 95.9% (896/934) of patients, adjuvant chemotherapy in 69.5% (644/926), endocrine therapy in 89.6% (673/751) and the proportions were similar in the two arms. The overall rate of positive NSN was 19% (84/442) for patients with cALND. Crude rates of positive NSN according to SN status were 4.5% for ITC (1/22), 9.5% for micro metastases (13/137), 23.9% for macro metastases (61/255) and were respectively 29.36% (64/218), 9.33% (7/75) and 7.94% (10/126) when chemotherapy was administered after cALND, before cALND and for patients without chemotherapy.

Conclusion

The main objective of SERC trial is to demonstrate non inferiority of cALND omission. A strong interaction between timing of cALND and chemotherapy with positive NSN rate was observed.

Trial registration

This study is registered with ClinicalTrials.gov, number NCT01717131 October 19, 2012.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-5053-7) contains supplementary material, which is available to authorized users.

What Is the Best Management of cN0pN1(sn) Breast Cancer Patients?

Although the majority of breast cancer patients are clinically node-negative (cN0) at diagnosis, 15-20% will have a metastatic sentinel lymph node (SLN, pN1(sn)). While a less radical approach regarding axillary surgery in cN0 patients with a positive SLN biopsy is advocated, the limitations of 5 published trials on axillary management in pN1(sn) are discussed intensely in the literature and support the performance of ongoing validation and extension trials, especially considering the lack of data in the setting of mastectomy. As locoregional radiotherapy has a significant effect on both recurrence and survival, a standardization of locoregional radiotherapy in the situation of SLN biopsy alone in pN1(sn) patients has to be defined in the future, and de-escalation trials should embrace a truly multidisciplinary approach. This is also of utmost importance considering the fact that high-volume nodal disease requires an intensified adjuvant chemotherapy strategy to which patients omitting axillary dissection cannot be stratified. Finally, there is mounting evidence that the therapeutic role of extensive axillary surgery in low-volume nodal disease is negligible, and multidisciplinary and translational efforts must be undertaken to individualize treatment in order to gain a reasonable balance between necessary staging information and unnecessary treatment-related morbidity.

Reducing harms from treatment. Sixteen years of surgery of the axilla for screen-detected breast cancers in Italy

OBJECTIVES

Available evidence on axillary surgery has accumulated dramatically in the last two decades in favor of less invasive care. The aim of this paper is to study 16-years trends in the surgical management of the axilla in a large population-based data set of screen-detected breast cancers in Italy and to document at what extent recommendations have been adopted in actual clinical care.

MATERIAL AND METHODS

This is a retrospective cohort study documenting the surgical management of the axilla in primary breast cancer patients over time. We retrieved from the Italian database of screen-detected cancers 41213 cases diagnosed in women aged 50-69 between years 2000 and 2015 in twelve Italian Regions.

RESULTS

In pN0 cases, an increasing trend (p < 0.001) in the number of patients who received sentinel lymph node biopsy (SLNB) as the only axillary staging procedure was observed. In pN + cases SLNB was the only staging procedure in an increasing number of patients (p < 0.001) especially since the publication of the ACOSOG-Z0011 paper. In ductal carcinoma in situ (DCIS) SLNB was more frequent in mastectomies and in high grade and large lesions. However, 45% of low grade, small DCIS over the whole time period had some form of axillary surgery.

CONCLUSION

This large series of screen-detected cases documents a strong time trend in the direction of reducing axillary surgery and hence potential harms from treatment. The continuing practice of SLNB in low risk DCIS is of concern in an era of increasing awareness towards overdiagnosis and overtreatment.

Restricted Axillary Staging in Clinically and Sonographically Node-Negative Early Invasive Breast Cancer (c/iT1-2) in the Context of Breast Conserving Therapy: First Results Following Commencement of the Intergroup-Sentinel-Mamma (INSEMA) Trial

Axillary lymph node status remains an important prognostic factor in early breast cancer. It is regarded as an indicator for (neo)adjuvant systemic treatment and postoperative radiotherapy of the regional lymphatics. Commenced in September 2015, the INSEMA trial is investigating whether operative determination of nodal status as part of breast conserving therapy (BCT) for early stage breast cancer (c/iT1-2 c/iN0) can be avoided without reducing oncological safety. After inclusion of 1001 patients there was general acceptance of the complex study design by patients and study doctors so that recruitment for the first randomisation (axillary sentinel lymph node biopsy [SLNB]: yes or no) achieved predicted case numbers. The second randomisation however (SLNB alone versus complete axillary dissection when one or two macrometastases are present at SLNB) recruited fewer cases than expected for the following three reasons: a) the 13 % rate of one or two macrometastases after SLNB in the INSEMA trial collective was lower than expected; b) around 20 % of patients refused the second randomisation; c) there was delayed inclusion of the Austrian study centres, which only recruited for the second randomisation. Lack of knowledge of nodal status when SLNB is avoided represents a new challenge for the postoperative tumour board. In particular decisions on chemotherapy for luminal-like tumours and irradiation of the lymphatics (excluding axilla) must be guided by tumour biological parameters. The INSEMA trial does not provide answers to some important questions, e.g. it remains unclear whether patients without SLNB can be offered partial breast irradiation alone in low-risk situations and whether SLNB can also be avoided in patients with stage T1-2 tumours who have a mastectomy indication.