Omission of Axillary Dissection Following Nodal Downstaging With Neoadjuvant Chemotherapy

Importance

Data on oncological outcomes after omission of axillary lymph node dissection (ALND) in patients with breast cancer that downstages from node positive to negative with neoadjuvant chemotherapy are sparse. Additionally, the best axillary surgical staging technique in this scenario is unknown.

Objective

To investigate oncological outcomes after sentinel lymph node biopsy (SLNB) with dual-tracer mapping or targeted axillary dissection (TAD), which combines SLNB with localization and retrieval of the clipped lymph node.

Design, Setting, and Participants

In this multicenter retrospective cohort study that was conducted at 25 centers in 11 countries, 1144 patients with consecutive stage II to III biopsy-proven node-positive breast cancer were included between April 2013 and December 2020. The cumulative incidence rates of axillary, locoregional, and any invasive (locoregional or distant) recurrence were determined by competing risk analysis.

Exposure

Omission of ALND after SLNB or TAD.

Main Outcomes and Measures

The primary end points were the 3-year and 5-year rates of any axillary recurrence. Secondary end points included locoregional recurrence, any invasive (locoregional and distant) recurrence, and the number of lymph nodes removed.

Results

A total of 1144 patients (median [IQR] age, 50 [41-59] years; 78 [6.8%] Asian, 105 [9.2%] Black, 102 [8.9%] Hispanic, and 816 [71.0%] White individuals; 666 SLNB [58.2%] and 478 TAD [41.8%]) were included. A total of 1060 patients (93%) had N1 disease, 619 (54%) had ERBB2 (formerly HER2)-positive illness, and 758 (66%) had a breast pathologic complete response. TAD patients were more likely to receive nodal radiation therapy (85% vs 78%; P = .01). The clipped node was successfully retrieved in 97% of TAD cases and 86% of SLNB cases (without localization). The mean (SD) number of sentinel lymph nodes retrieved was 3 (2) vs 4 (2) (P < .001), and the mean (SD) number of total lymph nodes removed was 3.95 (1.97) vs 4.44 (2.04) (P < .001) in the TAD and SLNB groups, respectively. The 5-year rates of any axillary, locoregional, and any invasive recurrence in the entire cohort were 1.0% (95% CI, 0.49%-2.0%), 2.7% (95% CI, 1.6%-4.1%), and 10% (95% CI, 8.3%-13%), respectively. The 3-year cumulative incidence of axillary recurrence did not differ between TAD and SLNB (0.5% vs 0.8%; P = .55).

Conclusions and Relevance

The results of this cohort study showed that axillary recurrence was rare in this setting and was not significantly lower after TAD vs SLNB. These results support omission of ALND in this population.

ERBB2-amplified lobular breast carcinoma exhibits concomitant CDK12 co-amplification associated with poor prognostic features

Most invasive lobular breast carcinomas (ILBCs) are luminal-type carcinomas with an HER2-negative phenotype (ERBB2 or HER2 un-amplified) and CDH1 mutations. Rare variants include ERBB2-amplified subtypes associated with an unfavorable prognosis and less response to anti-HER2 targeted therapies. We analyzed the clinicopathological and molecular features of ERBB2-amplified ILBC and compared these characteristics with ERBB2-unamplified ILBC. A total of 253 patients with ILBC were analyzed. Paraffin-embedded formalin-fixed tumor samples from 250 of these patients were added to a tissue microarray. Protein expression of prognostic, stem cell and breast-specific markers was tested by immunohistochemistry (IHC). Hybrid capture-based comprehensive genomic profiling (CGP) was performed for 10 ILBCs that were either fluorescent in situ hybridization (FISH) or IHC positive for HER2 amplification/overexpression and 10 ILBCs that were either FISH or IHC negative. Results were compared with a CGP database of 44,293 invasive breast carcinomas. The CGP definition of ERBB2 amplification was five copies or greater. A total of 17 of 255 ILBC (5%) were ERBB2 amplified. ERBB2-amplified ILBC had higher tumor stage (p < 0.0001), more frequent positive nodal status (p = 0.00022), more distant metastases (p = 0.012), and higher histological grade (p < 0.0001), and were more often hormone receptor negative (p < 0.001) and more often SOX10 positive (p = 0.005). ERBB2 short variant sequence mutations were more often detected in ERBB2-unamplified tumors (6/10, p = 0.027), whereas CDH1 mutations/copy loss were frequently present in both subgroups (9/10 and 7/10, respectively). Amplification of pathogenic genes were more common in HER2-positive ILBC (p = 0.0009). CDK12 gene amplification (≥6 copies) was detected in 7 of 10 ERBB2-amplified ILBC (p = 0.018). There were no CDK12 gene amplifications reported in 44,293 invasive breast carcinomas in the FMI Insights CGP database. ERBB2-amplified ILBC is a distinct molecular subgroup with frequent coamplification of CDK12, whereas ERBB2 sequence mutations occur only in ERBB2-unamplified ILBC. CDK12/ERBB2 co-amplification may explain the poor prognosis and therapy resistance of ERBB2-amplified ILBC.

Long-Term Follow-Up of High-Risk Breast Lesions at Vacuum-Assisted Biopsy without Subsequent Surgical Resection

Introduction

B3-lesions of the breast are a heterogeneous group of neoplasms, associated with a higher risk of breast cancer. Recent studies show a low upgrade rate into malignancy after subsequent open surgical excision (OE) of most B3-lesions when proven by vacuum-assisted biopsy (VAB). However, there is a lack of long-term follow-up data after VAB of high-risk lesions. The primary aim of this study was to demonstrate whether follow-up of B3 lesions is a beneficial and reliable alternative to OE in terms of long-term outcome. The secondary aim was to identify patient and lesion characteristics of B3 lesions for which OE is still necessary.

Methods

This retrospective multicenter study was conducted at 8 Swiss breast centers between 2010 and 2019. A total of 278 women (mean age: 53.5 ± 10.7 years) with 286 B3-lesions who had observation only and who had at least 24 months of follow-up were included. Any event during follow-up (ductal carcinoma in situ [DCIS], invasive cancer, new B3-lesion) was systematically recorded. Data from women who had an event during follow-up were compared with those who did not. The results for the different B3 lesions were analyzed using the t test and Fisher's exact test. A p value of <0.05 was considered statistically significant.

Results

The median follow-up interval was 59 months (range: 24-143 months) with 52% (148/286) having a follow-up of more than 5 years. During follow-up, in 42 women, 44 suspicious lesions occurred, with 36.4% (16/44) being invasive cancer and 6.8% (3/44) being DCIS. Thus, 6.6% (19/286) of all women developed malignancy during follow-up after a median follow-up interval of 6.5 years (range: 31-119 months). The initial histology of the B3 lesion influenced the subsequent occurrence of a malignant lesion during follow-up (p < 0.038). The highest malignancy-developing rate was observed in atypical ductal hyperplasia (ADH) (24%, 19/79), while all other B3-lesions had malignant findings ipsi- and contralateral between 0% and 6%. The results were not influenced by the VAB method (Mx-, US-, magnetic resonance imaging-guided), the radiological characteristics of the lesion, or the age or menopausal status of the patient (p > 0.12).

Conclusion

With a low risk of <6% of developing malignancy, VAB followed by long-term follow-up is a safe alternative to OE for most B3-lesions. A higher malignancy rate only occurred in ADH (24%). Based on our results, radiological follow-up should be bilateral, preferable using the technique of initial diagnosis. As we observed a late peak (6-7 years) of breast malignancies after B3-lesions, follow-up should be continued for a longer period (>10 years). Knowledge of these long-term outcome results will be helpful in making treatment decisions and determining the optimal radiological follow-up interval.

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.

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.

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

The heterogeneous group of B3 lesions in the breast harbors lesions with different malignant potential and progression risk. As several studies about B3 lesions have been published since the last Consensus in 2018, the 3rd International Consensus Conference discussed the six most relevant B3 lesions (atypical ductal hyperplasia (ADH), flat epithelial atypia (FEA), classical lobular neoplasia (LN), radial scar (RS), papillary lesions (PL) without atypia, and phyllodes tumors (PT)) and made recommendations for diagnostic and therapeutic approaches. Following a presentation of current data of each B3 lesion, the international and interdisciplinary panel of 33 specialists and key opinion leaders voted on the recommendations for further management after core-needle biopsy (CNB) and vacuum-assisted biopsy (VAB). In case of B3 lesion diagnosis on CNB, OE was recommended in ADH and PT, whereas in the other B3 lesions, vacuum-assisted excision was considered an equivalent alternative to OE. In ADH, most panelists (76%) recommended an open excision (OE) after diagnosis on VAB, whereas observation after a complete VAB-removal on imaging was accepted by 34%. In LN, the majority of the panel (90%) preferred observation following complete VAB-removal. Results were similar in RS (82%), PL (100%), and FEA (100%). In benign PT, a slim majority (55%) also recommended an observation after a complete VAB-removal. VAB with subsequent active surveillance can replace an open surgical intervention for most B3 lesions (RS, FEA, PL, PT, and LN). Compared to previous recommendations, there is an increasing trend to a de-escalating strategy in classical LN. Due to the higher risk of upgrade into malignancy, OE remains the preferred approach after the diagnosis of ADH.

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 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 GS4-02: Oncological Outcomes Following Omission of Axillary Lymph Node Dissection in Node Positive Patients Downstaging To Node Negative with Neoadjuvant Chemotherapy: the OPBC-04/EUBREAST-06/OMA study

Background: Data on the oncologic safety of omission of axillary lymph node dissection (ALND) in node positive (N+) patients who downstage to ypN0 with neoadjuvant chemotherapy (NAC) is sparse. Additionally, there is no consensus on which axillary staging procedure should be used in this setting, sentinel lymph node biopsy (SLNB) alone or in combination with localization and retrieval of the clipped positive node, also known as targeted axillary dissection (TAD). Whether the reduction in the false negative rate observed with TAD translates into a significant reduction in the rate of axillary recurrence is unknown. We sought to evaluate oncologic outcomes after omission of ALND in a large, real-world cohort of breast cancer (BC) patients and to compare rates of axillary recurrence after SLNB with dual tracer mapping vs. TAD.

Methods: Data were collected from 19 centers in the Oncoplastic Breast Consortium (OPBC) and EUBREAST networks. Patients with T1-4 biopsy-proven N1-3 BC who underwent NAC followed by axillary staging with either SLNB with dual tracer mapping or TAD and who were pathologically node negative (ypN0) were included. ypN0 was defined as the absence of any tumor or isolated tumor cells. Competing risk analysis was performed to assess the cumulative incidence rates of axillary recurrence, locoregional recurrence, and any invasive (locoregional or distant) recurrence. Two-year cumulative incidence rates were compared between TAD and SLNB using the Gray’s test. Type I error rate was set to 0.05 (α).

Results: We included 785 patients (565 treated with SLNB and 220 with TAD) treated with NAC followed by surgery from 01/2014-12/2020. Median patient age was 50 years. The majority (57%) of patients had clinical T2 tumors, and 95% had N1 disease. Most (55%) were HER2+, and 21% were triple negative. Most patients (81%) received anthracycline and taxane-based chemotherapy regimens, but NAC regimens differed between patients treated with TAD and those treated with SLNB (Table 1). All patients with HER2+ tumors received anti HER2 therapy. Nodal radiotherapy was administered to 76% of patients, and was more common in patients who underwent TAD (82% TAD vs 74% SLNB, p=0.017). Breast pathologic complete response (ypT0/is) was more frequent among those patients that had TAD (80% TAD vs. 66% SLNB, p&lt; 0.001). TAD localization was with wire in 46%, radioactive seed in 40%, ultrasound in 5%, tattoo in 2%, and with a combination of these techniques in 7%. The clipped node was successfully retrieved in 94% of TAD cases. The median number of lymph nodes removed was lower in the TAD group compared to the SLNB group [3 (IQR 3-5) vs 4 IQR 3-5), p&lt; 0.001], as was the median number of sentinel lymph nodes [3 (IQR 2-4) vs 4 IQR 3-5), p&lt; 0.001] (Table 1). The 5-year rates of any axillary recurrence, locoregional recurrence, and any invasive recurrence in the entire cohort were 1.1% (95%CI 0.39-2.4%), 3.1% (95%CI 1.6-5.3%) and 10% (95%CI 7.6-13%), respectively. The two-year cumulative incidence of axillary recurrence did not differ between patients treated with TAD compared to SLNB (0% vs 0.9%, p=0.19).

Conclusion: Early axillary recurrence after omission of ALND in patients who successfully downstage from N+ to ypN0 with NAC is a rare event following both SLNB or TAD, and was not significantly lower in TAD than SLNB. Although longer follow-up is needed to confirm these findings, the main advantage of TAD seems to be a reduction in the number of lymph nodes removed. Overall, these results support omission of ALND in patients who successfully downstage to node negative disease after NAC.

Table 1: Clinicopathological Features of the Study Cohort, Stratified by Axillary Staging Technique

Citation Format: Giacomo Montagna, Mary Mrdutt, Astrid Botty, Andrea V. Barrio, Varadan Sevilimedu, Judy C. Boughey, Tanya L. Hoskin, Laura H. Rosenberger, E Shelley Hwang, Abigail Ingham, Bärbel Papassotiropoulos, Bich Doan Nguyen-Sträuli, Christian Kurzeder, Danilo Diaz Aybar, Denise Vorburger, Dieter Michael Matlac, Edvin Ostapenko, Fabian Riedel, Florian Fitzal, Francesco Meani, Franziska Fick, Jacqueline Sagasser, Jörg Heil, Konstantin J. Dedes, Laszlo Romics, Maggie Banys-Paluchowski, Maria Del Rosario Cueva Perez, Marcelo Chavez Diaz, Martin Heidinger, Mathias K. Fehr, Mattea Reinisch, Nadia Maggi, Nicola Rocco, Nina Ditsch, Oreste Davide Gentilini, Regis Resende Paulinelli, Sebastian Sole Zarhi, Sherko Küemmel, Simona Bruzas, Simona Di Lascio, Tamara Parissenti, Uwe Güth, Valentina Ovalle, Christoph Tausch, Monica Morrow, Thorsten Kühn, Walter P. Weber. Oncological Outcomes Following Omission of Axillary Lymph Node Dissection in Node Positive Patients Downstaging To Node Negative with Neoadjuvant Chemotherapy: the OPBC-04/EUBREAST-06/OMA study [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 GS4-02.

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

•

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.

Factors Indicating Surgical Excision in Classical Type of Lobular Neoplasia of the Breast

PURPOSE

Classical type of lobular neoplasia (LN) encompassing both atypical lobular hyperplasia and classical lobular carcinoma in situ of the breast is a lesion with uncertain malignant potential and has been the topic of several studies with conflicting outcome results. The aim of our study was to clarify outcome-relevant factors and treatment options of classical LN.

METHODS

We performed a pathological re-evaluation of the preoperative biopsy specimens and a retrospective clinical and radiological data analysis of 160 patients with LN from the Breast Center Zurich. Open surgery was performed in 65 patients, vacuum-assisted biopsy (VAB) in 79 patients, and surveillance after breast core needle biopsy (CNB) in 16 patients.

RESULTS

The upgrade rate into ductal carcinoma in situ/invasive cancer was the highest in case of imaging/histology discordance (40%). If the number of foci in the biopsy specimen was ≥3, the upgrade rate in the consecutive surgical specimens was increased (p = 0.01). The association of classical LN with histological microcalcification correlated with shortened disease-free survival (p < 0.01), whereas other factors showed no impact on follow-up.

CONCLUSIONS

Surveillance or subsequent VAB after CNB of LN is sufficient in most cases. Careful consideration of individual radiological and histological factors is required to identify patients with a high risk of upgrade into malignancy. In those cases, surgical excision is indicated.

Retrospective, Multicenter Analysis Comparing Conventional with Oncoplastic Breast Conserving Surgery: Oncological and Surgical Outcomes in Women with High-Risk Breast Cancer from the OPBC-01/iTOP2 Study

Introduction

Recent data suggest that margins ≥2 mm after breast-conserving surgery may improve local control in invasive breast cancer (BC). By allowing large resection volumes, oncoplastic breast-conserving surgery (OBCII; Clough level II/Tübingen 5-6) may achieve better local control than conventional breast conserving surgery (BCS; Tübingen 1-2) or oncoplastic breast conservation with low resection volumes (OBCI; Clough level I/Tübingen 3-4).

Methods

Data from consecutive high-risk BC patients treated in 15 centers from the Oncoplastic Breast Consortium (OPBC) network, between January 2010 and December 2013, were retrospectively reviewed.

Results

A total of 3,177 women were included, 30% of whom were treated with OBC (OBCI n = 663; OBCII n = 297). The BCS/OBCI group had significantly smaller tumors and smaller resection margins compared with OBCII (pT1: 50% vs. 37%, p = 0.002; proportion with margin <1 mm: 17% vs. 6%, p < 0.001). There were significantly more re-excisions due to R1 (“ink on tumor”) in the BCS/OBCI compared with the OBCII group (11% vs. 7%, p = 0.049). Univariate and multivariable regression analysis adjusted for tumor biology, tumor size, radiotherapy, and systemic treatment demonstrated no differences in local, regional, or distant recurrence-free or overall survival between the two groups.

Conclusions

Large resection volumes in oncoplastic surgery increases the distance from cancer cells to the margin of the specimen and reduces reexcision rates significantly. With OBCII larger tumors are resected with similar local, regional and distant recurrence-free as well as overall survival rates as BCS/OBCI.

Supplementary information

The online version contains supplementary material available at 10.1245/s10434-021-10809-1.

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.

•

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

•

Tailored axillary surgery selectively removes positive lymph nodes

•

Tailored axillary surgery is much less radical than axillary dissection

•

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.

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.

Correction to: Comparative analysis of confocal microscopy on fresh breast core needle biopsies and conventional histology

Following publication of the original article [1], the authors reported an added data on Table 1 in their paper. The original article [1] has been updated.

Comparative analysis of confocal microscopy on fresh breast core needle biopsies and conventional histology

Background

Evaluation of core needle biopsies (CNB) is a standard procedure for the diagnosis of breast cancer. However, tissue processing and image preparation is a time- consuming procedure and instant on-site availability of high-quality images could substantially improve the efficacy of the diagnostic procedure. Conventional microscopic methods, such as frozen section analysis (FSA) for detection of malignant cells still have clear disadvantages. In the present study, we tested a confocal microscopy scanner on fresh tissue from CNB with intention to develop an alternative device to FSA in clinical practice.

Patients and methods

In 24 patients with suspicious breast lesions standard of care image-guided biopsies were performed. Confocal images have been obtained using the Histolog™ Scanner and evaluated by two independent pathologists. Hematoxylin-Eosin (H&E) histological sections of the biopsies were routinely processed in a blinded fashion with respect to the confocal images.

Results

In total 42 confocal images were generated from 24 biopsy specimens, and available for analysis within a few minutes of taking the biopsy. This resulted in 2 × 42 = 84 pathologic evaluations. In four cases, a pathologic diagnosis was not possible with confocal microscopy. An exact correlation based on the B-classification was reached in 41 out of 80 examinations and in another 35 cases in a broader sense of correspondence definition (i.e. malignant vs. benign).

Conclusions

As a reliable on-site method, the Histolog™ Scanner provides a visualization of cellular details equivalent to the H&E standards, permitting rapid and accurate diagnosis of malignant and benign breast lesions. Furthermore, this device offers great potential for immediate margin analysis of specimen in breast conserving therapy.

The impact of distinct triple-negative breast cancer subtypes on misdiagnosis and diagnostic delay

BACKGROUND

Triple-negative breast cancer (TNBC) includes mostly aggressive types of breast cancer with poor prognosis. Due to its growth pattern, misinterpretation in clinical imaging is more frequent than in non-TNBC. As the group of TNBC contains heterogeneous types of tumors, marker expression-based subtypes have recently been established. We analyzed clinical features and false-negative imaging findings that could potentially lead to diagnostic delay within the subtypes.

METHODS

An exploratory analysis compared the imaging features across the a priori defined subtypes and related these findings to molecular subtype, disease stage, potential diagnostic delay, and patient outcome.

RESULTS

TNBC cases were categorized into basal-like (BL; 38.6%), mesenchymal-like (ML; 19.9%), luminal androgen receptor (LAR; 28.3%), and immunomodulatory (IM; 13.3%) subtype. In almost every third patient, malignant classification was missed in at least one imaging method. Misclassification in mammogram was more frequent in ML, while benign ultrasound features were reported more often in the BL subtype. Diagnostic delay due to misclassification in imaging led to tumor growth and/or upgrading of the tumor stage in 8.9% of BL tumors, which had the lowest overall survivals. Despite misclassification rate was higher in the ML subtype it showed better outcomes. Misdiagnosis of axillary lymph node metastasis was higher in LAR; however, this subtype showed a higher percentage of affected axillary lymph nodes.

CONCLUSION

TNBC subtypes have different clinical features, benign appearances, and diagnostic delay, which can lead to tumor stage upgrade. Future clinical studies on TNBC outcomes might consider the confounder of clinical delay in the subtypes.

Prospective Evaluation of Residual Breast Tissue After Skin- or Nipple-Sparing Mastectomy: Results of the SKINI-Trial

OBJECTIVE

This study was designed to investigate the presence of residual breast tissue (RBT) after skin-sparing mastectomy (SSM) and nipple-sparing mastectomy (NSM) and to analyse patient- and therapy-related factors associated with RBT. Skin-sparing mastectomy and NSM are increasingly used surgical procedures. Prospective data on the completeness of breast tissue resection is lacking. However, such data are crucial for assessing oncologic safety of risk-reducing and curative mastectomies.

METHODS

Between April 2016 and August 2017, 99 SSM and 61 NSM were performed according to the SKINI-trial protocol, under either curative (n = 109) or risk-reducing (n = 51) indication. After breast removal, biopsies from the skin envelope (10 biopsies per SSM, 14 biopsies per NSM) were taken in predefined radial localizations and assessed histologically for the presence of RBT and of residual disease.

RESULTS

Residual breast tissue was detected in 82 (51.3%) mastectomies. The median RBT percentage per breast was 7.1%. Of all factors considered, only type of surgery (40.4% for SSM vs. 68.9% for NSM; P < 0.001) and surgeon (P < 0.001) were significantly associated with RBT. None of the remaining factors, e.g., skin flap necrosis, was associated significantly with RBT. Residual disease was detected in three biopsies.

CONCLUSIONS

Residual breast tissue is commonly observed after SSM and NSM. In contrast, invasive or in situ carcinomas are rarely found in the skin envelope. Radicality of mastectomy in this trial is not associated with increased incidence of skin flap necrosis. ClinicalTrials.gov Identifier NCT03470909.

Abstract P3-03-24: ABCSG 33 - A multi center registry to evaluate the affect of macro metastasis in sentinel lymph node on survival

Background:

Sentinel lymph node dissection identifies nodal positivity in early breast cancer. Trials like the ACOSOG Z0011 trial tried to show that the waiver of axillary dissection in nodal positive breast cancer (BC) has no effect on the oncologic outome, however real world data are rare and the role of adjuvant regional radiotherapy is still disputed in this respect.

Objective:

We initiated a multicenter observational registry to investigate omission of axillary lymph node dissection in nodal positive early BC.

Design and Setting:

The 18 sites participating in Austria and Switzerland included from 2014 to 2017 178 patients in this trail.

Patients:

Women with unilateral invasive lymph node positive BC with one or two sentinel lymph node makrometastases, who did not undergo axillary lymph node dissection were included.

Results:

We had a median follow up time of 3.1 years (range between 0.5 and 10.5 years), the median patient age is 63.6 years (range between 33 – 93 years). In 16.9% women had a G1 Grading, 53.1% had G2 tumor and 29.9% had a G3 tumor. Multifocality was seen in 18.1% of the patients. Luminal A tumors were seen in 16 (8.9%) and Luminal B in 82 (46.1%). Fourteen (7.8%) patients in this cohort had HER2 positive BC. In one (0.5%) local recurrence of the axilla occurred. Three (1.7%) of 178 patients died due to BC recurrence.

Conclusion:

Patients with macro metastasis in the sentinel lymph node, treated with breast conserving surgery and whole breast radiation did not have an increased risk of BC recurrence.

Therefore the authors assume that axillary dissection in patients with early stage BC and macro metastasis is not necessary in this patient cohort.

Citation Format: Strobl SA, Dubsky P, Exner R, Gnant M, Jakesz R, Tausch C, Wette V, Heck D, Luisser I, Bjelic-Radisic V, Schrenk P, Poyssl C, Mathis J, Fitzal F. ABCSG 33 - A multi center registry to evaluate the affect of macro metastasis in sentinel lymph node on survival [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P3-03-24.

Atypical ductal hyperplasia and the risk of underestimation: tissue sampling method, multifocality, and associated calcification significantly influence the diagnostic upgrade rate based on subsequent surgical specimens

Background

Risk assessment and therapeutic options are challenges when counselling patients with an atypical ductal hyperplasia (ADH) to undergo either open surgery or follow-up only.

Methods

We retrospectively analyzed a series of ADH lesions and assessed whether the morphological parameters of the biopsy materials indicated whether the patient should undergo surgery. A total of 207 breast biopsies [56 core needle biopsies (CNBs) and 151 vacuum-assisted biopsies (VABs)] histologically diagnosed as ADH were analyzed retrospectively, together with subsequently obtained surgical specimens. All histological slides were re-analyzed with regard to the presence/absence of ADH-associated calcification, other B3 lesions (lesion of uncertain malignant potential), extent of the lesion, and the presence of multifocality.

Results

The overall underestimation rate for the whole cohort was 39% (57% for CNB, 33% for VAB). In the univariate analysis, the method of biopsy (CNB vs VAB, p = 0.002) and presence of multifocality in VAB specimens (p = 0.0176) were significant risk factors for the underestimation of the disease (ductal carcinoma in situ or invasive cancer detected on subsequent open biopsy). In the multivariate logistic regression model, the absence of calcification (p = 0.0252) and the presence of multifocality (unifocal vs multifocal ADH, p = 0.0147) in VAB specimens were significant risk factors for underestimation.

Conclusions

Multifocal ADH without associated calcification diagnosed by CNB tends to have a higher upgrade rate. Because the upgrade rate was 16.5% even in the group with the lowest risk (VAB-diagnosed unifocal ADH with calcification), we could not identify a subgroup that would not require an open biopsy.

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.

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.

Impact of pretreatment thrombocytosis on survival in primary breast cancer

Platelet count has been reported to have predictive value in various cancer entities. In the case of breast cancer, evidence about involvement of platelets is still incomplete. Our objective was to assess the influence of pretreatment thrombocytosis on survival and establish its prognostic relevance for breast cancer patients.

We performed a retrospective, multivariate analysis of 4,300 patients with early-stage breast cancer. All subjects participated in one of five prospective, randomized, multicenter trials conducted by the Austrian Breast and Colorectal Cancer Study Group. Thrombocytosis was defined as a platelet count exceeding 400 G/L. Median follow-up was 52 months. Univariate and multiple Cox regression models were calculated for overall survival (OS), breast cancer-related survival and disease-free survival (DFS). Pretreatment thrombocytosis was observed in 161 patients (3.7%). Estimated median OS, breast cancer-related survival and DFS for patients with versus those without thrombocytosis was 71.0 versus 99.5, 72.0 versus 100.9, and 80.4 versus 88.4 months, respectively (p = 0.0054, p = 0.0095, p = 0.0199). A multiple Cox regression model including tumor and nodal status, grading, age, hormone receptor status and pretreatment thrombocytosis identified pretreatment thrombocytosis as an independent predictive factor for OS (p = 0.0064) and breast cancer-related survival (p = 0.0162). Multivariate analysis failed to identify pretreatment thrombocytosis as an independent risk factor for DFS (p = 0.1355).

In our retrospective study, elevated platelet counts at time of diagnosis were associated with poor prognosis in breast cancer. We hypothesize that platelets may contribute to the patho-physiology of hematogenous metastasis.

Adjuvant treatment recommendations for patients with ER-positive/HER2-negative early breast cancer by Swiss tumor boards using the 21-gene recurrence score (SAKK 26/10)

Background

To evaluate the effect of Recurrence Score® results (RS; Oncotype DX® multigene assay ODX) on treatment recommendations by Swiss multidisciplinary tumor boards (TB).

Methods

SAKK 26/10 is a multicenter, prospective cohort study of early breast cancer patients: Eligibility: R0-resection, ≥10% ER+ malignant cells, HER2–, pN0/pN1a. Patients were stratified into low-risk (LR) and non-low-risk (NLR) groups based on involved nodes (0 vs 1–3) and five additional predefined risk factors. Recommendations were classified as hormonal therapy (HT) or chemotherapy plus HT (CT + HT). Investigators were blinded to the statistical analysis plan. A 5%/10% rate of recommendation change in LR/NLR groups, respectively, was assumed independently of RS (null hypotheses).

Results

Two hundred twenty two evaluable patients from 18 centers had TB recommendations before and after consideration of the RS result. A recommendation change occurred in 45 patients (23/154 (15%, 95% CI 10–22%) in the LR group and 22/68 (32%, 95% CI 22–45%) in the NLR group). In both groups the null hypothesis could be rejected (both p < 0.001). Specifically, in the LR group, only 5/113 (4%, 95% CI 1–10%) with HT had a recommendation change to CT + HT after consideration of the RS, while 18/41 (44%, 95% CI 28–60%) of patients initially recommended CT + HT were subsequently recommended only HT. In the NLR group, 3/19 (16%, 95% CI 3–40%) patients were changed from HT to CT + HT, while 19/48 (40%, 95% CI 26–55%) were changed from CT + HT to HT.

Conclusion

There was a significant impact of using the RS in the LR and the NLR group but only 4% of LR patients initially considered for HT had a recommendation change (RC); therefore these patients could forgo ODX testing. A RC was more likely for NLR patients considered for HT. Patients considered for HT + CT have the highest likelihood of a RC based on RS.

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

The purpose of this study is to obtain a consensus for the therapy of B3 lesions. The first International Consensus Conference on lesions of uncertain malignant potential in the breast (B3 lesions) including atypical ductal hyperplasia (ADH), flat epithelial atypia (FEA), classical lobular neoplasia (LN), papillary lesions (PL), benign phyllodes tumors (PT), and radial scars (RS) took place in January 2016 in Zurich, Switzerland organized by the International Breast Ultrasound School and the Swiss Minimally Invasive Breast Biopsy group-a subgroup of the Swiss Society of Senology. Consensus recommendations for the management and follow-up surveillance of these B3 lesions were developed and areas of research priorities were identified. The consensus recommendation for FEA, LN, PL, and RS diagnosed on core needle biopsy or vacuum-assisted biopsy (VAB) is to therapeutically excise the lesion seen on imaging by VAB and no longer by open surgery, with follow-up surveillance imaging for 5 years. The consensus recommendation for ADH and PT is, with some exceptions, therapeutic first-line open surgical excision. Minimally invasive management of selected B3 lesions with therapeutic VAB is acceptable as an alternative to first-line surgical excision.

Patients' preferences for subcutaneous trastuzumab versus conventional intravenous infusion for the adjuvant treatment of HER2-positive early breast cancer: final analysis of 488 patients in the international, randomized, two-cohort PrefHer study

BACKGROUND

Patients with HER2-positive early breast cancer (EBC) preferred subcutaneous (s.c.) trastuzumab, delivered via single-use injection device (SID), over the intravenous (i.v.) formulation (Cohort 1 of the PrefHer study: NCT01401166). Here, we report patient preference, healthcare professional satisfaction, and safety data pooled from Cohort 1 and also Cohort 2, where s.c. trastuzumab was delivered via hand-held syringe.

PATIENTS AND METHODS

Patients were randomized to receive four adjuvant cycles of 600 mg fixed-dose s.c. trastuzumab followed by four cycles of standard i.v. trastuzumab, or vice versa. The primary endpoint was overall preference proportions for s.c. or i.v., assessed by patient interviews in the evaluable ITT population.

RESULTS

A total of 245 patients were randomized to receive s.c. followed by i.v. and 243 received i.v. followed by s.c. (evaluable ITT populations: 235 and 232 patients, respectively). s.c. was preferred by 415/467 [88.9%; 95% confidence interval (CI) 85.7-91.6; P < 0.0001; two-sided test against null hypothesis of 65% s.c. preference]; 45/467 preferred i.v. (9.6%; 95% CI 7-13); 7/467 indicated no preference (1.5%; 95% CI 1-3). Clinician-reported adverse events occurred in 292/479 (61.0%) and 245/478 (51.3%) patients during the pooled s.c. and i.v. periods, respectively (P < 0.05; 2 × 2 χ(2)); 16 patients (3.3%) in each period experienced grade 3 events; none were grade 4/5.

CONCLUSIONS

PrefHer revealed compelling and consistent patient preferences for s.c. over i.v. trastuzumab, regardless of SID or hand-held syringe delivery. s.c. was well tolerated and safety was consistent with previous reports, including the HannaH study (NCT00950300). No new safety signals were identified compared with the known i.v. profile in EBC. PrefHer and HannaH confirm that s.c. trastuzumab is a validated and preferred option over i.v. for improving patients' care in HER2-positive breast cancer.

CLINICALTRIALSGOV REGISTRATION NUMBER

NCT01401166.

Evaluating the predictive value of biomarkers for efficacy outcomes in response to pertuzumab- and trastuzumab-based therapy: an exploratory analysis of the TRYPHAENA study

INTRODUCTION

Molecular markers that predict responses to particular therapies are invaluable for optimization of patient treatment. The TRYPHAENA study showed that pertuzumab and trastuzumab with chemotherapy was an efficacious and tolerable combination for patients with human epidermal growth factor receptor 2 (HER2)-positive breast cancer in the neoadjuvant setting. We analyzed whether particular biomarkers correlated with the responses observed and therefore may predict outcomes in patients given pertuzumab plus trastuzumab.

METHODS

We describe the analysis of a panel of biomarkers including HER2, human epidermal growth factor receptor 3 (HER3), epidermal growth factor receptor (EGFR), phosphatase and tensin homolog (PTEN), and phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA) by qRT-PCR, immunohistochemistry (IHC), fluorescence in situ hybridization (FISH), enzyme-linked immunosorbent assay (ELISA), and PCR-based mutational analyses as appropriate. For each marker analyzed, patients were categorized into 'low' (generally below median) or 'high' (generally above median) subgroups at baseline and post-treatment.

RESULTS

Correlation of marker subgroups with the achievement of a pathological complete response (pCR) (ypT0/is) was analyzed. HER2 protein and mRNA expression levels were associated with pCR rate in two of the three study arms and the pooled analyses. Correlations of biomarker status with pCR occurred in one individual arm only and the pooled analyses with EGFR and PTEN; however, interpretation of these results is limited by a strong imbalance in patient numbers between the high and low subgroups and inconsistency between arms. We also found no association between expression levels of TOP2A and pCR rate in either the anthracycline-containing or free arms of TRYPHAENA.

CONCLUSIONS

According to these analyses, and in line with other analyses of pertuzumab and trastuzumab in the neoadjuvant setting, we conclude that HER2 expression remains the only marker suitable for patient selection for this regimen at present.

TRIAL REGISTRATION

The TRYPHAENA study was registered with ClinicalTrials.gov, NCT00976989, on September 14 2009.

Mapping lymph nodes in cancer management - role of (99m)Tc-tilmanocept injection

Two decades ago, lymphatic mapping of sentinel lymph nodes (SLN) was introduced into surgical cancer management and was termed sentinel node navigated surgery. Although this technique is now routinely performed in the management of breast cancer and malignant melanoma, it is still under investigation for use in other cancers. The radioisotope technetium (^99mTc) and vital blue dyes are among the most widely used enhancers for SLN mapping, although near-infrared fluorescence imaging of indocyanine green is also becoming more commonly used. ^99mTc-tilmanocept is a new synthetic radioisotope with a relatively small molecular size that was specifically developed for lymphatic mapping. Because of its small size, ^99mTc-tilmanocept quickly migrates from its site of injection and rapidly accumulates in the SLN. The mannose moieties of ^99mTc-tilmanosept facilitate its binding to mannose receptors (CD206) expressed in reticuloendothelial cells of the SLN. This binding prevents transit to second-echelon lymph nodes. In Phase III trials of breast cancer and malignant melanoma, and Phase II trials of other malignancies, ^99mTc-tilmanocept had superior identification rates and sensitivity compared with blue dye. Trials comparing ^99mTc-tilmanocept with other ^99mTc-based agents are required before it can be routinely used in clinical settings.

CYP2D6 phenotype indicative for optimized antiestrogen efficacy associates with outcome in early breast cancer patients

BACKGROUND

Endoxifen serum concentrations seem to correlate with outcome in breast cancer (BC) patients. Concurrently, cytochrome P450 2D6 (CYP2D6) enzyme activity and dextromethorphan (DM) metabolism are deemed a surrogate marker for the formation of endoxifen. Here, we conducted a matched cohort study to determine the impact of an extensive CYP2D6 phenotype on relapse in patients with early-stage estrogen receptor (ER)-positive BC and adjuvant tamoxifen intake.

METHODS

CYP2D6 extensive metabolism was determined upon appropriate dextromethorphan/dextrorphan (DM/DX) urinary excretion ratios (≤0.30). Fifty-nine BC patients were identified as extensive phenotype metabolizers, while for 148 matched controls, CYP2D6 was not determined. Patients and controls did not differ with respect to age, stage, hormone receptor status, HER2, grade, menopausal status, chemotherapy and antihormonal therapy. Survival analysis was performed according to clinical follow-up.

RESULTS

Disease-free survival (DFS) of patients identified as extensive CYP2D6 metabolizers did not differ significantly from controls (p = 0.10). However, when patients with ER expression of ≤ 20 % were excluded from the analysis, DFS was associated with a more favorable outcome (p = 0.06).

CONCLUSIONS

This study suggests a positive association between extensive CYP2D6 metabolism and outcome in early-stage ER-positive BC patients using tamoxifen and in particular, when a sufficient number ERs are represented on the primary tumor.

Tamoxifen and anastrozole as a sequencing strategy: a randomized controlled trial in postmenopausal patients with endocrine-responsive early breast cancer from the Austrian Breast and Colorectal Cancer Study Group

PURPOSE

Anastrozole (ANA) alone delivers significant disease-free survival benefits over tamoxifen (TAM) monotherapy in postmenopausal women with early estrogen receptor-positive breast cancer. The ABCSG-8 (Austrian Breast and Colorectal Cancer Study Group 8) study is a large phase III clinical trial addressing the sequence strategy containing ANA in comparison with 5 years of TAM in a low- to intermediate-risk group of postmenopausal patients.

PATIENTS AND METHODS

Endocrine receptor-positive patients with G1 or G2 tumors were eligible. After surgery, patients were randomly assigned to 5 years of TAM or 2 years of TAM followed by 3 years of ANA. Adjuvant chemotherapy and G3 and T4 tumors were exclusion criteria. Intention-to-treat and censored analyses of on-treatment recurrence-free survival (RFS) were performed, and exploratory survival end points and toxicity were investigated.

RESULTS

Information from 3,714 patients, including 17,563 woman-years, with a median of 60 months of follow-up was available for this analysis. Median age was 63.8 years, 75% were node negative, and 75% had T1 tumors. Sequencing of ANA after identical 2-year treatment with TAM in both arms did not result in a statistically significant improvement of RFS (hazard ratio [HR], 0.80; 95% CI, 0.63 to 1.01; P = .06). Exploratory analyses of distant relapse-free survival indicated a 22% improvement (HR, 0.78; 95% CI, 0.60 to 1.00). On-treatment adverse events and serious adverse events were consistent with known toxicity profiles of ANA and TAM treatment.

CONCLUSION

Despite a low overall rate of recurrence in a population with breast cancer at limited risk of relapse, the a priori sequence strategy of 2 years of TAM followed by 3 years of ANA led to small outcome and toxicity benefits.

Prognostic value of number of removed lymph nodes, number of involved lymph nodes, and lymph node ratio in 7502 breast cancer patients enrolled onto trials of the Austrian Breast and Colorectal Cancer Study Group (ABCSG)

PURPOSE

The number of removed axillary lymph nodes and the ratio of involved to removed lymph nodes are described as independent prognostic factors beside the absolute number of involved lymph nodes in breast cancer patients. The correlation between these factors and prognosis were investigated in trials of the Austrian Breast and Colorectal Cancer Study Group (ABCSG).

METHODS

This retrospective analysis is based on the data of 7052 patients with endocrine-responsive breast cancer who were randomized in four trials of the ABCSG in the years 1990-2006 and underwent axillary lymph node dissection. The prognostic value of number of removed nodes (NRN), number of involved nodes (NIN), and ratio of involved to removed nodes (lymph node ratio, LNR) concerning recurrence-free survival and overall survival was analyzed.

RESULTS

A total of 2718 patients had node-positive disease. No correlation was found between NRN and prognosis. Increasing NIN and LNR were significantly associated with worse recurrence-free survival and overall survival in univariate and multivariate analyses (P < .001). Only in the subgroup of patients with one to three positive lymph nodes and treated with mastectomy (n = 728) was LNR an additional prognostic factor in univariate and multivariate analyses.

CONCLUSIONS

For breast cancer patients stringently medicated in the framework of prospective adjuvant clinical trials and requiring a mandatory minimum of removed nodes, NRN does not influence prognosis, and LNR is not superior to NIN as prognostic factor. In patients with one to three positive lymph nodes and mastectomy, LNR could play a role as an additional prognostic factor.