Real-world use of multigene signatures in early breast cancer: differences to clinical trials

PURPOSE

In Italy, Lombardy was the first region to reimburse multigene assays (MGAs) for patients otherwise candidates for chemotherapy. This is a real-world experience of MGAs usage in six referral cancer centers in Lombardy.

METHODS

Among MGAs, Oncotype DX (RS) was used in 97% of cases. Consecutive patients tested with Oncotype DX from July 2020 to July 2022 were selected. The distribution of clinicopathologic features by RS groups (low RS: 0-25, high RS: 26-100) was assessed using chi-square and compared with those of the TAILORx and RxPONDER trials.

RESULTS

Out of 1,098 patients identified, 73% had low RS. Grade and Ki67 were associated with RS (p < 0.001). In patients with both G3 and Ki67 > 30%, 39% had low RS, while in patients with both G1 and Ki67 < 20%, 7% had high RS. The proportion of low RS in node-positive patients was similar to that in RxPONDER (82% vs 83%), while node-negative patients with low RS were significantly less than in TAILORx (66% vs 86%, p < 0.001). The distribution of Grade was different from registration trials, with more G3 and fewer G1 (38% and 3%) than in TAILORx (18% and 27%) and RxPONDER (10% and 24%) (p < 0.001). Patients ≤ 50 years were overrepresented in this series (41%) than in TAILORx and RxPONDER (31% and 24%, respectively) (p < 0.001) and, among them, 42% were node positive.

CONCLUSIONS

In this real-world series, Oncotype DX was the test almost exclusively used. Despite reimbursement being linked to pre-test chemotherapy recommendation, almost 3/4 patients resulted in the low-RS group. The significant proportion of node-positive patients ≤ 50 years tested indicates that oncologists considered Oncotype DX informative also in this population.

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.

Third national surgical consensus conference of the Italian Association of Breast Surgeons (ANISC) on management after neoadjuvant chemotherapy: The difficulty in reaching a consensus

INTRODUCTION

Neoadjuvant chemotherapy (NAC) has a profound impact on surgical management of breast cancer. For this reason, the Italian Association of Breast Surgeons (ANISC) promoted the third national Consensus Conference on this subject, open to multidisciplinary specialists.

MATERIALS AND METHODS

The Consensus Conference was held on-line in November 2022, and after an introductory session with five core-team experts, participants were asked to vote on eleven controversial issues, while results were collected in real-time with a polling system.

RESULTS

A total of 164 dedicated specialists from 74 Breast Centers participated. Consensus was reached for only three of the eleven issues, including: 1) the indication to assess the response with Magnetic Resonance Imaging (79 %); 2) the need to re-assess the biological factors of the residual tumor if present (96 %); 3) the possibility of omitting a formal axillary node dissection for cN1 patients if a pathologic Complete Response (pCR) was confirmed with analysis of one or more sentinel lymph nodes (82 %). The majority voted in favor of mapping both the breast and nodal lesions pre-NAC (59 %), and against the omission of sentinel lymph node biopsy in cN0 patients in the case of pathologic or clinical Complete Response (69 %). In cases of cT3/cN1+ tumors with pCR, only 8 % of participants considered appropriate the omission of Post-Mastectomy Radiation Therapy.

CONCLUSION

There is still a wide variability in surgical approaches after NAC in the "real world". As NAC is increasingly used, multidisciplinary teams should be attuned to conforming their procedures to the rapid advances in this field.

Applicability of magnetic seeds for target lymph node biopsy after neoadjuvant chemotherapy in initially node-positive breast cancer patients: data from the AXSANA study

PURPOSE

Currently, various techniques are available to mark and selectively remove initially suspicious axillary lymph nodes (target lymph nodes, TLNs) in breast cancer patients receiving neoadjuvant chemotherapy (NACT). To date, limited data are available on whether the use of magnetic seeds (MS) is suitable for localizing TLNs. This study aimed to investigate the feasibility of MS in patients undergoing target lymph node biopsy (TLNB) or targeted axillary dissection (TAD) after NACT.

METHODS

Prospective data from the ongoing multicentric AXSANA study were extracted from selected patients in whom the TLN had been marked with an MS before NACT and who were enrolled from June 2020 to June 2023. The endpoints of the analysis were the detection rate, the rate of lost markers, and the potential impairment on magnetic resonance imaging (MRI) assessment.

RESULTS

In 187 patients from 27 study sites in seven countries, MS were placed into the TLN before NACT. In 151 of these, post-NACT surgery had been completed at the time of analysis. In 146 patients (96.0%), a TLN could successfully be detected. In three patients, the seed was removed but no lymphoid tissue was detected on histopathology. The rate of lost markers was 1.2% (2 out of 164 MS). In 15 out of 151 patients (9.9%), MRI assessment was reported to be compromised by MS placement.

CONCLUSION

MS show excellent applicability for TLNB/TAD when inserted before NACT with a high DR and a low rate of lost markers. Axillary MS can impair MRI assessment of the breast.

TRIAL REGISTRATION NUMBER

NCT04373655 (date of registration May 4, 2020).

Sentinel Lymph Node Biopsy vs No Axillary Surgery in Patients With Small Breast Cancer and Negative Results on Ultrasonography of Axillary Lymph Nodes: The SOUND Randomized Clinical Trial

Importance

Sentinel lymph node biopsy (SLNB) is the standard of care for axillary node staging of patients with early breast cancer (BC), but its necessity can be questioned since surgery for examination of axillary nodes is not performed with curative intent.

Objective

To determine whether the omission of axillary surgery is noninferior to SLNB in patients with small BC and a negative result on preoperative axillary lymph node ultrasonography.

Design, Setting, and Participants

The SOUND (Sentinel Node vs Observation After Axillary Ultra-Sound) trial was a prospective noninferiority phase 3 randomized clinical trial conducted in Italy, Switzerland, Spain, and Chile. A total of 1463 women of any age with BC up to 2 cm and a negative preoperative axillary ultrasonography result were enrolled and randomized between February 6, 2012, and June 30, 2017. Of those, 1405 were included in the intention-to-treat analysis. Data were analyzed from October 10, 2022, to January 13, 2023.

Intervention

Eligible patients were randomized on a 1:1 ratio to receive SLNB (SLNB group) or no axillary surgery (no axillary surgery group).

Main Outcomes and Measures

The primary end point of the study was distant disease-free survival (DDFS) at 5 years, analyzed as intention to treat. Secondary end points were the cumulative incidence of distant recurrences, the cumulative incidence of axillary recurrences, DFS, overall survival (OS), and the adjuvant treatment recommendations.

Results

Among 1405 women (median [IQR] age, 60 [52-68] years) included in the intention-to-treat analysis, 708 were randomized to the SLNB group, and 697 were randomized to the no axillary surgery group. Overall, the median (IQR) tumor size was 1.1 (0.8-1.5) cm, and 1234 patients (87.8%) had estrogen receptor-positive ERBB2 (formerly HER2 or HER2/neu), nonoverexpressing BC. In the SLNB group, 97 patients (13.7%) had positive axillary nodes. The median (IQR) follow-up for disease assessment was 5.7 (5.0-6.8) years in the SLNB group and 5.7 (5.0-6.6) years in the no axillary surgery group. Five-year distant DDFS was 97.7% in the SLNB group and 98.0% in the no axillary surgery group (log-rank P = .67; hazard ratio, 0.84; 90% CI, 0.45-1.54; noninferiority P = .02). A total of 12 (1.7%) locoregional relapses, 13 (1.8%) distant metastases, and 21 (3.0%) deaths were observed in the SLNB group, and 11 (1.6%) locoregional relapses, 14 (2.0%) distant metastases, and 18 (2.6%) deaths were observed in the no axillary surgery group.

Conclusions and Relevance

In this randomized clinical trial, omission of axillary surgery was noninferior to SLNB in patients with small BC and a negative result on ultrasonography of the axillary lymph nodes. These results suggest that patients with these features can be safely spared any axillary surgery whenever the lack of pathological information does not affect the postoperative treatment plan.

Trial Registration

ClinicalTrials.gov Identifier: NCT02167490.

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.

Oncotype DX results increase concordance in adjuvant chemotherapy recommendations for early-stage breast cancer

Adjuvant chemotherapy recommendations for ER+/HER2- early-stage breast cancers (eBC) involve integrating prognostic and predictive information which rely on physician judgment; this can lead to discordant recommendations. In this study we aim to evaluate whether Oncotype DX improves confidence and agreement among oncologists in adjuvant chemotherapy recommendations. We randomly select 30 patients with ER+/HER2- eBC and recurrence score (RS) available from an institutional database. We ask 16 breast oncologists with varying years of clinical practice in Italy and the US to provide recommendation for the addition of chemotherapy to endocrine therapy and their degree of confidence in the recommendation twice; first, based on clinicopathologic features only (pre-RS), and then with RS result (post-RS). Pre-RS, the average rate of chemotherapy recommendation is 50.8% and is higher among junior (62% vs 44%; p < 0.001), but similar by country. Oncologists are uncertain in 39% of cases and recommendations are discordant in 27% of cases (interobserver agreement K 0.47). Post-RS, 30% of physicians change recommendation, uncertainty in recommendation decreases to 5.6%, and discordance decreases to 7% (interobserver agreement K 0.85). Interpretation of clinicopathologic features alone to recommend adjuvant chemotherapy results in 1 out of 4 discordant recommendations and relatively high physician uncertainty. Oncotype DX results decrease discordancy to 1 out of 15, and reduce physician uncertainty. Genomic assay results reduce subjectivity in adjuvant chemotherapy recommendations for ER +/HER2- eBC.

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.

Real de-escalation or escalation in disguise?

The past two decades have seen an unprecedented trend towards de-escalation of surgical therapy in the setting of early BC, the most prominent examples being the reduction of re-excision rates for close surgical margins after breast-conserving surgery and replacing axillary lymph node dissection by less radical procedures such as sentinel lymph node biopsy (SLNB). Numerous studies confirmed that reducing the extent of surgery in the upfront surgery setting does not impact locoregional recurrences and overall outcome. In the setting of primary systemic treatment, there is an increased use of less invasive staging strategies reaching from SLNB and targeted lymph node biopsy (TLNB) to targeted axillary dissection (TAD). Omission of any axillary surgery in the presence of pathological complete response in the breast is currently being investigated in clinical trials. On the other hand, concerns have been raised that surgical de-escalation might induce an escalation of other treatment modalities such as radiation therapy. Since most trials on surgical de-escalation did not include standardized protocols for adjuvant radiotherapy, it remains unclear, whether the effect of surgical de-escalation was valid in itself or if radiotherapy compensated for the decreased surgical extent. Uncertainties in scientific evidence may therefore lead to escalation of radiotherapy in some settings of surgical de-escalation. Further, the increasing rate of mastectomies including contralateral procedures in patients without genetic risk is alarming. Future studies of locoregional treatment strategies need to include an interdisciplinary approach to integrate de-escalation approaches combining surgery and radiotherapy in a way that promotes optimal quality of life and shared decision-making.

Abstract OT1-07-01: Omission of SLNB in triple-negative and HER2-positive breast cancer patients with radiologic and pathologic complete response in the breast after NAST: a single-arm, prospective surgical trial (EUBREAST-01 trial, GBG 104)

Background: Currently, axillary surgery for breast cancer is considered a staging procedure that does not seem to influence breast cancer mortality since the risk of developing metastasis depends mainly on the biological behavior of the primary (seed-and-soil model). Based on this, postsurgical therapy should be considered based on biological tumor characteristics. Retrospective data of cancer registry trials showed a strong correlation between breast pathologic complete response (pCR) and nodal pCR depending on intrinsic subtypes. Improvements in systemic treatments for breast cancer have increased the rates of pCR in patients receiving neoadjuvant systemic therapy (NAST), offering the opportunity to decrease, and perhaps eliminate, surgery in patients who have a pCR. Trial design: The EUBREAST network designed a clinical trial (NCT04101851) in which only patients with the highest likelihood of having a pCR after NAST (triple-negative or HER2-positive breast cancer) will be included, and type of surgery will be defined according to the response to NAST rather than on the classical T and N status at presentation. In the ongoing trial, axillary surgery will be eliminated (no axillary sentinel lymph node biopsy [SLNB]) for initially clinical node-negative (cN0) patients with radiologic complete remission (rCR) and a breast pCR (ypT0/ypTis) as determined in the lumpectomy specimen. The trial design is a multicenter single-arm study with a limited number of patients (N=440 as the screening population with an expected 80% pCR-rate) which might give practice-changing results in a short period, sparing the time and the costs of a randomized comparison. Patients will be recruited in European countries (Austria, Germany, Italy, and Spain) over 36 months. Inclusion criteria: -Written informed consent -Histologically confirmed unilateral primary invasive carcinoma of the breast (core biopsy). Multifocal or multicentric tumors are allowed if breast-conserving surgery (BCS) is planned. -Age at diagnosis at least 18 years -imaging techniques with estimated tumor stage between cT1-T3 before NAST -triple-negative (TNBC) or HER2-positive invasive breast cancer -TNBC is defined by: ER-negative (&lt; 10% positive cells in IHC) and PgR-negative (&lt; 10% positive cells in IHC), HER2-negative -clinically and sonographically tumor-free axilla before core biopsy (cN0/iN0) -in cases with cN0 and iN+, a negative core biopsy or fine-needle aspiration biopsy of the sonographically suspected lymph node is required -no evidence for distant metastasis (M0) -standard NAST with rCR -planned BCS with postoperative external whole-breast irradiation (conventional fractionation or hypofractionation) Primary objective: 3-year rate of axillary recurrence-free survival (ARFS) after BCS Statistics: The calculated total case number for per-protocol analysis is N=350, and the expected total number of screened patients is N=440. The assumption for acceptable 3-year ARFS ≥98.5% in the experimental arm is based on previous study findings. Timelines: -First patient in: January 2021 -Last patient in: December 2023 -Primary outcome analysis: Q1/2027 Current accrual: In June 2022, 150 patients were recruited in Germany and Italy. Contact: Prof. Dr. Toralf Reimer (eubreast-01@kliniksued-rostock.de), study chair Dr. Oreste D. Gentilini (gentilini.oreste@hsr.it), study co-chair Funding by Else Kroener-Fresenius Foundation, German Society of Senology, University of Rostock (Germany), and San Raffaele Hospital (Milan, Italy)

Citation Format: Toralf Reimer, Thorsten Kuehn, Angrit Stachs, Anke Kleine-Tebbe, Nikola Bangemann, Andrea Stefek, Carolin Hammerle, Jörg Heil, Antje Nixdorf, Gabriele Bonatz, Agnieszka Nolte, Isabel T. Rubio, Florentia Peintinger, Keyur Mehta, Sibylle Loibl, Edoardo Botteri, Oreste Davide Gentilini. Omission of SLNB in triple-negative and HER2-positive breast cancer patients with radiologic and pathologic complete response in the breast after NAST: a single-arm, prospective surgical trial (EUBREAST-01 trial, GBG 104) [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 OT1-07-01.

Abstract OT3-12-01: Immunological predictors of nodal response in breast cancer patients undergoing neoadjuvant therapy

Immunological predictors of nodal response in breast cancer patients undergoing neoadjuvant therapy Maria Luisa Gasparri1, Ilary Ruscito2, Filippo Bellati2, Fabio Corsi3, Rosa Di Micco4, Oreste D. Gentilini4, Thorsten Kuehn5, Andrea Papadia1, Donatella Caserta2, Lorenzo Rossi6, Arianna Calcinotto7 1 Department of Gynecology and Obstetrics, Ente Ospedaliero Cantonale, Ospedale Regionale di Lugano, Lugano, Switzerland 2 Department of Medical and Surgical Science and Translational Medicine, Sapienza University of Rome, Azienda Ospedaliera Sant’Andrea, Rome, Italy 3 Breast Unit, Department of Surgery, Istituti Clinici Scientifici Maugeri IRCCS, Pavia, Italy; Department of Biomedical and Clinical Sciences "Luigi Sacco", Università di Milano, Milan, Italy 4 Breast Surgery Unit, San Raffaele University Hospital, Milan, Italy 5 Interdisciplinary Breast Center, Department of Gynecology and Obstetrics, Klinikum Esslingen, Esslingen, Germany 6 Oncology Institute of Southern Switzerland, Bellinzona, Switzerland 7 Cancer Immunotherapy lab, IOR Institute of Oncology Research, Bellinzona, Switzerland Background: Almost 20% of breast cancer patients present at diagnosis with clinically positive nodes. Most of these patients undergo neoadjuvant therapy in order to de-escalate the axillary surgery in case of response (sentinel lymph node biopsy, targeted axillary dissection or targeted axillary dissection, instead of an axillary lymphadenectomy). The conversion from positive to negative nodes after neoadjuvant therpy is expected in approximately the 60% of the cases, depending by tumor subtypes. Several models have been proposed with the goal of identifying predictors of nodal response prior to neoadjuvant treatment. The immune system plays a pivotal role in cancer invasion and progression. Its role in treatment response is currently under investigation in several settings. Primary endpoint: to identify a preoperative immune profiling of breast cancer patients with nodal involvement at diagnosis and to correlate the immune changes after neoadjuvant therapy with the nodal response (macrometastases, micrometastasis, isolated tumor cells, complete response). Trial design: It is an international prospective cohort study including breast cancer patients undergoing standard neoadjuvant therapy, who present initially with biopsy-proven axillary lymph node metastasis. Ten immune markers will be analyzed using immunohistochemistry and tissue microarray in primary tumor and nodal tissue samples (tumor associated neutrophils, CD4 lymphocytes, CD8 lymphocytes, T regulatory cells, Macrophages, Follicular dendritic cells(DC), plasmocytoid DC, interdigitant DC, mature DC, Lysosomal associated membrane protein 3). The tissue analysis will be performed on the biopsy collected at diagnosis (prior to neoadjuvant therapy) and during the axillary surgery (after neoadjuvant therapy). Target accrual/sample size: 210 patients Statistical analysis: To compare the distribution of immune cells according to the state of lymph node metastasis, Student’s t test will be performed. Pearson’s chi-square test will be used to evaluate the correlation between immune profile and nodal response, based on clinic-pathological features. Odds ratios (ORs) and 95% confidence intervals (CIs) will be calculated using logistic regression analysis. Multivariable analysis will be performed using the multivariable logistic regression model. Logistic regression models will be used to identify the clinical, pathologic and immunological variables associated with the nodal response. P-values less than 0.05 will be considered significant. Analyses will be performed using Microsoft IBM SPSS® version 20.0 for Mac. Current status: Recruitment has not started yet. Contact information: marialuisa.gasparri@eoc.ch

Citation Format: Maria Luisa Gasparri, Ilary Ruscito, Filippo Bellati, Fabio Corsi, Rosa Di Micco, Oreste Davide Gentilini, Thorsten Kuehn, Andrea Papadia, Donatella Caserta, Lorenzo Rossi, Arianna Calcinotto. Immunological predictors of nodal response in breast cancer patients undergoing neoadjuvant therapy [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 OT3-12-01.

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.

Localization Techniques for Non-Palpable Breast Lesions: Current Status, Knowledge Gaps, and Rationale for the MELODY Study (EUBREAST-4/iBRA-NET, NCT 05559411)

BACKGROUND

Surgical excision of a non-palpable breast lesion requires a localization step. Among available techniques, wire-guided localization (WGL) is most commonly used. Other techniques (radioactive, magnetic, radar or radiofrequency-based, and intraoperative ultrasound) have been developed in the last two decades with the aim of improving outcomes and logistics.

METHODS

We performed a systematic review on localization techniques for non-palpable breast cancer.

RESULTS

For most techniques, oncological outcomes such as lesion identification and clear margin rate seem either comparable with or better than for WGL, but evidence is limited to small cohort studies for some of the devices. Intraoperative ultrasound is associated with significantly higher negative margin rates in meta-analyses of randomized clinical trials (RCTs). Radioactive techniques were studied in several RCTs and are non-inferior to WGL. Smaller studies show higher patient preference towards wire-free localization, but little is known about surgeons' and radiologists' attitudes towards these techniques.

CONCLUSIONS

Large studies with an additional focus on patient, surgeon, and radiologist preference are necessary. This review aims to present the rationale for the MELODY (NCT05559411) study and to enable standardization of outcome measures for future studies.

Current trends in diagnostic and therapeutic management of the axilla in breast cancer patients receiving neoadjuvant therapy: results of the German-wide NOGGO MONITOR 24 survey

PURPOSE

In the last 2 decades, the optimal management of the axilla in breast cancer patients receiving neoadjuvant chemotherapy (NACT) has been one of the most frequently discussed topics. Little is known about the attitudes of surgeons/radiologists towards new developments such as targeted axillary dissection. Therefore, the NOGGO conducted a survey to evaluate the current approach to axillary management.

METHODS

A standardized digital questionnaire was sent out to > 200 departments in Germany between 7/2021 and 5/2022. The survey was supported by EUBREAST.

RESULTS

In total, 116 physicians completed the survey. In cN0 patients scheduled to receive NACT, 89% of respondents recommended sentinel lymph node biopsy (SLNB) after NACT. In case of ypN1mi(sn), 44% advised no further therapy, while 31% proposed ALND and 25% axillary irradiation. 64% of respondents recommended a minimally invasive axillary biopsy to cN + patients. TAD was used at the departments of 82% of respondents and was offered to all cN + patients converting to ycN0 by 57% and only to selected patients, usually based on the number of suspicious nodes at time of presentation, by 43%. The most common marking technique was a clip/coil. 67% estimated that the detection rate of their marker was very good or good.

CONCLUSION

This survey shows a heterogenous approach towards axillary management in the neoadjuvant setting in Germany. Most respondents follow current guidelines. Since only two-thirds of respondents experienced the detection rate of the marker used at their department as (very) good, future studies should focus on the comparative evaluation of different marking techniques.

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 P1-01-16: Perspectives on axillary management after primary systemic treatment: An international EUBREAST survey

Background: Consensus on the axillary management in cN+ breast cancer patients whoconvert to ycN0 after primary systemic treatment (PST) is still lacking. A surveywas conducted to investigate the clinical practice in this setting. Materials and Methods: A web-based survey was developed by a multidisciplinary group on behalfof the European Breast Cancer Research Association of Surgical Trialists (EUBREAST),and distributed to breast surgeons and radiation oncologists via breast cancersocieties. Results: We received 345 replies from 43 countries. A majority of responderssuggest FNA/CNB before treatment (81%) while 19 % perform histologic assessmentonly in selected cases. The preferred surgical approach to the axilla in cN1patients who convert to ycN0 is targeted axillary dissection (TAD) 55%,sentinel lymph node biopsy (SLNB) 21%, axillary lymphadenectomy (ALND) (level1-2) 19%, others 5%. When SLNB is preformed, single and dual tracers are usedin 62% and 38% respectively. No minimumnumber of SLNs is required by 36 % of the surgeons, while 8% and 56% suggest toremove at least 2 or 3 SLNs respectively.For targeted lymph node biopsy (TLNB) or TAD, there is a wide heterogeneitywith regards to localization techniques. In case of multiple suspicious nodes, 65%of the responders declared to mark only one node. 47 % of responders routinelyperform an additional preoperative localization of the TLN. Imaging modalitiesto assess the ycN status are: ultrasound (67%), MRI (21%), other(12%). In caseof ambiguous finding before PST (cN+) ALND was suggested by 23 % only after routine histologicconfirmation of lymph node involvement and by 45 % without. 29% of theresponders perform SLNB/TAD/TLNB without additional axillary surgery 3%suggested different approaches. 66 % of the participants recommended ALND in ycN+ patients only after furtherhistologic confirmation, while 23 % do not perform CNB/FNA. 11 % voted forTAD/SLNB/TLNB in this setting. The decision for post-operative regionalirradiation is influenced by initial nodal lymph node status (61 %) and by acombination of pre- and post- PST assessment (39%). 21% of the responders neverirradiate level I in patients with a ypN&gt;1 status after ALND while 37 % suggestselective use of RT and 42 % favoured RT in all patients. Target volumes forelective nodal irradiation are determined mainly based on ESTRO (61%) and RTOG(32%) guidelines.In case of macrometastatic nodal disease (ycN0ypN+) regional nodeirradiation was suggested by 59 % of the participants regardless of the numberof involved nodes. 37 % suggested RT in patients with more than 3 positive nodes,while 4% would never irradiate. After a positive TAD or SLNB radiationoncologists suggest ALND in 63 % and RT in 37%. Similar results were attainedfor ypN1mi and ypN0(i+). 34 % of the breastsurgeons suggested ALND for patientswith ypN1(mi) status after TAD/SLNB, 31 % favored RT, 23% a combination and 12%suggested omission of further reginal treatment. Remodeling fibrotic scarsrarely affect regional treatment planning. Conclusions: The results of this EUBREAST survey highlightthe wide heterogeneity in the approach to the axilla after PST, corroborate theneed for further clinical research and provide the rationale for the AXSANA(EUBREAST 3) study . Supporting Societies:. American Society of Breast Surgeons (ASBrS). Arbeitsgemeinschaft für gynäkologische Onkologie (AGO). Associazione Nazionale Italiana Senologi Chirurghi (ANISC). Collegio Italiano dei Senologi. Deutsche Gesellschaft für Radioonkologie (DEGRO). Deutsche Gesellschaft für Senologie (DGS). Global Breast Hub. Israel Breast Surgeons Society. Israel Radiation Therapy society. Swiss Society of Senology (SSS). Scuola Italiana di Senologia. Società Polispecialistica Italiana Giovani Chirurghi (SPIGC). Swedish Breast Cancer Group. The Oncoplastic Breast Consortium (OPBC)

Citation Format: Maria Luisa Gasparri, Jana De Boniface, Oreste Davide Gentilini, Orit Kaidar-Person, Philip Poortmans, Thorsten Kuehn. Perspectives on axillary management after primary systemic treatment: An international EUBREAST survey [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 P1-01-16.

Breast reconstruction and radiation therapy: An Italian expert Delphi consensus statements and critical review

Breast conserving surgery (BCS) plus radiation therapy (RT) or mastectomy have shown comparable oncological outcomes in early-stage breast cancer and are considered standard of care treatments. Postmastectomy radiation therapy (PMRT) targeted to both the chest wall and regional lymph nodes is recommended in high-risk patients. Oncoplastic breast conserving surgery (OBCS) represents a significant recent improvement in breast surgery. Nevertheless, it represents a challenge for radiation oncologists as it triggers different decision-making strategies related to treatment volume definition and target delineation. Hence, the choice of the best combination and timing when offering RT to breast cancer patients who underwent or are planned to undergo reconstruction procedures should be carefully evaluated and based on individual considerations. We present an Italian expert Delphi Consensus statements and critical review, led by a core group of all the professional profiles involved in the management of breast cancer patients undergoing reconstructive procedures and RT. The report was structured as to consider the main recommendations on breast reconstruction and RT and analyse the current open issues deserving investigation and consensus. We used a three key-phases and a Delphi process. The final expert panel of 40 colleagues selected key topics as identified by the core group of the project. A final consensus on 26 key statements on RT and breast reconstruction after three rounds of the Delphi voting process and harmonisation was reached. An accompanying critical review of available literature was summarized. A clear communication and cooperation between surgeon and radiation oncologist is of paramount relevance both in the setting of breast reconstruction following mastectomy when PMRT is planned and when extensive glandular rearrangements as OBCS is performed. A shared-decision making, relying on outcome-based and patient-centred considerations, is essential, while waiting for higher level-of-evidence data.

The Clinical and Pathological Profile of BRCA1 Gene Methylated Breast Cancer Women: A Meta-Analysis

BACKGROUND

DNA aberrant hypermethylation is the major cause of transcriptional silencing of the breast cancer gene 1 (BRCA1) gene in sporadic breast cancer patients. The aim of the present meta-analysis was to analyze all available studies reporting clinical characteristics of BRCA1 gene hypermethylated breast cancer in women, and to pool the results to provide a unique clinical profile of this cancer population.

METHODS

On September 2020, a systematic literature search was performed. Data were retrieved from PubMed, MEDLINE, and Scopus by searching the terms: "BRCA*" AND "methyl*" AND "breast". All studies evaluating the association between BRCA1 methylation status and breast cancer patients' clinicopathological features were considered for inclusion.

RESULTS

465 studies were retrieved. Thirty (6.4%) studies including 3985 patients met all selection criteria. The pooled analysis data revealed a significant correlation between BRCA1 gene hypermethylation and advanced breast cancer disease stage (OR = 0.75: 95% CI: 0.58-0.97; p = 0.03, fixed effects model), lymph nodes involvement (OR = 1.22: 95% CI: 1.01-1.48; p = 0.04, fixed effects model), and pre-menopausal status (OR = 1.34: 95% CI: 1.08-1.66; p = 0.008, fixed effects model). No association could be found between BRCA1 hypermethylation and tumor histology (OR = 0.78: 95% CI: 0.59-1.03; p = 0.08, fixed effects model), tumor grading (OR = 0.78: 95% CI :0.46-1.32; p = 0.36, fixed effects model), and breast cancer molecular classification (OR = 1.59: 95% CI: 0.68-3.72; p = 0.29, random effects model).

CONCLUSIONS

hypermethylation of the BRCA1 gene significantly correlates with advanced breast cancer disease, lymph nodes involvement, and pre-menopausal cancer onset.

Abstract OT-23-02: Volumetric analysis of the pectoralis major muscle as preoperative tool to select patients undergoing pre-pectoral versus sub-pectoral implant based breast reconstruction after risk reducing mastectomy

Background: Proper patient selection is crucial to maximize aestethic outcome in breast reconstructive surgery. No specific patients selection criteria have been developed to choose between prepectoral versus subpectoral implant-based reconstruction. A quantitative tool able to determine the pectoralis muscle individual characteristics might be helpful to discriminate a priori the patients who will experience better aesthetic outcome and less complications following a pre-pectoral versus a sub-pectoral approach. Preoperative pectoralis muscle assessment may optimize patients’ selection for the breast reconstructive technique. Trial design: This is a multicentric trial in which, patients candidated to risk reducing mastectomy fulfilling inclusion criteria, will undergo a preoperative MRI prior to randomization to pre-pectoral versus sub-pectoral implant placement in immediate breast reconstruction. Volumetric analysis of the pectoralis major muscle (cm2) and measurement of the subcutaneous adipose tissue in the breast region, will be performed to assess anatomic characteristics of the pectoralis muscle using a sagittal T1 fat suppressed sequence. The volume of the pectoralis muscle will be calculated by measuring differences in density with the MRI. In all patients, the pectoralis muscle area on the left and right side will be determined separately and the two values will be averaged. The volumetric assessment will be performed by two expert radiologists. BREAST-Q© questionnaire will be completed by each patient prior to surgery and at the follow up evaluations. Breast reconstruction will be performed immediately after nipple-sparing mastectomy (Arm 1: breast implant placed above the pectoralis major muscle (pre-pectoral); Arm 2: breast implant placed below the pectoralis major muscle (sub-pectoral)). Number of revisional surgeries, explantations, infections, seromas, flap necrosis, will be compared between two groups and correlated with MRI pectoralis muscle volume. Post-operative follow-up evaluations at 6 and 12-months to assess capsular contracture and BREAST-Q changes will be performed. Eligibility criteria:

Inclusion criteria:

•Female patient•Ages 18-60•Patients undergoing risk reducing mastectomy with immediate implant-based reconstruction •Signed informed consent

Exclusion Criteria:

•Prior chest wall irradiation •Patients with a contraindication to immediate breast reconstruction.•Patients with history of smoking, •BMI&gt; 40, •D cup breast size•grade III ptosis

Aims: To identify variables measured at preoperative MRI pectoralis muscle’s volumetric analysis that correlate with aesthetic outcome and complication rate in pre-pectoral versus sub-pectoral implant based reconstruction.

Statistical methods: The assumption of distributional normality will be tested using the Shapiro-Wilk test. Comparisons of two variables will be carried out using the Wilcoxon test for paired groups and the Mann-Whitney test for unpaired groups.

Present accrual and target accrual: The trial has been submitted for IRB approval at the ethical commission of Italian Switzerland. Recruitment has not started yet. With an enrollment ratio of 1:1, fifty patients (25 per arm) need to be recruited to ensure a power of 80% with a two sides alpha error of 0.05.

Contact information: marialuisa.gasparri@eoc.ch

Citation Format: Maria Luisa Gasparri, Thorsten Kuehn, Isabel Rubio, Philip Poortmans, Diana Lueftner, Orit Kaidar-Pearson, Beat Thuerlimann, Yves Harder, Daniel Schmauss, Francesco Meani, Claudia Rauh, Michael David Mueller, Malgorzata Banys-Paluchowski, Andrea Papadia, Valerio Vitale, Stefania Rizzo, Oreste Davide Gentilini. Volumetric analysis of the pectoralis major muscle as preoperative tool to select patients undergoing pre-pectoral versus sub-pectoral implant based breast reconstruction after risk reducing mastectomy [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-23-02.

What we learned in axillary management of breast cancer patients at the American society of clinical oncology (ASCO) 2020 virtual meeting? The EUBREAST point of view

In 2020, the American Society of Clinical Oncology (ASCO) annual meeting was held as a virtual conference. Overall, 461 abstracts focused on breast cancer management. As European Breast Cancer Association of Surgical Trialists (EUBREAST) we summarize and comment the results of these abstracts dealing with axillary management in breast cancer patients and offer an interpretation on how these findings may be incorporated into clinical practice and further research.

Changes in breast cancer management during the Corona Virus Disease 19 pandemic: An international survey of the European Breast Cancer Research Association of Surgical Trialists (EUBREAST)

Background

Corona Virus Disease 19 (COVID-19) had a worldwide negative impact on healthcare systems, which were not used to coping with such pandemic. Adaptation strategies prioritizing COVID-19 patients included triage of patients and reduction or re-allocation of other services. The aim of our survey was to provide a real time international snapshot of modifications of breast cancer management during the COVID-19 pandemic.

Methods

A survey was developed by a multidisciplinary group on behalf of European Breast Cancer Research Association of Surgical Trialists and distributed via breast cancer societies. One reply per breast unit was requested.

Results

In ten days, 377 breast centres from 41 countries completed the questionnaire. RT-PCR testing for SARS-CoV-2 prior to treatment was reported by 44.8% of the institutions. The estimated time interval between diagnosis and treatment initiation increased for about 20% of institutions. Indications for primary systemic therapy were modified in 56% (211/377), with upfront surgery increasing from 39.8% to 50.7% (p < 0.002) and from 33.7% to 42.2% (p < 0.016) in T1cN0 triple-negative and ER-negative/HER2-positive cases, respectively. Sixty-seven percent considered that chemotherapy increases risks for developing COVID-19 complications. Fifty-one percent of the responders reported modifications in chemotherapy protocols. Gene-expression profile used to evaluate the need for adjuvant chemotherapy increased in 18.8%. In luminal-A tumours, a large majority (68%) recommended endocrine treatment to postpone surgery. Postoperative radiation therapy was postponed in 20% of the cases.

Conclusions

Breast cancer management was considerably modified during the COVID-19 pandemic. Our data provide a base to investigate whether these changes impact oncologic outcomes.

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Management of breast cancer patients was modified during the pandemic.

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Waiting time increased during the pandemic in 20% of the institutions.

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A workload reduction of ≥50% was reported in 1/3 and relocation of the centres in 13%.

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It is unknown whether these changes will affect outcome of breast cancer patients.

Personalized Risk-Benefit Ratio Adaptation of Breast Cancer Care at the Epicenter of COVID-19 Outbreak

Northern Italy has been one of the European regions reporting the highest number of COVID-19 cases and deaths. The pandemic spread has challenged the National Health System, requiring reallocation of most of the available health care resources to treat COVID-19-positive patients, generating a competition with other health care needs, including cancer. Patients with cancer are at higher risk of developing critical illness after COVID-19 infection. Thus, mitigation strategies should be adopted to reduce the likelihood of infection in all patients with cancer. At the same time, suboptimal care and treatments may result in worse cancer-related outcome. In this article, we attempt to estimate the individual risk-benefit balance to define personalized strategies for optimal breast cancer management, avoiding as much as possible a general untailored approach. We discuss and report the strategies our Breast Unit adopted from the beginning of the COVID-19 outbreak to ensure the continuum of the best possible cancer care for our patients while mitigating the risk of infection, despite limited health care resources. IMPLICATIONS FOR PRACTICE: Managing patients with breast cancer during the COVID-19 outbreak is challenging. The present work highlights the need to estimate the individual patient risk of infection, which depends on both epidemiological considerations and individual clinical characteristics. The management of patients with breast cancer should be adapted and personalized according to the balance between COVID-19-related risk and the expected benefit of treatments. This work also provides useful suggestions on the modality of patient triage, the conduct of clinical trials, the management of an oncologic team, and the approach to patients' and health workers' psychological distress.

Rare sites of breast cancer metastasis: a review

Breast cancer (BC) metastasis accounts for the majority of deaths from BC. The rate of metastasis to uncommon sites is on the rise due to the more effective therapy prolonging survival and to the early detection on imaging. The evaluation of patient-reported symptoms is essential in detecting a recurrence as early as possible, which may impact survival. Hence, the knowledge of even the rare sites of BC metastasis is of paramount importance for the clinical interpretation of new symptoms in BC survivors. The term “unusual metastasis” defines a systemic failure with a frequency of ≤1% at each site and according to this unusual metastasis involve the central nervous system, secretory/endocrine organs and glands, internal organs and structures, and gynecological organs. The literature search was performed using the electronic database PubMed up to December 2018, with the following key words: {[rare(Title/Abstract)] OR [unusual(Title/Abstract)] OR [unconventional(Title/Abstract)]} AND {[metastases(Title/Abstract)] OR [metastasis(Title/Abstract)]} AND {[breast(Title/Abstract)]} AND {[cancer(Title/Abstract)] OR [tumor(Title/Abstract)] OR [tumour(Title/Abstract)] OR [neoplasm(Title/Abstract)]}. The search was limited to papers in English language. Of the 3,086 papers found, 757 were excluded as reporting animal models, 378 were not in English language, 1 was a duplicate of the same research, 1,414 did not report on BC metastases, 108 were previous review reviews on BC or tumour to tumour metastases; 428 papers were included in this review. Despite the improvements in BC management, most deaths from cancer result from metastases that are resistant to conventional therapies. In general, it is uncommon to find isolated rare metastases, the vast majority of these develops together with metastases in other sites, thus highlighting a worsening systemic disease. However, the early detection of even rare metastases represents the only chance to control the disease and prolong survival while waiting for the development of more effective systemic therapies.

Management of breast cancer during pregnancy: Results of a large registry from a single institution

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Background: Given the rising trend of delaying pregnancy to later in life, more women are diagnosed with breast cancer during pregnancy. Management is still controversial and relies on expert guidelines. Thus the experience of single centres with high patients’ volume remains of interest. Methods: All breast cancer patients (pts) diagnosed at the European Institute of Oncology (IEO) in Milan were included in a specific registry since 1995. Results: Out of 8340 patients < 47 y/o registered up to Dec 2012, 167 were diagnosed during pregnancy (2%). Median age was 36 years (24-47y). Median gestational age was 18 weeks (1-38 w). 73 % pts had a pT1-2 tumor, with positive nodes in 48%. 9,6% had luminal A, 38% luminal B, 26% basal like and 16% HER2+ tumors, according to St Gallen criteria. 29/167 pts (17%) opted for an induced abortion. Of the remaining 97 pts, 81 (84%) underwent definitive surgery during pregnancy; 58 (72%) and 23 pts (28%) had quadrantectomy and mastectomy, respectively. Immediate breast reconstruction was performed in 13 cases. Sentinel node procedure (SLN) was performed in 42 pts (52%), with positive axilla in 10 pts. 41 pts (51%) received chemotherapy during pregnancy. Regimens included weekly epirubicin (24 pts), EC/AC (12 pts), FAC/FEC (3 pts), q21 epirubicin (2 pts). No G3-G4 toxicities were reported. No pregnancy complications were observed, with the exception of 1 case of premature delivery at 28 weeks. Median gestational age at delivery was 36 weeks (29-40 w). No major malformations were observed. Gestational age at birth and birth-weight were similar in babies who received chemotherapy in-utero (36 w and 2555g) and in babies who did not receive gestational chemotherapy (37w and 2600g). At a median follow-up of 42 months (range: 1-178 m), all children had normal neurological and physical development with no late adverse effects observed. Conclusions: Managing breast cancer during pregnancy should follow standard practice as in non-pregnant pts. Surgeries like SLN and breast reconstruction were performed with no serious complications. Our results further emphasize the safety of anthracycline-based gestational chemotherapy without major effects on pregnancy course or fetal health.

Metformin effects on cancer adjacent breast preneoplasia in a randomized pre-surgical trial

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Background: Metformin has been associated with a significant reduction in cancer incidence and mortality in diabetic patients, including positive results in breast cancer. In a window-of-opportunity trial in 200 non-diabetic women with breast cancer, we showed a heterogeneous effect of metformin on breast cancer proliferation (Ki-67) depending on insulin resistance, with a trend to a decreased proliferation in women with insulin resistance (HOMA>2.8) and an opposite trend in women with normal insulin sensitivity (Bonanni et al. JCO 2012). Here we determined whether metformin has antiproliferative effects on adjacent lobular or ductal intraepithelial neoplasia (LIN or DIN) and on distant ductal hyperplasia and whether these effects are different according to specific host and tumor characteristics. Methods: Baseline core biopsies of tumor tissue and blood samples were obtained at study entry and before surgery for pre/post-treatment comparisons. Patients were randomly assigned to metformin, 850 mg or placebo once daily on day 1-3 followed by two 850 mg tablets from day 4 to 28. At surgery, three to five specimens of adjacent (≤1 cm from the tumor) and distant (>1 cm from the tumor) grossly normal tissue were obtained to assess systematically the prevalence, grade and proliferation of LIN or DIN and ductal hyperplasia. Results: Overall, the prevalence of LIN, DIN and ductal hyperplasia was 4.5% (9/200), 66.5% (133/200) and 35% (69/200), respectively. Ki-67 was positively associated with DIN grade (p-trend<0.001). The median (and IQ range) Ki-67 LI distribution of LIN+DIN was 12% (8-20) and 10% (6-22) on metformin and placebo, respectively (p=0.6). Compared with placebo, metformin exhibited different effects on Ki-67 according to DIN grade (delta=+4.4% in DIN1 vs -27.9% in DIN3, p-interaction=0.09), cancer HER2 status (median 12% vs. 10% in HER2-ve; 28% vs. 35% in HER2+ve, p=0.03), abdominal circumference (p=0.08), and BMI (p=0.17). Conclusions: Metformin had no overall significant effect on breast preneoplasia proliferation but exhibited heterogeneous effects depending upon host and tumor characteristics. The significant reduction of HER2+ve, DIN3 proliferation under metformin warrants further studies. Clinical trial information: 16493703.

Abstract PD03-01: EFFECT OF METFORMIN ON APOPTOSIS IN A PRESURGICAL TRIAL IN NON-DIABETIC PATIENTS WITH BREAST CANCER

BACKGROUND: metformin has been associated with antitumor activity in epidemiological and clinical studies. This effect has been related to different mechanisms of actions, including a reduction of the proliferative activity and an increase of apoptosis. We have recently shown that a 4 week pre-surgical treatment with metformin did not affect Ki-67 LI overall but reduced tumor proliferation Ki67 LI in breast cancer (BC) patients with insulin resistance (IR) (HOMA, fasting blood glucose (mmol/L)*insulin (mU/L)/22.5&gt;2.8) or BMI&gt;27 (Bonanni et al. JCO epub May 7, 2012). The objective of the current analysis was to determine whether metformin induced a modulation of apoptosis (TUNEL) overall and by HOMA index.

TRIAL DESIGN: After tumor biopsy we randomly allocated 200 non-diabetic women with operable breast cancer to either metformin (850 mg/bid) or placebo for 4 weeks prior to surgery. The primary outcome measure was the difference between arms in Ki-67 after 4 weeks of treatment. Here we analyzed the apoptotic cell nuclei in 88 consecutive core biopsies and their paired surgical samples from the initial 100 randomized subjects.

RESULTS: Median TUNEL levels at surgery (Metformin = 10%, IQR, 4–20, Placebo = 8%, IQR, 3–15) were significantly higher as compared with baseline (Metformin = 4%, IQR, 2–7, Placebo = 3%, IQR, 2–6, p &lt; 0.0001), but no difference between arms was noted (p = 0.2, adjusted for age, BMI, TUNEL and Ki67 at baseline). Interestingly, Ki67 and TUNEL levels were highly and positively correlated both at baseline and at surgery (Spearman r=0.51, p &lt; 0.0001). Furthermore, we found a trend to a different metformin effect by the HOMA index (p = 0.1). In the 59 women with HOMA &lt;2.8 there was a higher level of TUNEL at surgery on metformin versus placebo (p = 0.05), while an opposite trend was found in the 28 women with HOMA&gt;2.8 (p = 0.6).

CONCLUSIONS: The levels of TUNEL are significantly higher in the surgical specimens compared with baseline biopsy and are directly correlated with those of Ki-67 (TUNEL is high when Ki-67 is high). We found no significant modulation of TUNEL by metformin but a trend to a different effect according to the IR state, with a similar pattern to Ki-67: decrease by metformin in IR women and increase in non-IR women. Our findings confirm the notion that metformin has dual effects on breast cancer according to IR state. As expected, cancer apoptosis and proliferation are directly related. Our results strengthen the importance of placebo control arms in biomarker trials.

ACKNOWLEDGEMENTS: 2 Grants by AIRC and Italian Ministry of Health.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr PD03-01.

Preoperative oral supplement with immunonutrients in cancer patients

BACKGROUND

Early postoperative enteral nutrition with immune-enhancing supplements has helped to restore immune function and reduce infectious complications in patients with cancer undergoing major gastrointestinal operations. The aim of this study was to evaluate the effectiveness of similar supplements (containing arginine and arginine plus omega-3 fatty acids) given preoperatively for 1 week before cancer surgery.

METHODS

In this randomized, double-blinded study, patients scheduled to undergo elective resection of upper gastrointestinal tumors were given one of three different oral liquid supplemental diets (control, arginine, arginine plus omega-3 fatty acids) to be taken each day for 7 days before surgery. Blood samples were obtained upon enrollment, on the morning of surgery, and on postoperative day 1 for analysis of immunologic function.

RESULTS

Mean serum ornithine (a metabolite of arginine) levels were significantly higher compared with controls, but no significant increase in mean serum arginine levels was noted on the morning of surgery for those patients who received arginine as part of the supplement. In conjunction with these findings, there were no differences among groups in mean lymphocyte mitogenesis, mean peripheral blood mononuclear cell production of cytokines, or clinical outcomes.

CONCLUSIONS

Use of oral liquid supplements in this fashion did not improve lymphocyte proliferation or monocyte functions in patients with cancer undergoing major surgery.