Impact of Imaging-Guided Localization on Performance of Tailored Axillary Surgery in Patients with Clinically Node-Positive Breast Cancer: Prospective Cohort Study Within TAXIS (OPBC-03, SAKK 23/16, IBCSG 57-18, ABCSG-53, GBG 101)

BACKGROUND

Tailored axillary surgery (TAS) is a novel surgical concept for clinical node-positive breast cancer. It consists of the removal of the sentinel lymph nodes (LNs), as well as palpably suspicious nodes. The TAS technique can be utilized in both the upfront and neoadjuvant chemotherapy (NACT) setting. This study assessed whether/how imaging-guided localization (IGL) influenced TAS.

PATIENTS AND METHODS

This was a prospective observational cohort study preplanned in the randomized phase-III OPBC-03/TAXIS trial. IGL was performed at the surgeon's discretion for targeted removal of LNs during TAS. Immediate back-up axillary lymph node dissection (ALND) followed TAS according to TAXIS randomization.

RESULTS

Five-hundred patients were included from 44 breast centers in six countries, 151 (30.2%) of whom underwent NACT. IGL was performed in 84.4% of all patients, with significant variation by country (77.6-100%, p < 0.001). No difference in the median number of removed (5 vs. 4, p = 0.3) and positive (2 vs. 2, p = 0.6) LNs by use of IGL was noted. The number of LNs removed during TAS with IGL remained stable over time (p = 0.8), but decreased significantly without IGL, from six (IQR 4-6) in 2019 to four (IQR 3-4) in 2022 (p = 0.015). An ALND was performed in 249 patients, removing another 12 (IQR 9-17) LNs, in which a median number of 1 (IQR 0-4) was positive. There was no significant difference in residual nodal disease after TAS with or without IGL (68.0% vs. 57.6%, p = 0.2).

CONCLUSIONS

IGL did not significantly change either the performance of TAS or the volume of residual nodal tumor burden.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03513614.

Every Tube Counts: reducing extra tubes drawn in the emergency department

A common practice exists in hospitals where extra tubes of blood are collected for possible add-on testing, this practice contributes to wastage of consumables. Baseline estimates from a 5-month local lab information system audit revealed that ~65 extra tubes per day were being collected, with an additional 2-week manual audit of all extra tubes received in the laboratory confirming the practice. The audits showed that the majority of the tubes (~99%) were being drawn from the adult emergency department (ED). Furthermore, only 5% of the extra tubes were being used for add-on testing, whereas the remaining tubes had no testing performed on them and were discarded at the end of the day. This translates to over 23 000 extra tubes being wasted annually.After initial discussion with ED leadership, the practice was identified as primarily nurse driven. An educational intervention was created and entitled 'Every Tube Counts', with the aim to reduce extra tube collections in the adult ED by 50% within the first month of intervention. First, a memo with initial findings and a request to stop the practice of extra tube collection was sent out to all ED staff. After 2 weeks of additional data collection, it was noticed that extra tubes were still being collected. A second intervention, which consisted of another communication and utilisation of nurse educators to disseminate the information to nursing staff, saw a remarkable ~80% reduction in collection of extra tubes in the following few months after the second intervention. The practice was followed for an additional 15 months, which saw a slight increase of extra tube collections over time with a levelling off towards the latter period of the study. However, the target goal was maintained over the entire study period.

Association of Axillary Dissection With Systemic Therapy in Patients With Clinically Node-Positive Breast Cancer

Importance

The role of axillary lymph node dissection (ALND) to determine nodal burden to inform systemic therapy recommendations in patients with clinically node (cN)-positive breast cancer (BC) is currently unknown.

Objective

To address the association of ALND with systemic therapy in cN-positive BC in the upfront surgery setting and after neoadjuvant chemotherapy (NACT).

Design, Setting, and Participants

This was a prospective, observational, cohort study conducted from August 2018 to June 2022. This was a preplanned study within the phase 3 randomized clinical OPBC-03/TAXIS trial. Included were patients with confirmed cN-positive BC from 44 private, public, and academic breast centers in 6 European countries. After NACT, residual nodal disease was mandatory, and a minimum follow-up of 2 months was required.

Exposures

All patients underwent tailored axillary surgery (TAS) followed by ALND or axillary radiotherapy (ART) according to TAXIS randomization. TAS removed suspicious palpable and sentinel nodes, whereas imaging-guidance was optional. Systemic therapy recommendations were at the discretion of the local investigators.

Results

A total of 500 patients (median [IQR] age, 57 [48-69] years; 487 female [97.4%]) were included in the study. In the upfront surgery setting, 296 of 335 patients (88.4%) had hormone receptor (HR)-positive and Erb-B2 receptor tyrosine kinase 2 (ERBB2; formerly HER2 or HER2/neu)-negative disease: 145 (49.0%) underwent ART, and 151 (51.0%) underwent ALND. The median (IQR) number of removed positive lymph nodes without ALND was 3 (1-4) nodes compared with 4 (2-9) nodes with ALND. There was no association of ALND with the proportion of patients undergoing adjuvant chemotherapy (81 of 145 [55.9%] vs 91 of 151 [60.3%]; adjusted odds ratio [aOR], 0.72; 95% CI, 0.19-2.67) and type of systemic therapy. Of 151 patients with NACT, 74 (51.0%) underwent ART, and 77 (49.0%) underwent ALND. The ratio of removed to positive nodes was a median (IQR) of 4 (3-7) nodes to 2 (1-3) nodes and 15 (12-19) nodes to 2 (1-5) nodes in the ART and ALND groups, respectively. There was no observed association of ALND with the proportion of patients undergoing postneoadjuvant systemic therapy (57 of 74 [77.0%] vs 55 of 77 [71.4%]; aOR, 0.86; 95% CI, 0.43-1.70), type of postneoadjuvant chemotherapy (eg, capecitabine: 10 of 74 [13.5%] vs 10 of 77 [13.0%]; trastuzumab emtansine-DM1: 9 of 74 [12.2%] vs 11 of 77 [14.3%]), or endocrine therapy (eg, aromatase inhibitors: 41 of 74 [55.4%] vs 36 of 77 [46.8%]; tamoxifen: 8 of 74 [10.8%] vs 6 of 77 [7.8%]).

Conclusion

Results of this cohort study suggest that patients without ALND were significantly understaged. However, ALND did not inform systemic therapy recommendations.

Trends in use of neoadjuvant systemic therapy in patients with clinically node-positive breast cancer in Europe: prospective TAXIS study (OPBC-03, SAKK 23/16, IBCSG 57-18, ABCSG-53, GBG 101)

PURPOSE

The aim of this study was to evaluate clinical practice heterogeneity in use of neoadjuvant systemic therapy (NST) for patients with clinically node-positive breast cancer in Europe.

METHODS

The study was preplanned in the international multicenter phase-III OPBC-03/TAXIS trial (ClinicalTrials.gov Identifier: NCT03513614) to include the first 500 randomized patients with confirmed nodal disease at the time of surgery. The TAXIS study's pragmatic design allowed both the neoadjuvant and adjuvant setting according to the preferences of the local investigators who were encouraged to register eligible patients consecutively.

RESULTS

A total of 500 patients were included at 44 breast centers in six European countries from August 2018 to June 2022, 165 (33%) of whom underwent NST. Median age was 57 years (interquartile range [IQR], 48-69). Most patients were postmenopausal (68.4%) with grade 2 and 3 hormonal receptor-positive and human epidermal growth factor receptor 2-negative breast cancer with a median tumor size of 28 mm (IQR 20-40). The use of NST varied significantly across the countries (p < 0.001). Austria (55.2%) and Switzerland (35.8%) had the highest percentage of patients undergoing NST and Hungary (18.2%) the lowest. The administration of NST increased significantly over the years (OR 1.42; p < 0.001) and more than doubled from 20 to 46.7% between 2018 and 2022.

CONCLUSION

Substantial heterogeneity in the use of NST with HR+/HER2-breast cancer exists in Europe. While stringent guidelines are available for its use in triple-negative and HER2+ breast cancer, there is a need for the development of and adherence to well-defined recommendations for HR+/HER2-breast cancer.

The Lucerne Toolbox 2 to optimise axillary management for early breast cancer: a multidisciplinary expert consensus

Clinical axillary lymph node management in early breast cancer has evolved from being merely an aspect of surgical management and now includes the entire multidisciplinary team. The second edition of the "Lucerne Toolbox", a multidisciplinary consortium of European cancer societies and patient representatives, addresses the challenges of clinical axillary lymph node management, from diagnosis to local therapy of the axilla. Five working packages were developed, following the patients' journey and addressing specific clinical scenarios. Panellists voted on 72 statements, reaching consensus (agreement of 75% or more) in 52.8%, majority (51%-74% agreement) in 43.1%, and no decision in 4.2%. Based on the votes, targeted imaging and standardized pathology of lymph nodes should be a prerequisite to planning local and systemic therapy, axillary lymph node dissection can be replaced by sentinel lymph node biopsy ( ± targeted approaches) in a majority of scenarios; and positive patient outcomes should be driven by both low recurrence risks and low rates of lymphoedema.

Establishing quality indicators for point of care glucose testing: recommendations from the Canadian Society for Clinical Chemists Point of Care Testing and Quality Indicators Special Interest Groups

OBJECTIVES

Monitoring quality indicators (QIs) is an important part of laboratory quality assurance (QA). Here, the Canadian Society of Clinical Chemists (CSCC) Point of Care Testing (POCT) and QI Special Interest Groups describe a process for establishing and monitoring QIs for POCT glucose testing.

METHODS

Key, error prone steps in the POCT glucose testing process were collaboratively mapped out, followed by risk assessment for each step. Steps with the highest risk and ability to detect a non-conformance were chosen for follow-up. These were positive patient identification (PPID) and repeat of critically high glucose measurements. Participating sites were asked to submit aggregate data for these indicators from their site(s) for a one-month period. The PPID QI was also included as part of a national QI monitoring program for which fifty-seven sites submitted data.

RESULTS

The percentage of POCT glucose tests performed without valid PPID ranged from 0-87%. Sites without Admission-Discharge-Transfer (ADT) connectivity to POCT meters were among those with the highest percentage of POCT glucose tests performed without valid PPID. The percentage repeated critically high glucose measurements ranged from 0-50%, indicating low compliance with this recommendation. A high rate of discordance was also noted when critically high POCT glucose measurements were repeated, demonstrating the importance of repeat testing prior to insulin administration.

CONCLUSIONS

Here, a process for establishing these QIs is described, with preliminary data for two QIs chosen from this process. The findings demonstrate the importance of QIs for identification and comparative performance monitoring of non-conformances to improve POCT quality.

Uncertainties and controversies in axillary management of patients with breast cancer

The aims of this Oncoplastic Breast Consortium and European Breast Cancer Research Association of Surgical Trialists initiative were to identify uncertainties and controversies in axillary management of early breast cancer and to recommend appropriate strategies to address them. By use of Delphi methods, 15 questions were prioritized by more than 250 breast surgeons, patient advocates and radiation oncologists from 60 countries. Subsequently, a global virtual consensus panel considered available data, ongoing studies and resource utilization. It agreed that research should no longer be prioritized for standardization of axillary imaging, de-escalation of axillary surgery in node-positive cancer and risk evaluation of modern surgery and radiotherapy. Instead, expert consensus recommendations for clinical practice should be based on current evidence and updated once results from ongoing studies become available. Research on de-escalation of radiotherapy and identification of the most relevant endpoints in axillary management should encompass a meta-analysis to identify knowledge gaps, followed by a Delphi process to prioritize and a consensus conference to refine recommendations for specific trial designs. Finally, treatment of residual nodal disease after surgery was recommended to be assessed in a prospective register.

Tailored axillary surgery - A novel concept for clinically node positive breast cancer

Axillary surgery in patients with breast cancer has been a history of de-escalation; however, surgery for clinically node-positive breast cancer remained at the dogmatic level of axillary lymph node dissection (ALND). In these patients, currently the only way to avoid ALND is neoadjuvant systemic treatment (NST) with nodal pathologic complete response (pCR) as diagnosed by selective lymph node removal. However, pCR rates are highly dependent on tumor biology, with luminal tumors being most present yet showing the lowest pCR rates. Therefore, the TAXIS trial is investigating whether in clinically node-positive patients, either with residual disease after NST or in the upfront surgical setting, ALND can be safely omitted. All patients undergo tailored axillary surgery (TAS), which includes removal of the biopsied and clipped node, the sentinel lymph nodes as well as all palpably suspicious nodes, turning a clinically positive axilla into a clinically negative. Feasibility of TAS was recently confirmed in the first pre-specified TAXIS substudy. TAS is followed by axillary radiotherapy to treat any remaining nodal disease. Disease-free survival is the primary endpoint of this non-inferiority trial, and morbidity as well as quality of life are the main secondary endpoints, with ALND being known for having a relevant negative impact on both. Currently, 663 of 1500 patients were randomized; accrual completion is projected for 2025. The TAXIS trial stands out in including clinically node-positive patients in both the neoadjuvant and upfront surgery setting, thereby investigating surgical de-escalation at the far-end of the risk spectrum of patients with breast cancer.

Abstract P3-05-49: Number of involved organs at baseline is prognostic for overall survival in patients with metastatic breast cancer: Results from the AGMT_MBC-Registry

Background: Hormone-receptor (HR) status, HER2 Status, de novo metastatic disease, distant recurrence-free interval (DRFI), and visceral disease are known prognostic factors in metastatic breast cancer (MBC). Therefore, in the majority of clinical trials, randomization is stratified for these parameters. Whether the number of involved organs at baseline has an additional prognostic value was examined in this analysis.

Patients and methods: The AGMT-MBC-Registry is a multicenter nationwide ongoing retrospective and prospective registry for MBC patients in Austria. In this analysis, patients with known HR status, HER2 status, and available survival data were included. Multivariable hazard ratios were estimated by COX proportional hazard models. For variable selection a backward stepwise model selection using the Akaike information criterion was performed.

Results: As of 04/05/2022, 2,235 patients have been included in the registry, of which 1,840 patients fulfilled the inclusion criteria. In two different multivariable COX proportional hazard models for overall survival, the number of involved organs was a highly statistically significant independent prognostic factor: (1) a model including the number of involved organs at baseline together with known prognostic factors (see Table 1); (2) a stepwise selection model additionally including menopausal status and involved metastatic organ sites (bone, liver, lung, brain, and lymph nodes) separately. This effect was maintained in sensitivity analysis taking different breast cancer subtypes as well as visceral and non-visceral disease into account.

Conclusion: The number of involved organs at baseline is an independent prognostic factor in MBC and should be considered as a stratification factor in randomized trials.

Table 1. Multivariable Model for overall survival.

Citation Format: Gabriel Rinnerthaler, Simon P. Gampenrieder, Christoph Tinchon, Andreas Petzer, Marija Balic, Sonja Heibl, Margit Sandholzer, August F. Zabernigg, Daniel Egle, Christopher Hager, Petra Pichler, Florian Roitner, Johannes Andel, Kathrin Strasser-Weippl, Michael Knauer, Michael Hubalek, Christian F. Singer, Richard Greil. Number of involved organs at baseline is prognostic for overall survival in patients with metastatic breast cancer: Results from the AGMT_MBC-Registry [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P3-05-49.

Abstract P2-14-08: Trends in neoadjuvant systemic therapy rates in Europe: Pre-planned substudy of TAXIS (OPBC-03, SAKK 23/16, IBCSG 57-18, ABCSG-53, GBG 101)

Introduction: Even though randomized controlled trials could not show a significant survival benefit for the use of neoadjuvant systemic therapy (NST), it is increasingly recommended for patients with clinically node-positive breast cancer due to its implications on prognosis, locoregional downstaging and response-driven adjuvant systemic therapy. The aim of this study was to assess the need for international standardization of treatment recommendations by evaluating clinical practice heterogeneity in use of NST for patients with clinically node-positive breast cancer in Europe. Methods: The study was preplanned in the international multicenter phase-III OPBC-03/TAXIS trial (ClinicalTrials.gov Identifier: NCT03513614) after randomization of the first 500 patients with clinically node-positive breast cancer who underwent axillary lymph node dissection (ALND) or axillary radiation (ART) without ALND after tailored axillary surgery (TAS) in the context of extended regional nodal irradiation. Clinically node-positive breast cancer was defined by confirmed nodal disease at the time of initial diagnosis; in case of neoadjuvant therapy, residual nodal disease was mandatory. Investigators were encouraged to enroll all eligible patients consecutively. However, TAXIS is unique inasmuch as its pragmatic design allows both the neoadjuvant and adjuvant setting according to the preferences of the treating physicians and institutions and thus provides an excellent opportunity to study patterns and trends in use of NST in patients with clinically positive nodes in Europe. Results: A total of 500 patients with a median age of 57 years (IQR: 48-69 years) were included at 44 breast centers in 6 European countries from August 2018 to June 2022. Subtype was hormone receptor (HR) positive (+) and human epidermal growth factor receptor 2 (HER2) negative (-) in 393 (80.0%), HR+/HER2+ in 52 (10.6%), HR-/HER2+ in 5 (1.0%) and HR-/HER2- in 34 (6.9%) patients. The rate of patients undergoing NST was 31.4% with a significant upward trend over time during the study period (from 20.0% in 2018 to 38.1% in 2022; p=0.044). The use of NST varied significantly by country (p=&lt; 0.001) and by site (p=0.015). For patients with clinical AJCC tumor stage II and III, the rates of patients undergoing NST in Switzerland were 26.5% (18 of 68) and 35.9% (92 of 256), in Germany 22.2% (2 of 9) and 30.4% (7 of 23), in Austria 50% (7 of 14) and 60% (9 of 15) and in Hungary 0% (0 of 15) and 20.7% (18 of 87), respectively (p=0.019 and 0.004). Large differences by country were found for ER+/HER2- breast cancer, ranging from 13.1% (11 of 84) in Hungary to 47.8% (11 of 23) in Austria (p=0.007). Within Switzerland, which was the country with most included patients (328 of 500) and participating sites (n=25), the rate of patients undergoing NST for ER+/HER2- breast cancer varied considerably by site, ranging from 10% (2 of 20) to 50% (11 of 22). Discussion: This study revealed substantial heterogeneity in clinical practice in Europe, indicating the need for development of and adherence to consistent guidelines to standardize the international use of NST.

Citation Format: Walter P. Weber, Zoltan Matrai, Stefanie Hayoz, Guido Henke, Daniel R. Zwahlen, Günther Gruber, Frank Zimmermann, Thomas Ruhstaller, Simone Muenst, Markus Ackerknecht, Christian Kurzeder, Sherko Küemmel, Vesna Bjelic-Radisic, Viktor Smanykó, Conny Vrieling, Rok Satler, Inna Meyer, Charles Becciolini, Susanne Bucher, Colin Simonson, Peter M. Fehr, Natalie Gabriel, Robert Maráz, Dimitri Sarlos, Konstantin J. Dedes, Cornelia Leo, Gilles Berclaz, Hisham Fansa, Christopher Hager, Klaus Reisenberger, Ákos Sávolt, Christian F. Singer, Roland Reitsamer, Jelena Winkler, Giang Thanh Lam Lam, Mathias K. Fehr, Tatiana Naydina, Magdalena Kohlik, Karine Clerc, Valerijus Ostapenko, Florian Fitzal, Martin Heidinger, Nadia Maggi, Alexandra Schulz, Pagona Markellou, Loïc Lelièvre, Daniel Egle, Jörg Heil, Michael Knauer, Christoph Tausch. Trends in neoadjuvant systemic therapy rates in Europe: Pre-planned substudy of TAXIS (OPBC-03, SAKK 23/16, IBCSG 57-18, ABCSG-53, GBG 101) [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P2-14-08.

Abstract P4-01-27: Prognosis and treatment landscape of HER2-positive metastatic breast cancer (MBC) before the availability of tucatinib and trastuzumab-deruxtecan: Results from the Austrian AGMT_MBC-Registry

Background: New anti-HER2 drugs such as tucatinib and trastuzumab deruxtecan (T-DXd) have shown to improve survival of HER2+ MBC in clinical phase III trials. To allow a future confirmation of this survival advantage in real world, we evaluated the prognosis of HER2+ MBC patients before the availability of tucatinib and T-DXd in Austria. Furthermore, we analyzed the treatment landscape and the drop-out rate between subsequent lines of therapy as documented in the MBC-Registry of the Austrian Study Group of Medical Tumor Therapy (AGMT).

Patients and methods: The AGMT-MBC-Registry is a multicenter nationwide ongoing retrospective and prospective registry for MBC patients in Austria. In this analysis, patients with known HER2 status, available survival data, at least one treatment line and diagnosis of metastatic disease after 01/04/2013 (pertuzumab available) were included. Follow-up was censored at Dec 31, 2020, when tucatinib und T-DXd became available.

Results: As of 04/05/2022, 2,235 patients have been included in the registry. Out of 2,000 evaluable patients, 362 (18.1%) were HER2+, of which 171 (47.2%) fulfilled the inclusion criteria. Out of them 69.0% were hormone-receptor positive. In patients with metachronous metastatic disease (53.2%), 61.5% had received trastuzumab-based treatment for early breast cancer. Median overall survival (OS) for all patients was 50.1 months (95%CI 40.7-73.0), and 66.1 months (95%CI 50.1-NA) for those who received a pertuzumab combination as first-line treatment. The drop-out rate from 1st- to 5th-line was 26.9%, 24.4%, 28.3% and 36.7%, respectively. This yields an estimated percentage of patients that received at least 3, 4, and 5 treatment lines for advanced disease of 55.2%, 39.6% and 25.1%, respectively. In first line, 50.9% received trastuzumab plus pertuzumab and 11.1% T- DM1. In second line, 38.9% were treated with T-DM1 and 35.6% with trastuzumab-based chemotherapy or endocrine therapy. In third line, 11.3%, 17.0% and 49.1% received T-DM1, lapatinib-based and trastuzumab-based therapy, respectively. Outcomes according to treatment line are shown in Table 1.

Conclusion: Median overall survival of HER2+ MBC in Austria who received a pertuzumab combination treatment is comparable to the results reported in the registration CLEOPATRA trial. In this analysis, only ~40% of patients are estimated to receive more than three treatment lines and treatment benefit diminished from line to line. This underlines the importance of investigating and ultimately using the most effective compounds in early treatment lines in order to allow more patients to benefit from these life prolonging drugs.

Table 1: Outcome according to treatment line

Citation Format: Simon P. Gampenrieder, Gabriel Rinnerthaler, Christoph Tinchon, Andreas Petzer, Marija Balic, Sonja Heibl, Margit Sandholzer, August F. Zabernigg, Daniel Egle, Christopher Hager, Petra Pichler, Florian Roitner, Johannes Andel, Kathrin Strasser-Weippl, Michael Knauer, Michael Hubalek, Christian F. Singer, Richard Greil. Prognosis and treatment landscape of HER2-positive metastatic breast cancer (MBC) before the availability of tucatinib and trastuzumab-deruxtecan: Results from the Austrian AGMT_MBC-Registry [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P4-01-27.

Patient-reported outcomes for the Intergroup Sentinel Mamma study (INSEMA): A randomised trial with persistent impact of axillary surgery on arm and breast symptoms in patients with early breast cancer

BACKGROUND

In clinically node-negative breast cancer patients, the INSEMA trial (NCT02466737) assessed the non-inferiority of avoiding sentinel lymph node biopsy (SLNB) or axillary lymph node dissection (ALND). Here we present patient-reported outcomes (PROs) as a secondary endpoint.

METHODS

PROs were assessed for patients with no axillary surgery, SLNB alone, and ALND. Quality of life (QoL) questionnaire EORTC QLQ-C30 and its breast cancer module (BR23) were used at baseline (pre-surgery) and 1, 3, 6, 12, and 18 months after surgery. The QoL scores were compared using repeated measures mixed models based on the safety set.

FINDINGS

Between 2015 and 2019, 5502 patients were recruited for the first randomization, and 5154 were included in the intent-to-treat set (4124 SLNB versus 1030 no SLNB). In the case of one to three macrometastases after SLNB, 485 patients underwent second randomization (242 SLNB alone versus 243 ALND). Questionnaire completion response remained high throughout the trial: over 70% at all time points for the first randomization. There were significant differences for the BRBS (breast symptoms) and BRAS (arm symptoms) scores favoring the no SLNB group in all post-baseline assessments. Patients in the SLNB group showed significantly and clinically relevant higher scores for BRAS (differences in mean values ≥5.0 points at all times), including pain, arm swelling, and impaired mobility in all postoperative visits, with the highest difference at one month after surgery. Scoring of the QLQ-C30 questionnaire revealed no relevant differences between the treatment groups, although some comparisons were statistically significant.

INTERPRETATION

This is one of the first randomized trials investigating the omission of SLNB in clinically node-negative patients and the first to report comprehensive QoL data. Patients with no SLNB benefitted regarding arm symptoms/functioning, while no relevant differences in other scales were seen.

FUNDING

Supported by German Cancer Aid (Deutsche Krebshilfe, Bonn, Germany), Grant No. 110580 and Grant No. 70110580 to University Medicine Rostock.

Ovarian Function Suppression: A Deeper Consideration of the Role in Early Breast Cancer and its Potential Impact on Patient Outcomes: A Consensus Statement from an International Expert Panel

It has been suggested that the benefit of adjuvant chemotherapy (CT) in premenopausal women with hormone receptor-positive (HR+), human epidermal growth factor receptor 2 negative (HER2-) early breast cancer may be related, at least in part, to CT-induced ovarian function suppression (OFS) in this subgroup of patients. Although this hypothesis has not been directly tested in large randomized clinical trials, the observations from prospective studies have been remarkably consistent in showing a late benefit of CT among the subgroup of patients who benefit (ie, women who were close to menopause). The hypothesis has important clinical implications, as it may be possible to spare the associated adverse effects of adjuvant CT in a select group of women with early breast cancer, in favor of optimizing OFS and endocrine therapy (ET), without compromising clinical outcomes. Such an approach has the added benefit of preserving the key quality of life outcomes in premenopausal women, particularly by preventing the irreversible loss of ovarian function that may result from CT use. For this reason, we convened an international panel of clinical experts in breast cancer treatment to discuss the key aspects of the available data in this area, as well as the potential clinical implications for patients. This article summarizes the results of these discussions and presents the consensus opinion of the panel regarding optimizing the use of OFS for premenopausal women with HR+, HER2- early breast cancer.

Oncoplastic breast consortium recommendations for mastectomy and whole breast reconstruction in the setting of post-mastectomy radiation therapy

Aim

Demand for nipple- and skin- sparing mastectomy (NSM/SSM) with immediate breast reconstruction (BR) has increased at the same time as indications for post-mastectomy radiation therapy (PMRT) have broadened. The aim of the Oncoplastic Breast Consortium initiative was to address relevant questions arising with this clinically challenging scenario.

Methods

A large global panel of oncologic, oncoplastic and reconstructive breast surgeons, patient advocates and radiation oncologists developed recommendations for clinical practice in an iterative process based on the principles of Delphi methodology.

Results

The panel agreed that surgical technique for NSM/SSM should not be formally modified when PMRT is planned with preference for autologous over implant-based BR due to lower risk of long-term complications and support for immediate and delayed-immediate reconstructive approaches. Nevertheless, it was strongly believed that PMRT is not an absolute contraindication for implant-based or other types of BR, but no specific recommendations regarding implant positioning, use of mesh or timing were made due to absence of high-quality evidence. The panel endorsed use of patient-reported outcomes in clinical practice. It was acknowledged that the shape and size of reconstructed breasts can hinder radiotherapy planning and attention to details of PMRT techniques is important in determining aesthetic outcomes after immediate BR.

Conclusions

The panel endorsed the need for prospective, ideally randomised phase III studies and for surgical and radiation oncology teams to work together for determination of optimal sequencing and techniques for PMRT for each patient in the context of BR

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Autologous breast reconstruction is increasingly preferred over implants in the setting of radiation therapy.

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Use of patient-reported outcomes is endorsed.

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Shape and size of reconstructed breasts can hinder radiotherapy planning.

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There is a need for randomised phase III trials.

Abstract GS4-03: Patient-reported outcomes (PROs) for the intergroup sentinel mamma study (INSEMA, GBG75, ABCSG43): Persistent impact of axillary surgery on arm and breast symptoms in early breast cancer

Background: Despite increasing evidence disfavoring axillary lymph node dissection (ALND) for locoregional control, it remains part of guidelines for breast cancer (BC) treatment. In an attempt to re-evaluate standard local therapy, the INSEMA trial was designed to assess non-inferiority of avoiding sentinel lymph node biopsy (SLNB) or completion ALND (cALND) in early-stage clinically node-negative BC patients. Here we present PROs from the INSEMA trial. Methods: INSEMA (NCT02466737) investigates non-inferiority of invasive disease-free survival (iDFS) after no axillary surgical staging versus SLNB (first randomization 1:4) in patients with clinically node-negative BC (tumor size ≤5 cm) and primary breast-conserving surgery (BCS). In case of pN1a(sn) in the SLNB arm, patients underwent a second randomization to either SLNB alone or cALND (1:1). PROs were assessed at baseline (pre-surgery) and at 1, 3, 6, 12, and 18 months after final axillary surgery using the European Organisation for Research and Treatment of Cancer Quality-of-Life Questionnaire (EORTC QLQ-C30) and its breast cancer (BR23) module. Higher scores of C30 and BR23 (range 0-100) indicate better functioning and global health status (GHS)/quality of life (QoL) or worse symptom severity, respectively. The QoL scores were compared using the Mann-Whitney U test based on the safety set. Results: Between September 2015 and April 2019, 5,502 patients were recruited for the 1st randomization and 5,173 of them were included in the intent-to-treat set (4,138 SLNB vs 1,035 no SLNB). Patient and tumor characteristics were well-balanced between treatment arms. Median age at diagnosis was 62.0 years (range 24.0 - 89.0). Overall, recruited patients presented with low-risk BC marked by 85.6% clinically stage T1, 98.5% hormone-receptor positivity, 2.4% HER2-positivity, and 3.7% G3 tumors. The majority (73.5%) had an invasive carcinoma of no special type (72.8% in SLNB vs 76.0% in no SLNB arm) and 87.0% had Ki-67 ≤ 20%. Questionnaire completion response remained high throughout the trial: n=3,915 (75.7%) returned questionnaires at 1 month after final axillary surgery, n=3,938 (76.1%) at 3 months, n=4,024 (77.8%) at 6 months, n=3,907 (75.5%) at 12 months, and n=3,637 (70.3%) at 18 months. All QoL baseline parameters regarding GHS, functional scales, and symptom scales/items were well-balanced between arms (total 4,117 SLNB vs 1,056 no SLNB as treated; 270 of 4,117 received cALND). There were significant differences for the BRBS (breast symptoms) and BRAS (arm symptoms) scores favoring the no SLNB group in all post-baseline assessments Patients in the SLNB group showed persistent higher scores for BRAS (differences in mean values ≥5.0 points at all times of assessment) including pain, arm swelling, and impaired mobility in all postoperative visits with the highest difference at 1 month after final surgery (mean scores, 23.6 vs. 12.8, p&lt;0.001). Differences between treatment arms regarding BRBS including pain, breast swelling, hypersensitivity, and other skin problems showed a smaller range, but still a continuous trend for improved QoL in the no SLNB arm. Scoring of the QLQ-C30 questionnaire revealed no relevant differences between the treatment groups postoperatively. Conclusions: This is one of the first randomized trials investigating the omission of SLNB in clinically node-negative patients and the first to report QoL data. Patients with no SLNB benefitted regarding arm symptoms/functioning while no relevant differences in other QoL scales were seen. Data for the primary outcome of the study (iDFS) are expected for the end of 2024.

Citation Format: Bernd Gerber, Angrit Stachs, Kristina Veselinovic, Silke Polata, Thomas Müller, Thorsten Kühn, Jörg Heil, Beyhan Ataseven, Roland Reitsamer, Guido Hildebrandt, Michael Knauer, Michael Golatta, Andrea Stefek, Dirk-Michael Zahm, Marc Thill, Valentina Nekljudova, David Krug, Fenja Seither, Sibylle Loibl, Toralf Reimer. Patient-reported outcomes (PROs) for the intergroup sentinel mamma study (INSEMA, GBG75, ABCSG43): Persistent impact of axillary surgery on arm and breast symptoms in early breast cancer [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr GS4-03.

Abstract P1-21-08: Brain metastases (BM) from breast cancer: Real-word data from the Austrian AGMT_MBC-registry

Background: BM are generally associated with poor prognosis and with neurological impairments making BM a major limitation of life expectancy and quality of life in MBC. Real-world data are needed in order to quantify and better characterize this special clinical situation. Here, we present data from the MBC registry of the Austrian Study Group for Medical Tumor Therapy (AGMT-MBC-Registry). Methods: The AGMT-MBC-Registry is an ongoing multicenter registry for MBC patients in Austria. Patients with available hormone receptor and HER2 status and sufficient outcome data were included in this analysis. Unadjusted, univariate overall survival (OS) probabilities were calculated by the Kaplan-Meier method and compared by the log-rank test; multivariable adjusted hazard ratios (HR) were estimated by Cox regression models. HR were estimated with diagnosis of BM as time-dependent variable. Logistic regression was performed to investigate the probability of developing BM. Multivariable analyses included the following parameters: breast cancer subtype (luminal-like vs. HER2+ vs. TNBC), age at diagnosis of metastatic disease (continuous, in Cox regression as interaction with menopausal status), DFS (de novo metastatic or ≥ 24 months vs. &lt; 24 months), visceral disease (yes vs. no) and number of metastatic sites (1 vs 2-3 vs. ≥4) at diagnosis of metastatic disease. Results: As of 15/04/2021, 2024 patients were included in the registry. Out of 1691 evaluable patients, 306 (18.1%) had documented BM. The incidence at diagnosis of metastatic disease and the overall incidence during the course of disease was significantly higher in HER2+ (9.5% [13/137] and 36.5% [50/137]) and triple-negative tumors (11.9% [38/318] and 27.7% [88/318]) compared to luminal-like tumors (3.3% [41/1236] and 13.6% [168/1236]) (both P&lt;0.001). Besides subtype, ≥4 metastatic sites at diagnosis of metastatic disease and age were statistically significant associated with BM in logistic regression analysis.Median time to BM calculated from the date of diagnosis of metastatic disease was 11.3 months (95%CI 9.3-13.3) in the total population with BM, 12.7 months (95%CI 7.3-16.0) in HER2+, 5.2 months (95%CI 1.8-10.3) in triple-negative and 15.4 months (95%CI 8.4-19.5) in luminal disease, respectively. Interestingly, 13.7% of patients (42/306) had BM as first metastatic site without extracranial disease. The median number of systemic therapy-lines before and after diagnosis of BM was 1 (range 0-8) and 1 (range 0-10), respectively. Most of the patients with BM (80.1%) received radiotherapy; 12.7% focal radiotherapy, 69.8% whole brain irradiation and 9.0% both types of radiotherapy (8.5% unknown). After a median follow-up of 72.3 months (95%-CI 68.6-80.0), patients with BM had a significantly shorter median OS (7.5 months) compared to patients without BM (38.4 months) both in univariate (HR 3.58; 95%CI 3.11-4.11; P&lt;.001) and multivariable analysis (HR 3.70; 95%CI 3.18-4.32; P&lt;.001). OS in patients with BM differed significantly between the three breast cancer subtypes with a median OS of 36.3 months (95%CI 30.5-47.9), 33.5 months (95%CI 22.9-45.5) and 13.2 months (95%CI 11.1-18.4) in luminal, HER2+ and TNBC, respectively (overall log-rank P&lt;0.001). Similarly, the time from diagnosis of BM and death was significantly shorter in TNBC (4.1 months; 95%CI 3.4-6.3) compared to luminal (9.7 months; 95%CI 6.8-13.7) and HER2+ breast cancer (10.7 months; 95%CI 9.1-26.2) (overall log-rank P&lt;0.001). Conclusion: Almost 20% of patients with MBC develop BM during their course of disease, with a higher incidence in HER2+ and triple-negative disease. Besides effective prevention strategies improved systemic and local therapies are needed to minimize morbidity and improve outcome in these patients.

Citation Format: Simon Peter Gampenrieder, Gabriel Rinnerthaler, Christoph Tinchon, Andreas Petzer, Marij Balic, Sonja Heibl, August F Zabernigg, Daniel Egle, Margit Sandholzer, Florian Roitner, Johannes Andel, Petra Pichler, Christopher Hager, Michael Knauer, Michael Hubalek, Christian F Singer, Richard Greil. Brain metastases (BM) from breast cancer: Real-word data from the Austrian AGMT_MBC-registry [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P1-21-08.

Abstract P1-16-03: Response pattern to chemotherapy in metastatic breast cancer (MBC): Real-word data from the Austrian AGMT_MBC-Registry

Background: Despite the advances by targeted therapies, particularly in HER2-positive and hormone receptor (HR)-positive metastatic breast cancer (MBC), chemotherapy remains a mainstay of the treatment in all breast cancer subtypes. Response probabilities to chemotherapy seem to decrease with increasing lines of treatment, but little is known about the response dependency on the previous therapy line. Here, we present data from the MBC registry of the Austrian Study Group for Medical Tumor Therapy (AGMT-MBC-Registry). Methods: The AGMT-MBC-Registry is an ongoing multicenter registry for MBC patients in Austria. Patients with available hormone receptor and negative HER2 status, at least two consecutive lines of chemotherapy and sufficient progression-free survival (PFS) data were included in this analysis. Multivariable adjusted hazard ratios (HR) for PFS were estimated by Cox regression models and included the following parameters: age, HR status, disease-free survival (de novo metastatic or ≥ 24 months vs. &lt; 24 months), visceral disease, number of involved metastatic sites at diagnosis of MBC, chemotherapy treatment line, and response in previous treatment line. Response was defined as PFS &gt; 4 month and non-response as a PFS ≤ 4 month. Cox model was extended as proposed by Andersen and Gill due to possibility of multiple events per patient and thereby resulting dependencies (Sousa-Ferreira & Abreu, 2019). Results: As of 15/04/2021, 2024 patients were included in the registry. Out of them, 405 patients (20.0%) had documented HER2 negative disease with at least two lines of consecutive chemotherapy. Median PFS for first-, second-, third-, and forth-line chemotherapy were 6.0 months (95% CI 5.5-6.5), 3.7 months (95% CI 3.1-4.3), 2.9 months (95% CI 2.5-3.2), and 2.8 months (95% CI 2.6-3.2), respectively. Median overall survival was 31.8 months (95% CI 27.2-34.8). Median number of chemotherapy lines was 3 (range 2-8). The most commonly used cytotoxic agents were paclitaxel and capecitabine in first- and second-line, and eribulin in third-, and fourth-line chemotherapy. Combinations of more than one cytotoxic drug were given in 36%, 29%, 28% in first-, second-, and third/fourth-line. Patients who did not respond to the previous therapy line, had a response in 43% (95% CI 33-53), 34% (95% CI 25-43), and 30% (95% CI 21-39) to second-, third-, and fourth-line. In those patients, investigator assessed overall response rate (partial remission or complete remission) was 27% (95% CI 13-40), 23% (95% CI 9-37), and 33% (95% CI 16-51), respectively. A response to third-line chemotherapy in patients who did not respond to first- and second-line therapy, was seen in 16.7% of patients. Ratios between PFS of interest and PFS of the previous treatment line were 0.63 (95% CI 0.55-0.68), 0.57 (95% CI 0.41-0.62), and 0.76 (95% CI 0.58-0.9) in second-, third-, and forth-line therapy. In multivariable analysis, responses in second- to fourth-line therapy were statistically significant associated with disease-free survival (HR 0.75, P=0.022), and treatment line (HR 1.17 per increasing treatment line, P=0.004), but not for the response to the previous treatment line (HR 0.85, P=0.068). Conclusion: A continuously decreasing PFS for cytotoxic drugs from treatment line to treatment line was confirmed in our analysis. However, in multivariable analysis, response, defined as PFS &gt; 4 months, was not statistically associated with response to the previous treatment line. Therefore, a lack of response to first, second-, - or third-line chemotherapy should not trigger discontinuation of anticancer therapy in case of further available treatment options.

Citation Format: Gabriel Rinnerthaler, Simon P Gampenrieder, Christoph Tinchon, Andreas Petzer Petzer, Marija Balic, Heibl Sonja, August F Zabernigg, Daniel Egle, Margit Sandholzer, Florian Roitner, Johannes Andel, Petra Pichler, Christophe Hager, Michael Hubalek, Michael Knauer, Christian F Singer, Richard Greil. Response pattern to chemotherapy in metastatic breast cancer (MBC): Real-word data from the Austrian AGMT_MBC-Registry [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P1-16-03.

Landscape of HER2-low metastatic breast cancer (MBC): results from the Austrian AGMT_MBC-Registry

Background

About 50% of all primary breast cancers show a low-level expression of HER2 (HER2-low), defined as immunohistochemically 1+ or 2+ and lack of HER2 gene amplification measured by in situ hybridization. This low HER2 expression is a promising new target for antibody–drug conjugates (ADCs) currently under investigation. Until now, little is known about the frequency and the prognostic value of low HER2-expression in metastatic breast cancer (MBC).

Patients and methods

The MBC-Registry of the Austrian Study Group of Medical Tumor Therapy (AGMT) is a multicenter nationwide ongoing registry for MBC patients in Austria. Unadjusted, univariate survival probabilities of progression-free survival (PFS) and overall survival (OS) were calculated by the Kaplan–Meier method and compared by the log-rank test. Multivariable adjusted hazard ratios were estimated by Cox regression models. In this analysis, only patients with known HER2 status and available survival data were included.

Results

As of 11/15/2020, 1,973 patients were included in the AGMT-MBC-Registry. Out of 1,729 evaluable patients, 351 (20.3%) were HER2-positive, 608 (35.2%) were HER2-low and 770 (44.5%) were completely HER2-negative (HER2-0). Low HER2-expression was markedly more frequent in the hormone-receptor(HR)+ subgroup compared to the triple-negative subgroup (40% vs. 23%). In multivariable analysis, low HER2 expression did not significantly influence OS neither in the HR+ (HR 0.89; 95% CI 0.74–1.05; P = 0.171) nor in the triple-negative subgroup (HR 0.92; 95% CI 0.68–1.25; P = 0.585), when compared to completely HER2-negative disease. Similar results were observed when HER2 IHC 2+ patients were compared to IHC 1+ or 0 patients.

Conclusion

Low-HER2 expression did not have any impact on prognosis of metastatic breast cancer in this real-world population.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13058-021-01492-x.

Tailored axillary surgery in patients with clinically node-positive breast cancer: Pre-planned feasibility substudy of TAXIS (OPBC-03, SAKK 23/16, IBCSG 57-18, ABCSG-53, GBG 101)

Aim

We developed tailored axillary surgery (TAS) to reduce the axillary tumor volume in patients with clinically node-positive breast cancer to the point where radiotherapy can control it. The aim of this study was to quantify the extent of tumor load reduction achieved by TAS.

Methods

International multicenter prospective study embedded in a randomized trial. TAS is a novel pragmatic concept for axillary surgery de-escalation that combines palpation-guided removal of suspicious nodes with the sentinel procedure and, optionally, imaging-guided localization. Pre-specified study endpoints quantified surgical extent and reduction of tumor load.

Results

A total of 296 patients were included at 28 sites in four European countries, 125 (42.2%) of whom underwent neoadjuvant chemotherapy (NACT) and 71 (24.0%) achieved nodal pathologic complete response. Axillary metastases were detectable only by imaging in 145 (49.0%) patients. They were palpable in 151 (51.0%) patients, of whom 63 underwent NACT and 21 had residual palpable disease after NACT. TAS removed the biopsied and clipped node in 279 (94.3%) patients. In 225 patients with nodal disease at the time of surgery, TAS removed a median of five (IQR 3–7) nodes, two (IQR 1–4) of which were positive. Of these 225 patients, 100 underwent ALND after TAS, which removed a median of 14 (IQR 10–17) additional nodes and revealed additional positive nodes in 70/100 (70%) of patients. False-negative rate of TAS in patients who underwent subsequent ALND was 2.6%.

Conclusions

TAS selectively reduced the tumor load in the axilla and remained much less radical than ALND.

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Tailored axillary surgery is a novel concept for clinically node-positive breast cancer

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Tailored axillary surgery selectively removes positive lymph nodes

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Tailored axillary surgery is much less radical than axillary dissection

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Tailored axillary surgery removes the clipped node in the vast majority of patients

Prepectoral versus subpectoral implant-based breast reconstruction after skin-sparing mastectomy or nipple-sparing mastectomy (OPBC-02/ PREPEC): a pragmatic, multicentre, randomised, superiority trial

INTRODUCTION

The emphasis on aesthetic outcomes and quality of life (QoL) has motivated surgeons to develop skin-sparing or nipple-sparing mastectomy (SSM/ NSM) for breast cancer treatment or prevention. During the same operation, a so-called immediate breast reconstruction is performed. The breast can be reconstructed by positioning of a breast implant above (prepectoral) or below (subpectoral) the pectoralis major muscle or by using the patients' own tissue (autologous reconstruction). The optimal positioning of the implant prepectoral or subpectoral is currently not clear. Subpectoral implant-based breast reconstruction (IBBR) is still standard care in many countries, but prepectoral IBBR is increasingly performed. This heterogeneity in breast reconstruction practice is calling for randomised clinical trials (RCTs) to guide treatment decisions.

METHODS AND ANALYSIS

International, pragmatic, multicentre, randomised, superiority trial. The primary objective of this trial is to test whether prepectoral IBBR provides better QoL with respect to long-term (24 months) physical well-being (chest) compared with subpectoral IBBR for patients undergoing SSM or NSM for prevention or treatment of breast cancer. Secondary objectives will compare prepectoral versus subpectoral IBBR in terms of safety, QoL and patient satisfaction, aesthetic outcomes and burden on patients. Total number of patients to be included: 372 (186 per arm).

ETHICS AND DISSEMINATION

This study will be conducted in compliance with the Declaration of Helsinki. Ethical approval has been obtained for the lead investigator's site by the Ethics Committee 'Ethikkommission Nordwest- und Zentralschweiz' (2020-00256, 26 March 2020). The results of this study will be published in a peer-reviewed medical journal, independent of the results, following the Consolidated Standards of Reporting Trials standards for RCTs and good publication practice. Metadata describing the type, size and content of the datasets will be shared along with the study protocol and case report forms on public repositories adhering to the FAIR (Findability, Accessibility, Interoperability, and Reuse) principles.

TRIAL REGISTRATION NUMBER

NCT04293146.

Canadian Society of Clinical Chemists (CSCC) consensus guidance for testing, selection and quality management of SARS-CoV-2 point-of-care tests

OBJECTIVES

A consensus guidance is provided for testing, utility and verification of SARS-CoV-2 point-of-care test (POCT) performance and implementation of a quality management program, focusing on nucleic acid and antigen targeted technologies.

DESIGN AND METHODS

The recommendations are based on current literature and expert opinion from the members of Canadian Society of Clinical Chemists (CSCC), and are intended for use inside or outside of healthcare settings that have varied levels of expertise and experience with POCT.

RESULTS AND CONCLUSIONS

Here we discuss sampling requirements, biosafety, SARS-CoV-2 point-of-care testing methodologies (with focus on Health Canada approved tests), test performance and limitations, test selection, testing utility, development and implementation of quality management systems, quality improvement, and medical and scientific oversight.

Breast Cancer Management During the COVID-19 Pandemic: The Senologic International Society Survey

Objective

In early 2020, the spread of coronavirus disease-2019 (COVID-19) led the World Health Organization to declare this disease a pandemic. Initial epidemiological data showed that patients with cancer were at high risk of developing severe forms of COVID-19. National scientific societies published recommendations modifying the patients' breast cancer (BC) management to preserve, in theory, quality oncologic care, avoiding the increased risk of contamination. The Senology International Society (SIS) decided to take an inventory of the actions taken worldwide. This study investigates COVID-19-related changes concerning BC management and analyzes the will to maintain them after the pandemic, evaluating their oncological safety consequences.

Materials and Methods

SIS network members participated in an online survey using a questionnaire (Microsoft^® Forms) from June 15^th to July 31^st, 2020.

Results

Forty-five responses from 24 countries showed that screening programs had been suspended (68%); magnetic resonance imagines were postponed (73%); telemedicine was preferred when possible (71%). Surgeries were postponed: reconstructive (77%), for benign diseases (84%), and in patients with significant comorbidities (66%). Chemotherapy and radiotherapy protocols had been adapted in 28% of patients in both. Exception for telemedicine (34%), these changes in practice should not be continued.

Conclusion

The SIS survey showed significant changes in BC's diagnosis and treatment during the first wave of the COVID-19 pandemic, but most of these changes should not be maintained. Indeed, women have fewer severe forms of COVID-19 and are less likely to die than men. The risk of dying from COVID-19 is more related to the presence of comorbidities and age than to BC. Stopping screening and delaying treatment leads to more advanced stages of BC. Only women aged over 65 with BC under treatment and comorbidities require adaptation of their cancer management.

[Inpatient treatment of Breast Cancer - the essentials]

Inpatient treatment of Breast Cancer - the essentials Abstract. The treatment of breast cancer patients in the inpatient setting has dramatically changed over the last decades. Modern operative techniques resulted in tremendous reductions of morbidity and complication rates. New breast conserving surgical techniques and the consequent reduction of unnecessary extensive lymph node surgery resulted in a significantly shorter length of stay. This in combination with the system of lump compensations and diagnosis related groups (DRG) led to the fact that the inpatient treatment is just another part of a complex multidisciplinary diagnostic and therapeutic algorithm. Most of the steps are being organized and performed in the outpatient setting. The overall effort has increased nevertheless due to modern quality standards and certification of breast centers.

Superparamagnetic Silicon Carbonitride Ceramic Fibers Through In Situ Generation of Iron Silicide Nanoparticles During Pyrolysis of an Iron-Modified Polysilazane

Ceramic fibers are high-tech structural key components of ceramic matrix composites (CMCs), which are a very promising class of materials for applications in next-generation turbines, especially nonoxide ceramic fibers, usually produced by the polymer-derived ceramics (PDC) route, which possess the enhanced mechanical and thermostructural properties necessary to withstand the harsh conditions (temperature and atmosphere) imposed on CMCs. However, recycling composite materials, such as fiber-reinforced polymers and CMCs, is still a big challenge. Here, we present for the first time the processing of superparamagnetic iron-containing ceramic fibers, which, due to their magnetic properties, can be separated from the matrix material of a composite. The synthesis strategy of the novel functional ceramic fibers is based on a tailored reaction of polyorganosilazane with an iron complex, resulting in a suitable, meltable polymer. After melt-spinning and curing, subsequent pyrolysis leads to superparamagnetic ceramic fibers with a saturation magnetization of 1.54 emu g^-1 because of in situ-formed iron silicide nanoparticles of an average size of 7.5 nm, homogeneously dispersed in an amorphous SiCNO matrix. Moreover, the ceramic fibers exhibit a tensile strength of 1.24 GPa and appropriate oxidation resistance. The developed versatile reaction strategy allows also for the incorporation of other elements to implement further functionalities for processing of multifunctional composites.

Abstract PS12-21: First-line treatment of hormone receptor positive metastatic breast cancer (MBC) in everyday practice: Results from the Austrian AGMT_MBC-Registry

Background: International guidelines recommend endocrine-based first-line therapy [ET] in hormone receptor-positive, HER2-negative (HR+/HER2- or luminal) metastatic breast cancer (MBC), nowadays in combination with a CDK4/6 inhibitor. Several real-word data suggest, however, that in daily practice up to 40% of patients with luminal MBC receive chemotherapy in first-line. To clarify the treatment landscape in an Austrian population of HR+/HER2- MBC patients, we analyzed the data from the MBC registry of the Austrian Study Group for Medical Tumor Therapy (AGMT-MBC-Registry). In addition, we investigated the influence of different treatment strategies on overall survival (OS). Methods: The AGMT-MBC-Registry is an ongoing multicenter registry for MBC patients in Austria. Only patients with HR+/HER2- MBC with available ER and HER2 status and sufficient outcome data were included in this analysis. Unadjusted, univariate survival probabilities of PFS and OS were calculated by the Kaplan-Meier method and compared by the log-rank test, multivariate hazard ratios (HR) were estimated by Cox regression models. A multivariate analysis including the following parameters was performed for first-line PFS and OS: age (continuous, as interaction with menopausal status), menopausal status (pre- vs postmenopausal vs unknown,), DFS (de novometastatic vs &lt; 24 months vs ≥ 24 months), (neo)adjuvant chemotherapy (yes vs no), grading (1+2 vs 3 vs unknown), visceral disease (yes vs no) and number of metastatic sites (1 vs 2-3 vs ≥4), first-line treatment (ET+CDK4/6i vs ET vs chemotherapy +/- bevacizumab +/- ET). Results: As of 24/06/2020, 1904 patients were included in the AGMT-MBC-Registry. Out of 1633 evaluable patients, 931 (57.01%) had HR+/HER2- disease and had received at least one treatment line for metastatic disease. In first-line, 577 (62.0%) patients received endocrine-based therapy (356 [61.7%] ET, 172 [29.8%] ET+CDK4/6i, 49 [8.5%] ET+Targeted other), and 354 (38.0%) received chemotherapy. The proportion of chemotherapy treated patients was slightly higher in pre- vs. postmenopausal women (41/94=43.6% vs. 222/664=33.4%) but decreased significantly over time (&lt;2010: 60.3%; 2010-2015: 44.8%; &gt;2015: 19.7%). In multivariate analysis, both ET and ET+CDK4/6i were significantly associated with longer first-line PFS and OS compared to chemotherapy (Table 1).

The most frequently used drugs across all treatment-lines were aromatase inhibitors (77.9%), fulvestrant (53.9%; 39.8% in first-line and 36.3% in second-line), tamoxifen (17.2%), CDK4/6 inhibitors (40.0%; 48.9% in first-line and 21.8% in second-line), everolimus (18.9%; 30.7% in second-line and 69.3% in ≥ third-line), taxanes (41.6%), capecitabine (35.0%), anthracyclines (28.6%), vinorelbine (17.0%) and eribulin (12.6%). Conclusion: In our registry, first-line chemotherapy for luminal MBC was significantly associated with an inferior PFS and OS compared to endocrine-based therapy. Because of the retrospective design of the study, biases influencing these results cannot be fully excluded, however, our data suggest that first-line chemotherapy should be avoided in luminal MBC.

Adjusted analysisET vs. chemotherapyET+CDK4/6i vs. chemotherapy1st-line PFSHR 0.63; 95%CI 0.52-0.77; P&lt;0.001HR 0.19; 95%CI 0.13-0.29; P&lt;0.001OSHR 0.59; 95%CI 0.49-0.72; P&lt;0.001HR 0.35; 95%CI 0.23-0.51, P&lt;0.001

Citation Format: Gabriel Rinnerthaler, Simon P Gampenrieder, Christoph Tinchon, Andreas Leo Petzer, Christoph Suppan, Sonja Heibl, Daniela Voskova, August F Zabernigg, Daniel Egle, Margit Sandholzer, Christian F Singer, Florian Roitner, Johannes Andel, Michael Hubalek, Michael Knauer, Richard Greil. First-line treatment of hormone receptor positive metastatic breast cancer (MBC) in everyday practice: Results from the Austrian AGMT_MBC-Registry [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS12-21.

Abstract PS1-41: Does complete surgical removal of metastases in oligometastatic breast cancer improve survival? A matched-pair analysis of the AGMT_MBC-registry

Background: Metastatic breast cancer (MBC) is generally thought to be a systemic and incurable disease requiring systemic therapy. However, surgical resection of oligometastatic disease might be of benefit similar to other malignant diseases. Here, we present the results from a matched analysis of patients undergoing radical surgery of metastases.

Methods: The MBC registry of the Austrian Study Group for Medical Tumor Therapy (AGMT) is an ongoing multicenter registry for MBC patients in Austria. Patients undergoing surgical removal of all metastatic sites (+/- primary tumor and lymph node dissection) were identified and matched 1:1 according to disease-free survival (de novo metastatic vs. &lt; 24 vs. ≥ 24 months), location of metastases, subtype (HR+/HER2- vs. HR+/HER2+ vs. HR-/HER2+ vs. triple-negative) and age (≥ 60 vs. &lt; 60). OS was defined as time from diagnosis of metastatic disease until death. Only patients with available matching parameters and sufficient outcome data were included in this analysis.

Results: As of 24/06/2020, 1904 patients were enrolled into the AGMT_MBC-Registry; 24 of them received surgery of metastases and 23 had a complete match with patients without surgery. In the surgery group, five patients (21.7%) received immediate postperative chemotherapy and 80.0% received further chemotherapy after surgery. Out of patients with HR+ disease (n=15), 86.7% received endocrine therapy prior and/or after surgery. We found a numerically but not statistically significant longer overall OS in patients undergoing surgery (47.4 vs. 29.6 months, HR 0.61; 95%CI 0.30-1.24; P=0.171). Two, five and ten year survival estimates were 82.6% (95%CI 68.5-99.6), 31.3% (95%CI 15.7-62.5) and 31.3% (95%CI 15.7-62.5) in the surgery group and 59.1% (95%CI 41.7-83.7), 24.8% (95%CI 11.7-52.6) and 13.2% (95%CI 4.0-43.1) in the non-surgery group, respectively. The largest benefit for surgery was found in the luminal and HER2-positive subtypes, while no benefit was observed in the triple-negative subgroup.

Conclusion: Radical surgery of all metastases seems to improve survival, especially in luminal and HER2-positive subtypes, however, the analysis did not reach statistical significance, most probably due to the low patient number. Furthermore, because of the retrospective and non-randomized design, a systematic bias cannot be totally excluded.

Citation Format: Simon Peter Gampenrieder, Gabriel Rinnerthaler, Christoph Tinchon, Andreas Leo Petzer, Christoph Suppan, MD, Sonja Heibl, Daniela Voskova, August F Zabernigg, MD, Daniel Egle, MD, Margit Sandholzer, MD, Christian F Singer, Florian Roitner, Johannes Andel, Michael Hubalek, Michael Knauer, Richard Greil. Does complete surgical removal of metastases in oligometastatic breast cancer improve survival? A matched-pair analysis of the AGMT_MBC-registry [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS1-41.

Abstract OT-04-03: Tailored axillary surgery with or without axillary lymph node dissection followed by radiotherapy in patients with clinically node-positive breast cancer (SAKK 23/16 / IBCSG 57-18 / ABCSG-53 / GBG 101 - TAXIS): A multicenter randomized phase III trial

Background Main weaknesses of neoadjuvant chemotherapy (NACT) to avoid axillary dissection (ALND) in patients with clinically node-positive breast cancer are frequent failure of achieving nodal pathologic complete response (pCR) and administration of chemotherapy even though not indicated otherwise in many cases. Tailored axillary surgery (TAS) was designed to selectively remove positive nodes and omit ALND in patients with clinically node-positive breast cancer either in the upfront surgery setting or in case of residual nodal disease after neoadjuvant therapy, which distinguishes this trial from all others ongoing and published. Trial design In this international, multi-center, phase-III, non-inferiority randomized controlled trial, including 61 study sites from six countries, we plan to randomize 1500 patients to either receive TAS followed by ALND and regional nodal irradiation excluding the dissected axilla, or receive TAS only followed by regional nodal irradiation including the full axilla. TAS consists of selective removal of the sentinel lymph nodes (SLNs) and all palpably suspicious findings, thereby tailoring the extent of axillary surgery to the extent of axillary disease, followed by specimen radiography to document removal of the clip placed in the sampled node. Imaging-guided localization is encouraged to increase the chances of clip removal. All patients undergo adjuvant whole-breast irradiation after breast conserving surgery and chest wall irradiation after mastectomy. Inclusion of internal mammary nodes is recommended irrespective of treatment arm. ClinicalTrials.gov Identifier: NCT03513614. Inclusion criteria - Clinically node-positive breast cancer (all molecular subtypes allowed) - Node-positivity palpable or detectable only by imaging at time of initial diagnosis - Newly diagnosed or isolated in-breast recurrence or second ipsilateral breast cancer after previous breast conserving surgery and sentinel procedure and at least 3 years disease free and no prior axillary dissection or axillary RT. - In case of prior neoadjuvant treatment: residual disease (including residual ITCs) confirmed by pathology at the time of surgery - Clipping of sampled axillary lymph node Exclusion criteria - Absence of clip in the specimen radiography - Palpable disease left behind in the axilla after TAS - No SLN identified in the axilla Specific aims To test the hypothesis that treatment with TAS and axillary radiotherapy is non-inferior to ALND in terms of disease-free survival (DFS) of clinically node-positive breast cancer patients. Secondary objective is to test if quality of life is significantly better with TAS and axillary radiotherapy compared to ALND. Statistical methods With type I error 5% and power 80%, 385 events will be needed to show non-inferiority of TAS and axillary RT in comparison to ALND with a non-inferiority hazard ratio (HR) of 1.289 (corresponding to a DFS at 5 years of 80% in the ALND arm and 75% in the TAS and axillary RT arm), including one interim analysis for efficacy/futility after 20% of the required events have occurred. The sample size needed is 1500 patients (750 per arm). The HR and one-sided 95% confidence interval will be calculated using a Cox regression model based on the per-protocol set. Present accrual and target accrual The trial was activated on 31 July 2018 and the first patient was randomized on 07 August 2018. As of 03 July 2020, 291 patients have been randomized. Accrual is currently running according to protocol and is planned until end of 2023 with the primary endpoint analysis expected in 2029. Contact information Prof. Dr. Walter Paul Weber, University Hospital Basel; Tel: +41 61 328 61 49; Walter.Weber@usb.ch

Citation Format: Walter Paul Weber, Guido Henke, Stefanie Hayoz, Karin Ribi, Stefanie Seiler, Charlotte Maddox, Thomas Ruhstaller, Daniel Rudolf Zwahlen, Simone Muenst, Markus Ackerknecht, Florian Fitzal, Mihály Újhelyi, Christian Kurzeder, Loïc Lelièvre, Christoph Tausch, Daniel Egle, Jörg Heil, Zoltan Matrai, Michael Knauer. Tailored axillary surgery with or without axillary lymph node dissection followed by radiotherapy in patients with clinically node-positive breast cancer (SAKK 23/16 / IBCSG 57-18 / ABCSG-53 / GBG 101 - TAXIS): A multicenter randomized phase III trial [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr OT-04-03.

Abstract OT-23-03: Pre- versus sub-pectoral implant-based breast reconstruction after skin-sparing mastectomy or nipple-sparing mastectomy (OPBC-02 PREPEC): A pragmatic, multicenter, randomized, superiority trial

Background The emphasis on aesthetic outcomes and quality of life (QoL) has motivated surgeons to develop skin- and nipple-sparing mastectomy (SSM/NSM) for breast cancer (BC) treatment or prevention. Immediate breast reconstruction is based on implants or autologous tissue. The optimal positioning of the implant is not clear: While pre-pectoral positioning respects the anatomic position of the mammary gland and avoids surgery-induced alterations of the pectoralis major muscle, the lack of muscle coverage may increase the risk of additional surgical interventions due to major complications. The Oncoplastic Breast Consortium (OPBC) identified this knowledge gap as research priority in 2019.

Trial design International, multicenter study with a superiority trial design and two parallel groups with 1:1 random allocation to pre- or sub-pectoral implant-based breast reconstruction (IBBR). Following a pragmatic approach, randomly assigned IBBR will be performed according to the surgeons’ usual care by use of a one- or two-stage approach with or without adjunctive mesh. Follow-up visits are performed within routine care (visits at 10 days and at 1, 6, 12, 18 and 24 months after surgery). Oncological follow-up will be conducted annually for 10 years. ClinicalTrials.gov identifier: NCT04293146.

Eligibility We include women ≥ 18 years, with an indication for NSM or SSM and IBBR in the therapeutic or risk-reducing setting, the ability to complete QoL questionnaires and the adequateness of skin flap(s) for pre-pectoral IBBR (intraoperative decision of the surgeon).

Specific aims The primary objective is to test whether pre-pectoral IBBR provides better QoL with respect to long-term (24 months) physical well-being of the chest (BREAST-Q) compared to sub-pectoral IBBR for patients undergoing SSM or NSM for prevention or treatment of BC. Secondary endpoints include loss of expander or implant, complications, other BREAST-Q QoL and patient satisfaction domains, aesthetic outcomes and recurrence free survival. Interference of different dose distributions of radiation therapy and its consequences on the distribution of local tumor recurrences will be assessed.

Statistical methods The primary analysis will be performed on the full analysis set following the intention-to-treat principle. To test the primary hypothesis, a linear mixed model will be fitted with the BREAST-Q score as response variable and treatment assignment as independent variable. The analysis will be adjusted for baseline BREAST-Q score, stratification factors (i.e. uni- vs bilateral surgery and NSM vs SSM) and other potential confounders. A random intercept to account for the center effect will be included. As a sensitivity analysis, an unadjusted t-test will be performed on the BREAST-Q score change from baseline to compare the two treatment arms. The sample size was determined for the primary endpoint, with an expected mean score of 76 points for sub-pectoral and 80 points for pre-pectoral implants. The clinically relevant difference to be detected in this superiority design is 4 points, with an expected common standard deviation of 13 points. A sample size of 334 patients provides an 80% power for a two-sided t-test at level α = 0.05. Compensating for a 10% dropout rate, the total sample size was calculated to include 372 patients.

Present accrual and target accrual By June 2020, one study site (Basel) has been initiated. During a 21-month recruitment period, we plan to include 372 patients at 21 sites in Switzerland, USA, China, Austria, Germany, Hungary and Sweden.

Contact information Prof. Dr. Walter Paul Weber, Chefarzt Brustchirurgie, Breast Surgeon SSO, Universitätsspital Basel, Spitalstrasse 21, CH-4031 Basel, Tel: +41 61 328 61 49, Walter.Weber@usb.ch

Citation Format: Walter Paul Weber, Elisabeth A Kappos, Meredith M Regan, Giusi Moffa, Yves Harder, Karin Ribi, Shelley Potter, Andrea Pusic, Mathias K Fehr, Lars G Hemkens, Thomas Holzbach, Jian Farhadi, Colin Simonson, Michael Knauer, Ralph Verstappen, Heiner Bucher, Daniel Zwahlen, Frank Zimmermann, Matthias Schwenkglenks, Rosine Mucklow, Vesna Bjelic-Radisic, Amelia Chiorescu, Yoon Chun, Subrina Farah, Xiasong Chen, Linda Nigard, Sherko Kümmel, Roland Reitsamer, Maik Hauschild, Ilario Fulco, Christoph Tausch, Thomas Fischer, Dimitri Sarlos, Mihai Constantinescu, Judith E Lupatsch, Florian Fitzal, Joerg Heil, Zoltán Mátrai, Jana de Boniface, Christian Kurzeder, Martin Haug, Alexandra Schulz. Pre- versus sub-pectoral implant-based breast reconstruction after skin-sparing mastectomy or nipple-sparing mastectomy (OPBC-02 PREPEC): A pragmatic, multicenter, randomized, superiority trial [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr OT-23-03.

Abstract PD4-04: Tailored axillary surgery to omit axillary lymph node dissection independently from the use of neoadjuvant chemotherapy in patients with clinically node-positive breast cancer: Pre-specified subproject within TAXIS (SAKK 23/16 / IBCSG 57-18 / ABCSG-53 / GBG 101)

Introduction: We developed tailored axillary surgery (TAS) to selectively remove positive nodes and omit axillary lymph node dissection (ALND) in patients with clinically node-positive breast cancer irrespective of the use of neoadjuvant chemotherapy. In this study, we evaluate the performance of this novel surgical concept that tailors the extent of axillary surgery to the extent of axillary disease. Methods: A prospective study was pre-specified to assess the performance of TAS in the international multicenter phase-III TAXIS trial randomizing patients with clinically node-positive breast cancer to undergo ALND or axillary radiation after TAS. TAS consists of selective removal of all palpably suspicious findings and the SLNs followed by specimen radiography to document removal of the clip placed in the sampled node. Imaging-guided localization is encouraged to increase the chances of clip removal. Only patients with confirmed nodal disease at the time of surgery can be randomized in TAXIS; the first 200 randomized patients were analyzed together with the ones achieving nodal pCR in this study. ClinicalTrials.gov Identifier: NCT03513614. Results: A total of 296 patients with a median age of 56.5 years (range: 25-88 years) were included at 28 breast centers from four European countries, 125 (42.3%) of whom underwent NACT and 75 (25.3%) of whom had nodal pCR. Subtype was hormone receptor (HR) positive (+) and human epidermal growth factor receptor 2 (HER2) negative (-) in 194 (65.5%), HR+/HER2+ in 40 (13.5%), HR-/HER2+ in 17 (5.7%) and HR-/HER2- in 39 (13.2%) patients. Breast-conserving surgery was performed in 178 patients (60%) and mastectomy in 117 (40%). Imaging-guided localization was attempted in 258 patients (87.2%) and was successful in 243 (82.1%). TAS removed a median of two (interquartile range [IQR] 0-3) palpably suspicious lesions and two (IQR 1-3) SLNs, thereby successfully removing the clip in 279 (94.3%) patients. There were no significant differences by use of imaging-guided localization (94.6% with vs 92.1% without, p=0.47) or type of clip (p=0.19), but a trend toward lower rate of clip removal after NACT (91.2% with vs 96.5% without NACT, p=0.075). Palpable disease was left behind after TAS in two (2.1%) patients and no SLN was detected in three (3.1%). In the 200 randomized patients with confirmed nodal disease at the time of surgery, lymph node metastases were palpable at the time of initial diagnosis in 102 (51%) patients and detectable only by imaging in 98 (49%). The median number of lymph nodes removed by TAS was four (IQR 2-8), two (IQR 1-4) of which were positive. Completion ALND following TAS removed additional positive nodes in 71 of 100 (71%) patients in the control group (20% with one additional node, 9% with 2, 8% with 3, 6% with 4, and 28% with &gt;4). The median number of additional lymph nodes removed by ALND was 14 (IQR 10-18), two (IQR 0-6) of which were positive. Of the 200 randomized patients, one in the TAS group received a radiotherapy boost and one in the ALND group returned to the operating room for residual suspicious findings on imaging. Discussion: The present results suggest that TAS has the potential to become the new axillary surgery standard in patients with clinically node-positive breast cancer. TAS was successfully performed in the vast majority of patients, with no further improvement by imaging-guided localization, which makes the procedure feasible at most breast centers. TAS selectively removed positive lymph nodes and was much less radical than ALND, but ALND removed additional positive nodes in more than two thirds of patients. Disease-free survival and quality of life will be assessed in the randomized trial.

Citation Format: Walter Paul Weber, Guido Henke, Stefanie Hayoz, Karin Ribi, Stefanie Seiler, Charlotte Maddox, Thomas Ruhstaller, Daniel Rudolf Zwahlen, Simone Muenst, Markus Ackerknecht, Florian Fitzal, Mihály Újhelyi, Christian Kurzeder, Loïc Lelièvre, Christoph Tausch, Daniel Egle, Jörg Heil, Zoltan Matrai, Michael Knauer. Tailored axillary surgery to omit axillary lymph node dissection independently from the use of neoadjuvant chemotherapy in patients with clinically node-positive breast cancer: Pre-specified subproject within TAXIS (SAKK 23/16 / IBCSG 57-18 / ABCSG-53 / GBG 101) [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PD4-04.

Breast conservation and axillary management after primary systemic therapy in patients with early-stage breast cancer: the Lucerne toolbox

Primary systemic therapy is increasingly used in the treatment of patients with early-stage breast cancer, but few guidelines specifically address optimal locoregional therapies. Therefore, we established an international consortium to discuss clinical evidence and to provide expert advice on technical management of patients with early-stage breast cancer. The steering committee prepared six working packages to address all major clinical questions from diagnosis to surgery. During a consensus meeting that included members from European scientific oncology societies, clinical trial groups, and patient advocates, statements were discussed and voted on. A consensus was reached in 42% of statements, a majority in 38%, and no decision in 21%. Based on these findings, the panel developed clinical guidance recommendations and a toolbox to overcome many clinical and technical requirements associated with the diagnosis, response assessment, surgical planning, and surgery of patients with early-stage breast cancer. This guidance could convince clinicians and patients of the major clinical advancements purported by primary systemic therapy, the use of less extensive and more targeted surgery to improve the lives of patients with breast cancer.

Renal Infarcts-A Perplexing Case in the Middle of the COVID-19 Pandemic

Renal infarction is a rare finding in children. Associations between SARS-CoV-2 infections and thromboembolic events including renal infarcts have been described in adults. Although a similar association in children has not yet been described with this pandemic, the pediatric literature is still evolving with the recognition of new manifestations including the post-infectious Multisystem Inflammatory Syndrome in Children (MIS-C). We report the rare event of multiple renal infarcts in a 6-year-old boy manifesting several features of MIS-C 9 weeks following a self-limiting febrile illness characteristic of COVID-19. An underlying Factor V Leiden mutation was identified in this child but felt to be insufficient on its own to explain his clinical presentation. As SARS-CoV-2 testing was delayed, the failure to identify viral RNA or antibodies may not exclude the virus' potential role in precipitating the infarct in this host. Given that renal infarcts have been described in adult patients with COVID-19, reporting this perplexing case where SARS-CoV-2 may have played a role, may help identify this potential complication.

Prognostic Value of EndoPredict in Women with Hormone Receptor-Positive, HER2-Negative Invasive Lobular Breast Cancer

PURPOSE

Invasive lobular carcinoma (ILC) accounts for approximately 5%-15% of all invasive breast cancer cases. Most of the correlations between multigene assays and patient outcome were derived from studies based on patients with invasive ductal carcinoma (IDC) or without distinction between the subtypes. Here, we investigate the prognostic value of EndoPredict (EPclin) in a large cohort of ILCs pooled from three phase III randomized trials (ABCSG-6, ABCSG-8, TransATAC).

EXPERIMENTAL DESIGN

The primary objective of this analysis was to determine the prognostic value of EPclin for distant recurrence (DR) in years 0-10 in postmenopausal women with ILC. The primary outcome was DR.

RESULTS

470 women (17.9%) presented with ILC, 1,944 (73.9%) with IDC, and 216 (8.2%) with other histologic types. EPclin was highly prognostic in women with ILC [HR = 3.32 (2.54-4.34)] and provided more prognostic value than the Clinical Treatment Score [CTS; HR = 2.17 (1.73-2.72)]. 63.4% of women were categorized into the low EPclin risk group and they had a 10-year DR of 4.8% (2.7-8.4) compared with 36.6% of women in the high-risk group with a 10-year DR risk of 26.6% (20.0-35.0). EPclin also provided highly prognostic information in women with node-negative disease [HR = 2.56 (1.63-4.02)] and node-positive disease [HR = 3.70 (2.49-5.50)].

CONCLUSIONS

EPclin provided highly significant prognostic value and significant risk stratification for women with ILC. Ten-year DR risk in the EPclin low-risk groups were similar between ILC and IDC. Our results show that EPclin is informative in women with ILC and suggest that it is equally valid in both histologic subtypes.

Prospective randomized controlled trial on comparison of standard CO2 pressure pneumoperitoneum insufflator versus AirSeal®

Background

AirSeal® is a valve-free insufflation system that enables a stable pneumoperitoneum with continuous smoke evacuation and CO₂ recirculation during laparoscopic surgery. Comparative evidence on the use of AirSeal® and standard CO₂ insufflator in laparoscopic general surgery procedures is scarce. The aim of this study was to compare surgical outcomes between AirSeal® and standard CO₂ insufflators in patients undergoing the most frequently performed laparoscopic procedures.

Methods

One hundred and ninety-eight patients undergoing elective laparoscopic cholecystectomy, colorectal surgery and hernia repair were randomized to either AirSeal® (group A) or standard pressure CO₂ insufflator (group S). The primary endpoints were operative time and level of postoperative shoulder tip pain (Visual Analog Scale). Secondary outcomes included Clavien–Dindo grade complications, surgical side effect and length of hospital stay.

Results

Patients were randomized to either group A (n = 101) or group S (n = 97) and were analyzed by intention-to-treat. There was no significant difference in mean operative time between the groups (median [IQR]; 71 min [56–94] in group A vs. 69 min [52–93] in group S; p = 0.434). Shoulder tip pain levels were significantly lower in group S (VAS 0 [0–3] in group S vs. 2 [0–4] in group A; p = 0.001). There was no significant difference in complications, surgical side effects (subcutaneous emphysema was not observed in any group) and length of hospital stay.

Conclusion

This randomized controlled trial showed that using the AirSeal® system did not reduce operative time and was associated with a higher postoperative shoulder tip pain compared to standard CO₂ insufflator for short elective surgeries.

ClinicalTrials.gov (NCT01740011).

Primary surgery versus no surgery in synchronous metastatic breast cancer: patient-reported quality-of-life outcomes of the prospective randomized multicenter ABCSG-28 Posytive Trial

BACKGROUND

The ABCSG-28 trial compared primary surgery followed by systemic therapy versus primary systemic therapy without surgery in patients with de novo stage IV BC. The present report describes QoL results of this trial.

METHODS

Ninety patients with primary operable MBC were randomised to surgery of the primary tumor followed by systemic therapy or to primary systemic therapy without surgery. QoL analyses covering the results at baseline, 6,12,18 and 24 months follow up of 79 (88%) patients, was assessed with the EORTC QLQ-C30 and QLQ-BR23 questionnaires.

RESULTS

There were no statistically significant differences in any of the scales of the QLQ-C30 and QLQ-BR23 questionnaires between the two groups over the time. Baseline global health status and physical functioning were predictors for OS (patients with a higher score lived longer (p=0.0250, p=0.0225; p=0.0355, p=0.0355)). Global health status, social functioning scale, breast symptoms and future perspective were predictors for longer TTPd (p=0.0244; p=0.0140, p=0.020; p=0.0438, p=0.0123). Patients in both arms reported significant improvement on the emotional functioning scale. Cognitive functioning decreased over time in both groups. Younger women had clinically relevant better physical and sexual functioning scores (p=0.039 and 0.024).

CONCLUSION

Primary surgery does not improve nor alter QoL of patients with de novo stage IV BC. Global health status and physical functioning were predictors for OS and could be use as additional marker for prediction of OS and TTTd in patients with de novo stage IV BC.

TRIAL REGISTRATION

The trial is registered on clinicaltrial.gov (NCT01015625, date of registration:18/11/2009).

Do YOU know the Ki-67 index of your breast cancer patients? Knowledge of your institution's Ki-67 index distribution and its robustness is essential for decision-making in early breast cancer

Objectives

The proliferative activity of the Ki-67 index is important in decision-making of adjuvant treatments in early breast cancer. Its reliability can be reduced by inter-observer variability. This analysis’ objective is to evaluate the robustness of Ki-67 values within one center over 5 years and to compare its distribution with a published dataset.

Materials and methods

Ki-67 indices of early breast cancers treated at St. Gallen Breast Center were collected (2010–2014; 1154 patients). Distribution of Ki-67 values was analyzed for each year, along with histologic subtype and grading. Tumors were classified into intrinsic subtypes using two definitions: 2013 St. Gallen Consensus and the refined definition by Maisonneuve (“Milano Group”). Our institution’s Ki-67 cut-off value was adjusted to obtain the same distribution of luminal subtypes as published data of the Milano Group.

Results

Ki-67 index frequency distributions were comparable between years (mean 26–30%, median 22–26%). Shape and position of the distribution curves were nearly identical. Ki-67 values correlated with tumor grade (median Ki-67: G1: 12.0%, G2: 21%, G3: 38%). Standard deviation of Ki-67 increased with higher grading (G1: 6.9; G2: 9.2; G3: 18.2; p < 0.001). According to the 2013 definition (and refined definition respectively), there were 35% (41%) luminal A-like and 65% (59%) luminal B-like tumors. To obtain the same distribution as the Milano group, Ki-67 cut-off needed to be elevated to 22%.

Conclusions

Ki-67 index assessment was comparable over many years. Knowledge of one’s institution’s Ki-67 value distribution is essential for clinical decision-making of adjuvant therapies in early breast cancer.

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Limiting the number of observers can improve reproducibility of Ki-67 assessments.

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Comparison with published data-sets helps to define adequate Ki-67 cut-off levels.

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Lobular breast cancers have a significantly lower Ki-67 than ductal breast cancers.

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Ki-67 values and standard deviation increase parallel to increasing tumor grade.

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Ki-67, properly assessed, remains important for decision making in breast cancer.

Abstract P5-06-29: Prognosis of triple negative metastatic breast cancer (MBC): Results from the AGMT_MBC-Registry

Background: Triple-negative breast cancer (TNBC) comprises a heterogeneous group of diseases which are generally associated with poor prognosis. In recent years, major progress has been made in the treatment of metastatic breast cancer (MBC), especially for hormone receptor (HR) positive and HER2 positive MBC. In contrast, for most TNBC patients no targeted treatment options are available. Population-based data on overall survival (OS) of triple negative MBC are scarce and were totally missing for the Austrian population. Here, we present the overall survival (OS) results of triple-negative breast cancer patients included the MBC registry of the Austrian Study Group for Medical Tumor Therapy (AGMT). Patients and methods: The AGMT_MBC-Registry is a multicenter nationwide ongoing retrospective and prospective registry for MBC patients in Austria. Unadjusted, univariate survival probabilities of OS were calculated by the Kaplan-Meier method and multivariate hazard ratios (HR) were estimated by Cox regression models. In this analysis only patients with triple-negative MBC with available survival data were included. Results: As of 31/01/2019, 1,253 patients were included in the AGMT-MBC-Registry. Out of 1,219 evaluable patients with available survival data, 192 (17.8%) were triple-negative. Mean age at diagnosis of MBC was 59 (range 27-89), 44 patients (22.9%) were diagnosed with de novometastatic disease, 89 patients (46.4%) with metachronous MBC had a disease free survival (DFS) &lt; 24 months, 134 (69.8%) were treated with (neo)adjuvant therapy, 114 (59.4%) had visceral disease at diagnosis of MBC, and number of involved metastatic sites at diagnosis was 1 in 102 (53.1%), 2 in 49 (25.5%), 3 in 24 (12.5%) and &gt; 3 sites in 17 (8.9%) patients. Fifty-nine patients (49.5%) received at least one treatment-line which included bevacizumab. Bevacizuamb was combined with capecitabine, paclitaxel and gemcitabine in 38, 68 and 5 patients, respectively. Median OS of TNBC was 15.2 months (95% CI 11.4-18.9), compared to 32.9 months (95% CI 29.7-35.7) in the overall cohort. In multivariate analysis including established risk factors and clinically relevant variables, only three variables were significantly associated with OS in TNBC patients: disease free survival (&lt;24 months vs ≥ 24 months or de novo MBC: HR 1.80 [95% CI 1.29-2.51]), visceral disease (yes vs no: HR 1.75 [95% CI 1.22-2.52]), and number of metastatic sites at initial diagnosis (2-3 vs 1: HR 1.81 [95% CI 1.26-2.60], &gt; 3 vs 1: HR 3.05 [95% CI 1.66-5.61]). Conclusion: The poor prognosis of TNBC was confirmed in this population-based analysis. Besides known prognostic factors like de novo metastatic disease, DFS and visceral disease, the number of metastatic sites at initial diagnosis was identified as a novel independent prognostic factor in TNBC.

Citation Format: Gabriel Rinnerthaler, Simon P Gampenrieder, Andreas Petzer, Christoph Tinchon, David Fuchs, Marija Balic, Sonja Heibl, Holger Rumpold, Daniel Egle, August F Zabernigg, Christian F Singer, Johannes Andel, Michael Hubalek, Michael Knauer, Richard Greil. Prognosis of triple negative metastatic breast cancer (MBC): Results from the AGMT_MBC-Registry [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P5-06-29.

Abstract P3-08-29: Landscape of HER2-low metastatic breast cancer (MBC): Results from the AGMT-MBC-Registry

Background: About 50% of all primary breast cancers show a low-level expression of HER2 (HER2-low), defined as immunohistochemically 1+ or 2+ and lack of HER2 gene amplification measured by in-situ hybridization. This low HER2 expression is a promising new target for antibody-drug conjugates (ADCs) currently under development. Until now, little is known about the frequency and the prognostic value of low HER2-expression in metastatic breast cancer (MBC). Patients and methods: The MBC-Registry of the Austrian Study Group of Medical Tumor Therapy (AGMT) is a multicenter nationwide ongoing retrospective and prospective registry for MBC patients in Austria. Unadjusted, univariate survival probabilities of PFS and OS were calculated by the Kaplan-Meier method and compared by the log-rank test, multivariate hazard ratios (HR) were estimated by Cox regression models. In this analysis patients with known HER2 status and available survival data were included. Results: As of 31/01/2019, 1,253 patients were included in the AGMT-MBC-Registry. Out of 1,079 evaluable patients, 262 (24.3%) were HER2-positive, 372 (34.5%) were HER2-low and 445 (41.2%) were completely HER2-negative (HER2-0). The distribution of hormone receptor (HR) expression is shown in Table 1. Median OS and median first-line PFS for these three subgroups in dependency of HR expression is presented in Table 2. Neither in univariate (p=0.821) nor in multivariate analysis including HR status, disease-free survival (DFS), age and visceral disease (p=0.590, HR 1.06), low HER2 expression had a significant impact on prognosis compared to completely HER2-negative disease. Overall 13/372 (3.5%) of the HER2-low and 11/445 (2.5%) of the HER2-0 patients received anti-HER2 treatment. In the HER2+ cohort 200/262 (76.3%) were treated with trastuzumab, 106 (40.5%) with pertuzumab and 49 (18.7%) with T-DM1. In the HR+ subgroup, 11/162 (6.8%), 78/302 (25.8%) and 89/323 (27.6%) patients were treated with a CDK4/6 inhibitor in the HER2+, HER2-low and HER2-0 subgroup, respectively. Conclusion: Low-HER2 expression did not have any impact on prognosis or choice of treatment in metastatic breast cancer in this real-world population.

Table 1HER2-positive (IHC 3+ or ISH+)HER2-low (IHC1+ or 2+ and ISH-)completely HER2-negative (IHC 0)All (n=1,079)262 (24.3%)372 (34.5%)445 (41.2%)HR+ (n=787)162 (20.6%)302 (38.4%)323 (41.0%)HR- (n=292)100 (34.2%)70 (24.0%)122 (41.8%)

Table 2HER2+ months (95%CI)HER2-low months (95%CI)HER2-0 months (95%CI)Log-rankPMedian OSAll (n=1,079)42.7 (32.5-52.9)32.2 (27.3-37.1)30.8 (26.0-35.7)0.007HR+ (n=787)49.6 (40.1-59.1)35.8 (31.4-40.2)40.5 (35.4-45.5)0.120HR- (n=292)26.4 (19.9-33.0)16.8 (12.9-20.7)14.3 (10.0-18.6)&lt; 0.001Median 1st-line PFS All (n=913)*12.4 (10.1-14.8)11.0 (9.3-12.7)11.3 (9.6-12.9)0.123HR+ (n=684)*14.6 (10.8-18.4)12.4 (10.3-14.5)14.7 (12.1-17.4)0.348HR- (n=229)*11.0 (8.2-13.9)5.6 (3.9-7.2)6.0 (4.4-7.5)&lt; 0.001* only patients with at least one line of therapy for metastatic disease and sufficiently documented medical records allowing calculation of PFS were included.

Citation Format: Simon Peter Gampenrieder, Gabriel Rinnerthaler, Andreas Petzer, Christoph Tinchon, David Fuchs, Marija Balic, Sonja Heibl, Holger Rumpold, Daniel Egle, August Felix Zabernigg, Christian Fridolin Singer, Johannes Andel, Michael Hubalek, Michael Knauer, Richard Greil. Landscape of HER2-low metastatic breast cancer (MBC): Results from the AGMT-MBC-Registry [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P3-08-29.

Strong impact of MammaPrint and BluePrint on treatment decisions in luminal early breast cancer: results of the WSG-PRIMe study

PURPOSE

The WSG-PRIMe Study prospectively evaluated the impact of the 70-gene signature MammaPrint® (MP) and the 80-gene molecular subtyping assay BluePrint® on clinical therapy decisions in luminal early breast cancer.

METHODS

452 hormone receptor (HR)-positive and HER2-negative patients were recruited (N0, N1). Physicians provided initial therapy recommendations based on clinicopathological factors. After prospective risk classification by MammaPrint/BluePrint was revealed, post-test treatment recommendations and actual treatment were recorded. Decisional Conflict and anxiety were measured by questionnaires.

RESULTS

Post-test switch (in chemotherapy (CT) recommendation) occurred in 29.1% of cases. Overall, physician adherence to MP risk assessment was 92.3% for low-risk and 94.3% for high-risk MP scores. Adherence was remarkably high in "discordant" groups: 74.7% of physicians initially recommending CT switched to CT omission following low-risk MP scores; conversely, 88.9% of physicians initially recommending CT omission switched to CT recommendations following high-risk MP scores. Most patients (99.2%) recommended to forgo CT post-test and 21.3% of patients with post-test CT recommendations did not undergo CT; among MP low-risk patients with pre-test and post-test CT recommendations, 40% did not actually undergo CT. Luminal subtype assessment by BluePrint was discordant with IHC assessment in 34% of patients. Patients' State Anxiety scores improved significantly overall, particularly in MP low-risk patients. Trait Anxiety scores increased slightly in MP high risk and decreased slightly in MP low-risk patients.

CONCLUSIONS

MammaPrint and BluePrint test results strongly impacted physicians' therapy decisions in luminal EBC with up to three involved lymph nodes. The high adherence to genetically determined risk assessment represents a key prerequisite for achieving a personalized cost-effective approach to disease management of early breast cancer.

Tailored axillary surgery with or without axillary lymph node dissection followed by radiotherapy in patients with clinically node-positive breast cancer (TAXIS): study protocol for a multicenter, randomized phase-III trial

Background

Complete lymph node removal through conventional axillary dissection (ALND) has been standard treatment for breast cancer patients for almost a century. In the 1990s, however, and in parallel with the advent of the sentinel lymph node (SLN) procedure, ALND came under increasing scrutiny due to its association with significant patient morbidity. Several studies have since provided evidence to suggest omission of ALND, often in favor of axillary radiation, in selected clinically node-negative, SLN-positive patients, thus supporting the current trend in clinical practice. Clinically node-positive patients, by contrast, continue to undergo ALND in many cases, if only for the lack of studies re-assessing the indication for ALND in these patients. Hence, there is a need for a clinical trial to evaluate the optimal treatment for clinically node-positive breast cancer patients in terms of surgery and radiotherapy. The TAXIS trial is designed to fill this gap by examining in particular the value of tailored axillary surgery (TAS), a new technique for selectively removing positive lymph nodes.

Methods

In this international, multicenter, phase-III, non-inferiority, randomized controlled trial (RCT), including 34 study sites from four different countries, we plan to randomize 1500 patients to either receive TAS followed by ALND and regional nodal irradiation excluding the dissected axilla, or receive TAS followed by regional nodal irradiation including the full axilla. All patients undergo adjuvant whole-breast irradiation after breast-conserving surgery and chest-wall irradiation after mastectomy. The main objective of the trial is to test the hypothesis that treatment with TAS and axillary radiotherapy is non-inferior to ALND in terms of disease-free survival of clinically node-positive breast cancer patients in the era of effective systemic therapy and extended regional nodal irradiation. The trial was activated on 31 July 2018 and the first patient was randomized on 7 August 2018.

Discussion

Designed to test the hypothesis that TAS is non-inferior to ALND in terms of curing patients and preventing recurrences, yet is significantly superior in reducing patient morbidity, this trial may establish a new worldwide treatment standard in breast cancer surgery. If found to be non-inferior to standard treatment, TAS may significantly contribute to reduce morbidity in breast cancer patients by avoiding surgical overtreatment.

Trial registration

ClinicalTrials.gov, ID: NCT03513614. Registered on 1 May 2018.

www.kofam.ch, ID: NCT03513614. Registered on 17 June 2018.

EudraCT No.: 2018–000372-14.

Electronic supplementary material

The online version of this article (10.1186/s13063-018-3021-9) contains supplementary material, which is available to authorized users.

Second International Consensus Conference on lesions of uncertain malignant potential in the breast (B3 lesions)

Purpose

The second International Consensus Conference on B3 lesions was held in Zurich, Switzerland, in March 2018, organized by the International Breast Ultrasound School to re-evaluate the consensus recommendations.

Methods

This study (1) evaluated how management recommendations of the first Zurich Consensus Conference of 2016 on B3 lesions had influenced daily practice and (2) reviewed current literature towards recommendations to biopsy.

Results

In 2018, the consensus recommendations for management of B3 lesions remained almost unchanged: For flat epithelial atypia (FEA), classical lobular neoplasia (LN), papillary lesions (PL) and radial scars (RS) diagnosed on core-needle biopsy (CNB) or vacuum-assisted biopsy (VAB), excision by VAB in preference to open surgery, and for atypical ductal hyperplasia (ADH) and phyllodes tumors (PT) diagnosed at VAB or CNB, first-line open surgical excision (OE) with follow-up surveillance imaging for 5 years. Analyzing the Database of the Swiss Minimally Invasive Breast Biopsies (MIBB) with more than 30,000 procedures recorded, there was a significant increase in recommending more frequent surveillance of LN [65% in 2018 vs. 51% in 2016 (p = 0.004)], FEA (72% in 2018 vs. 62% in 2016 (p = 0.005)), and PL [(76% in 2018 vs. 70% in 2016 (p = 0.04)] diagnosed on VAB. A trend to more frequent surveillance was also noted also for RS [77% in 2018 vs. 67% in 2016 (p = 0.07)].

Conclusions

Minimally invasive management of B3 lesions (except ADH and PT) with VAB continues to be appropriate as an alternative to first-line OE in most cases, but with more frequent surveillance, especially for LN.

The influence of breast cancer subtypes on axillary ultrasound accuracy: A retrospective single center analysis of 583 women

INTRODUCTION

Axillary ultrasound staging (AUS) is an important tool to guide clinical decisions in breast cancer therapy, especially regarding axillary surgery but also radiation therapy. It is unknown whether biological subtypes influence axillary staging using ultrasound (AUS).

METHOD

This is a retrospective single center analysis. All patients with breast cancer, a preoperative axillary ultrasound and a complete surgical axillary staging were included between 1999 and 2014, except patients with neoadjuvant chemotherapy (NACT). The results of the AUS were compared with final pathological results. Biological subtypes were identified by immunohistochemistry.

RESULTS

583 women were included in the study. Sensitivity, Specificity, positive and negative predictive value for AUS were 39%, 96%, 91% and 83%. While sensitivity was significantly lower in Luminal A and B patients (25.0%; 39.8%) as compared to non Luminal breast cancer patients (TN 68.8%; Her2+ 71.4%; p = 0.0032), there were no significant differences between the groups with respect to specificity, PPV and NPV.

CONCLUSION

Solely regarding sensitivity of AUS, our study could show significant differences between biological subtypes of breast cancer with lower sensitivity in Luminal patients. While PPV was excellent, standing for a low overtreatment rate using AUS for clinical decision making, sensitivity was poor overall, comparable to the results of other studies.

Axillary dissection versus no axillary dissection in patients with breast cancer and sentinel-node micrometastases (IBCSG 23-01): 10-year follow-up of a randomised, controlled phase 3 trial

BACKGROUND

We previously reported the 5-year results of the phase 3 IBCSG 23-01 trial comparing disease-free survival in patients with breast cancer with one or more micrometastatic (≤2 mm) sentinel nodes randomly assigned to either axillary dissection or no axillary dissection. The results showed no difference in disease-free survival between the groups and showed non-inferiority of no axillary dissection relative to axillary dissection. The current analysis presents the results of the study after a median follow-up of 9·7 years (IQR 7·8-12·7).

METHODS

In this multicentre, randomised, controlled, open-label, non-inferiority, phase 3 trial, participants were recruited from 27 hospitals and cancer centres in nine countries. Eligible women could be of any age with clinical, mammographic, ultrasonographic, or pathological diagnosis of breast cancer with largest lesion diameter of 5 cm or smaller, and one or more metastatic sentinel nodes, all of which were 2 mm or smaller and with no extracapsular extension. Patients were randomly assigned (1:1) before surgery (mastectomy or breast-conserving surgery) to no axillary dissection or axillary dissection using permuted blocks generated by a web-based congruence algorithm, with stratification by centre and menopausal status. The protocol-specified primary endpoint was disease-free survival, analysed in the intention-to-treat population (as randomly assigned). Safety was assessed in all randomly assigned patients who received their allocated treatment (as treated). We did a one-sided test for non-inferiority of no axillary dissection by comparing the observed hazard ratios (HRs) for disease-free survival with a margin of 1·25. This 10-year follow-up analysis was not prespecified in the trial's protocol and thus was not adjusted for multiple, sequential testing. This trial is registered with ClinicalTrials.gov, number NCT00072293.

FINDINGS

Between April 1, 2001, and Feb 8, 2010, 6681 patients were screened and 934 randomly assigned to no axillary dissection (n=469) or axillary dissection (n=465). Three patients were ineligible and were excluded from the trial after randomisation. Disease-free survival at 10 years was 76·8% (95% CI 72·5-81·0) in the no axillary dissection group, compared with 74·9% (70·5-79·3) in the axillary dissection group (HR 0·85, 95% CI 0·65-1·11; log-rank p=0·24; p=0·0024 for non-inferiority). Long-term surgical complications included lymphoedema of any grade in 16 (4%) of 453 patients in the no axillary dissection group and 60 (13%) of 447 in the axillary dissection group, sensory neuropathy of any grade in 57 (13%) in the no axillary dissection group versus 85 (19%) in the axillary dissection group, and motor neuropathy of any grade (14 [3%] in the no axillary dissection group vs 40 [9%] in the axillary dissection group). One serious adverse event (postoperative infection and inflamed axilla requiring hospital admission) was attributed to axillary dissection; the event resolved without sequelae.

INTERPRETATION

The findings of the IBCSG 23-01 trial after a median follow-up of 9·7 years (IQR 7·8-12·7) corroborate those obtained at 5 years and are consistent with those of the 10-year follow-up analysis of the Z0011 trial. Together, these findings support the current practice of not doing an axillary dissection when the tumour burden in the sentinel nodes is minimal or moderate in patients with early breast cancer.

FUNDING

International Breast Cancer Study Group.

Impact of a Surgical Sealing Patch on Lymphatic Drainage After Axillary Dissection for Breast Cancer: The SAKK 23/13 Multicenter Randomized Phase III Trial

BACKGROUND

Several studies and a meta-analysis showed that fibrin sealant patches reduced lymphatic drainage after various lymphadenectomy procedures. Our goal was to investigate the impact of these patches on drainage after axillary dissection for breast cancer.

METHODS

In a phase III superiority trial, we randomized patients undergoing breast-conserving surgery at 14 Swiss sites to receive versus not receive three large TachoSil^® patches in the dissected axilla. Axillary drains were inserted in all patients. Patients and investigators assessing outcomes were blinded to group assignment. The primary endpoint was total volume of drainage.

RESULTS

Between March 2015 and December 2016, 142 patients were randomized (72 with TachoSil^® and 70 without). Mean total volume of drainage in the control group was 703 ml [95% confidence interval (CI) 512-895 ml]. Application of TachoSil^® did not significantly reduce the total volume of axillary drainage [mean difference (MD) -110 ml, 95% CI -316 to 94, p = 0.30]. A total of eight secondary endpoints related to drainage, morbidity, and quality of life were not improved by use of TachoSil^®. The mean total cost per patient did not differ significantly between the groups [34,253 Swiss Francs (95% CI 32,625-35,880) with TachoSil^® and 33,365 Swiss Francs (95% CI 31,771-34,961) without, p = 0.584]. In the TachoSil^® group, length of stay was longer (MD 1 day, 95% CI 0.3-1.7, p = 0.009), and improvement of pain was faster, although the latter difference was not significant [2 days (95% CI 1-4) vs. 5.5 days (95% CI 2-11); p = 0.2].

CONCLUSIONS

TachoSil^® reduced drainage after axillary dissection for breast cancer neither significantly nor relevantly.

The relationship between different measures of feed efficiency and feeding behavior traits in Duroc pigs

Utilization of feed in livestock species consists of a wide range of biological processes, and therefore, its efficiency can be expressed in various ways, including direct measurement, such as daily feed intake, as well as indicator measures, such as feeding behavior. Measuring feed efficiency is important to the swine industry, and its accuracy can be enhanced by using automated feeding systems, which record feed intake and associated feeding behavior of individual animals. Each automated feeder space is often shared among several pigs and therefore raises concerns about social interactions among pen mates with regard to feeding behavior. The study herein used a data set of 14,901 Duroc boars with individual records on feed intake, feeding behavior, and other off-test traits. These traits were modeled with and without the random spatial effect of Pen_Room, a concatenation of room and pen, or random social interaction among pen mates. The nonheritable spatial effect of common Pen-Room was observed for traits directly measuring feed intake and accounted for up to 13% of the total phenotypic variance in the average daily feeding rate. The social interaction effect explained larger proportions of phenotypic variation in all the traits studied, with the highest being 59% for ADFI in the group of feeding behaviors, 73% for residual feed intake (RFI; RFI4 and RFI6) in the feed efficiency traits, and 69% for intramuscular fat percentage in the off-test traits. After accounting for the social interaction effect, residual BW gain and RFI and BW gain (RIG) were found to have the heritability of 0.38 and 0.18, respectively, and had strong genetic correlations with growth and off-test traits. Feeding behavior traits were found to be moderately heritable, ranging from 0.14 (ADFI) to 0.52 (average daily occupation time), and some of them were strongly correlated with feed efficiency measures; for example, there was a genetic correlation of 0.88 between ADFI and RFI6. Our work suggested that accounting for the social common pen effect was important for estimating genetic parameters of traits recorded by the automated feeding system. Residual BW gain and RIG appeared to be two robust measures of feed efficiency. Feeding behavior measures are worth further investigation as indicators of feed efficiency.

Interleukin 7-expressing fibroblasts promote breast cancer growth through sustenance of tumor cell stemness

The tumor microenvironment harbors cancer-associated fibroblasts that function as major modulators of cancer progression. Here, we assessed to which extent distinct cancer-associated fibroblast subsets impact mammary carcinoma growth and cancer cell stemness in an orthotopic murine model. We found that fibroblasts expressing the Cre recombinase under the control of the interleukin 7 promoter occupied mainly the tumor margin where they physically interacted with tumor cells. Intratumoral ablation of interleukin 7-expressing fibroblasts impaired breast tumor growth and reduced the clonogenic potential of cancer cells. Moreover, cDNA expression profiling revealed a distinct oncogenic signature of interleukin 7-producing fibroblasts. In particular, Cxcl12 expression was strongly enhanced in interleukin 7-producing fibroblasts and cell type-specific genetic ablation and systemic pharmacological inhibition revealed that the CXCL12/CXCR4 axis impacts breast tumor cell stemness. Elevated expression of CXCL12 and other stem cell factors in primary human breast cancer-associated fibroblasts indicates that certain fibroblast populations support tumor cell stemness and thereby promote breast cancer growth.