Breast Conservation Rate Research Articles

Increasing opportunities for breast-conserving therapy in multiple ipsilateral breast cancer: Dutch nationwide study.

An increasing number of breast cancer patients undergo breast-conserving surgery (BCS), but multiple ipsilateral breast cancer (MIBC) is still considered a relative contraindication for breast conservation. This study provides an update on trends in the surgical management for MIBC over a 10-year period. Nationwide data from the Netherlands Cancer Registration of all patients diagnosed with breast cancer between 2011 and 2021 were analysed. The primary outcomes of this study were the incidence of MIBC and the trend in breast surgery type among patients between 2011 and 2021. Secondary outcomes were the positive resection margin rates in patients treated with BCS, the proportion of patients requiring re-excision and overall survival. In total, 114 433 patients (83%) with unifocal breast cancer and 23 932 patients (17%) with MIBC were identified. The incidence of MIBC was stable (17%) over the years. Overall BCS rates, both primary and after neoadjuvant chemotherapy, increased in MIBC from 29% in 2011 to 41% in 2021. Re-excision was performed in 1348 patients (n = 8455, 16%). The 5-year OS estimate for patients with MIBC treated with BCS was 93%. The pathological complete response (pCR) in MIBC patients treated with neoadjuvant chemotherapy followed by mastectomy was 23%. The breast conservation rate in MIBC has increased over the last decade. In addition, 23% of MIBC patients treated with neoadjuvant chemotherapy followed by mastectomy achieved a pCR. This suggests increasing opportunities for even more BCS in MIBC.

18F-FDG PET/CT for early prediction of pathological complete response in breast cancer neoadjuvant therapy: a retrospective analysis.

Neoadjuvant treatment has been developed as a systematic approach for patients with early breast cancer and has resulted in improved breast-conserving rate and survival. However, identifying treatment-sensitive patients at the early phase of therapy remains a problem, hampering disease management and raising the possibility of disease progression during treatment. In this retrospective analysis, we collected 2-deoxy-2-[F-18] fluoro-d-glucose (18F-FDG) positron emission tomography (PET)/computed tomography (CT) images of primary tumor sites and axillary areas and reciprocal clinical pathological data from 121 patients who underwent neoadjuvant treatment and surgery in our center. The univariate and multivariate logistic regression analyses were performed to investigate features associated with pathological complete response (pCR). An 18F-FDG PET/CT-based prediction model was trained, and the performance was evaluated by receiver operating characteristic curves (ROC). The maximum standard uptake values (SUVmax) of 18F-FDG PET/CT were a powerful indicator of tumor status. The SUVmax values of axillary areas were closely related to metastatic lymph node counts (R = 0.62). Moreover, the early SUVmax reduction rates (between baseline and second cycle of neoadjuvant treatment) were statistically different between pCR and non-pCR patients. The early SUVmax reduction rates-based model showed great ability to predict pCR (AUC = 0.89), with all molecular subtypes (HR+HER2-, HR+HER2+, HR-HER2+, and HR-HER2-) considered. Our research proved that the SUVmax reduction rate of 18F-FDG PET/CT contributed to the early prediction of pCR, providing rationales for utilizing PET/CT in NAT in the future.

NRG-BR007: A phase III trial evaluating de-escalation of breast radiation (DEBRA) following breast-conserving surgery of stage 1, HR+, HER2-, RS ≤18 breast cancer.

TPS622 Background: Approximately 50% of newly diagnosed invasive breast cancers are stage 1, with the majority being ER/PR-positive, HER2-negative. Genomic assays such as the Oncotype DX have identified patients (pts) with reduced risk of distant metastasis and without benefit from chemotherapy added to endocrine therapy, freeing them from excess toxicity. Genomic assays are also recognized as prognostic for in-breast recurrence (IBR) after BCS and could similarly allow de-escalation of adjuvant radiotherapy (RT). Reducing overtreatment is of interest to pts, providers, and payers. Methods: We hypothesize that breast-conserving surgery (BCS) alone is non-inferior to BCS plus RT for IBR and breast preservation in women intending endocrine therapy (ET) for stage 1 invasive breast cancer (ER and/or PR-positive, HER2-negative with an Oncotype DX Recurrence Score [RS] of ≤18). Stratification is by age (<60; ≥60), tumor size (≤1 cm; >1-2cm), and RS (≤11, >11-18/MammaPrint Low). Pts are randomized post-BCS to Arm 1 with breast RT using standard methods (moderate or ultra hypo- or conventional-fractionated whole breast RT with/without boost, or APBI) with ≥5 yrs of ET (tamoxifen or AI) or Arm 2 with ≥5 yrs of ET (tamoxifen or AI) alone. The specific regimen of ET in both arms is at the treating physician’s discretion. Eligible pts are stage 1: pT1 (≤2 cm), pN0, age ≥50 to <70 yrs, s/p BCS with negative margins (no ink on tumor), s/p axillary nodal staging (SNB or ALND), ER and/or PR-positive (ASCO/CAP), HER2-negative (ASCO/CAP), and Oncotype DX RS ≤18 (diagnostic core biopsy or resected specimen); (a “low risk” MammaPrint is permissible if completed as part of usual care prior to screening). Primary endpoint is IBR (invasive breast cancer or DCIS). Secondary endpoints are breast conservation rate, invasive in-breast recurrence, relapse-free interval, distant disease-free survival, overall survival, patient-reported breast pain, patient-reported worry about recurrence, and adherence to ET. We assume a clinically acceptable difference in IBR of 4% at 10 yrs to judge omission of RT as non-inferior (10-yr event-free survival for RT group is 95.6% v 91.6% for the omission-of-RT group). BR007 is powered to detect non-inferiority with 80% power and a one-sided α=0.025, assuming that there would be a ramp-up in accrual in the first two years (leveling off in yrs 3-5); 1,670 pts (835 per arm) are required for randomization. Conservative loss to follow-up is 1%/yr. Some T1a pts screened may have Oncotype DX scores >18, making them ineligible for the study. In the accrual process, 1,714 pts will be required to register to ensure that our final randomized cohort is 1,670 pts. Current accrual (02-05-2024) is 805 screened and 716 randomly assigned. Clinical trial information: NCT04852887 .

Abstract PO2-23-05: Practice patterns and outcomes in the ongoing neoadjuvant ATNEC trial: node marking, response to NACT and breast conservation rates

Abstract Background In ATNEC trial, cT1-3N1M0 patients receive NACT followed by SNB/TAD. If the sentinel nodes(SNs) have converted to benign(ypN0), patients are randomly assigned to Axillary Treatment vs no Axillary Treatment. The study promotes standardized node marking procedures and includes a radiotherapy quality assurance program. Objectives – This study prospectively evaluates practice patterns, NACT response, adoption of node marking, rates of marked node identification, and breast conservation rates in the ongoing ATNEC trial across 70 centers in the UK. The trial aims to recruit 1900 patients. Materials and Methods Data from 196 randomized patients (median age: 54 [range: 28-79] years; median BMI: 26.5 [range: 17.6-51.1]) from December 2021 to June 28, 2023, across 70 UK centers were analyzed. These patients presented with cT1-3N1M0 breast cancer, received NACT, and exhibited no residual nodal disease (ypN0) on SNB/TAD. Results Among the randomised patients 54%(106) were post-menopausal, 71%(140) underwent breast conserving surgery(BCS) and 29%(56) mastectomy. At presentation, 12% (23) had T3, 63% (124) had T2, and 23% (46) had T1 tumors. Grade 3 tumors accounted for 70% (138) of cases. Among the patients, 60% (117) were HER2 positive, 31% (61) were triple negative, and 9% (18) were HER2 negative (ER or PgR positive). Anthracycline and taxane-based NACT were administered to 57% (106), while 38% (71) received a platinum-containing regimen. During SNB/TAD, a median of 4 nodes (interquartile range, 3-5) were removed. Among 184 patients with node marking data, 74% (136) had the involved node marked. The marked node was successfully removed in 94% (128) of these patients. Clip/coil only, Magseed and black dye were the commonest techniques used for node marking. The marked node was the sentinel node in 83% (106) of cases. Among 185 randomized patients with post-NACT response data, 68% (125) achieved a complete pathological response (pCR) in the breast, while 8% (15) had DCIS only and 22% (41) had invasive cancer. Among 105 patients with complete breast tumor response on imaging, 15% (16) had residual DCIS or invasive cancer. In the subset of patients with partial response or stable breast tumors on imaging (69 patients), 46% (32) had no residual tumor on histology (ypT0). Furthermore, 14% (26) exhibited partial or stable disease in the axilla on imaging but achieved complete pathological response on histology. Conclusions HER2-positive and triple-negative breast cancer cases predominate among patients undergoing NACT in the UK. Although 68% achieved a complete pCR (ypT0) in the breast, rates of BCS remain low. Notably, around 75% of randomized patients underwent node marking, with an intra-operative identification rate of 94%, demonstrating the successful implementation of node marking in the UK through the ATNEC trial. Citation Format: Amit Goyal, Andrea Marshall, Sophie Nicholls, Natalie Hammonds, Beatrix Elsberger, Duncan Wheatley, Janice Rose, Helen-Teresa Edwards, Abeer Shaaban, Roeum Butt, Gareth Jackson, Tara Homer, Luke Vale, Samreen Ahmed, Shama Puri, Sophie Gasson, Julie Bruce, Helen Higgins, Janet Dunn. Practice patterns and outcomes in the ongoing neoadjuvant ATNEC trial: node marking, response to NACT and breast conservation rates [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO2-23-05.

Abstract PO5-18-09: Anthracycline-free neoadjuvant therapy with nab-paclitaxel and carboplatin in non-luminal breast cancer: a single-arm phase II trial

Abstract Background Anthracycline and taxane-based chemotherapy are the corner stone of neoadjuvant therapy in early breast cancer. Anthracycline-free regimens have been addressed widely because of cardiac toxicity especially in HER2-positive breast cancer when combining trastuzumab and pertuzumab. Aim of this trial was to assess the efficacy and safety of nab-paclitaxel combined with carboplatin in the neoadjuvant therapy of non-luminal breast cancer. Methods The Neopath trial was a prospective, single-arm phase II trial conducted in Comprehensive Breast Health Center, Ruijin Hospital between April 2019 and October 2021. Patients who had cT2-4NanyM0 or cTanyN1-3M0 triple negative breast cancer (TNBC) or HER2-positive breast cancer were enrolled. Patients were treated with neoadjuvant nab-paclitaxel (100 mg/m2) and carboplatin (area under the curve 2) on days 1, 8, and 15, for four 4-week cycles. Concurrent trastuzumab at 2 mg/kg (loading dose 4 mg/kg) and pertuzumab 420 mg (loading dose 840 mg) were given in patients with HER2-positive tumors. Surgery was performed after 4-6 cycles of neoadjuvant therapy. Trastuzumab and pertuzumab after surgery was continued every 3 weeks for a total duration of 1 year. The primary endpoint was pathological complete response (pCR) rate, defined as no invasive tumor in breast and axillary lymph nodes (ypT0/Tis N0) after neoadjuvant therapy. Secondary endpoints were pCR rate in predefined subgroups, pCR (ypT0 N0), objective response rate (ORR); event-free survival (EFS), breast conservation rate and toxicity. Results A total of 106 patients were enrolled in the study and 99 of them proceeded to surgery. The pCR (ypT0/is N0) rate was 41.41% in total, 33.78% in TNBC and 64.00% in HER2-positive breast cancer. Proportion of patients achieving pCR (ypT0 N0) was 38.38% in total, 31.08% in TNBC and 60.00% in HER2-positive tumors. In the ITT population, 93 patients were event-free at a median follow-up of 24 months, while 5 in TNBC group and 1 in HER2-positive group had relapse or distant metastasis. EFS in patients achieving pCR was higher than patients without pCR (HR=7.328, 95%CI=1.453-36.96, p=0.0158). ORR was 72.49% in total, 67.12% in TNBC and 88.00% in HER2-positive breast cancer. Total breast conservation rate was 10.1% and 12.2% in TNBC, 4.0% in HER2-positive subgroup. The most frequent grade 3 or higher adverse events were neutropenia (57%), vomiting (11%) and thrombocytopenia (8%). Conclusion Neoadjuvant anthracycline-free regimen of nab-paclitaxel combined with carboplatin in non-luminal breast cancer was an effective and well-tolerated regimen. Citation Format: Deyue Liu, Li Zhu, Jiayi Wu, Wei Wang, Shuning Ding. Anthracycline-free neoadjuvant therapy with nab-paclitaxel and carboplatin in non-luminal breast cancer: a single-arm phase II trial [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO5-18-09.

Abstract PO1-19-02: A phase III trial evaluating De-escalation of Breast Radiation (DEBRA) following breast-conserving surgery (BCS) of stage 1, HR+, HER2-, RS ≤18 breast cancer: NRG-BR007

Abstract Background: Approximately 50% of newly diagnosed invasive breast cancers are stage 1, with the majority being ER/PR-positive, HER2-negative. Genomic assays such as the Oncotype DX® have identified patients (pts) with reduced risk of distant metastasis and without benefit from chemotherapy added to endocrine therapy, freeing them from excess toxicity. Genomic assays are also recognized as prognostic for in-breast recurrence (IBR) after BCS and could similarly allow de-escalation of adjuvant radiotherapy (RT). Reducing overtreatment is of interest to pts, providers, and payers. Methods: We hypothesize that BCS alone is non-inferior to BCS plus RT for in-breast recurrence and breast preservation in women intending endocrine therapy (ET) for stage 1 invasive breast cancer (ER &/or PR positive, HER2-negative with an Oncotype DX Recurrence Score [RS] of ≤18). Stratification is by age (< 60; ≥60), tumor size (≤1 cm; >1-2cm), and RS (< 11, 11-18). Pts are randomized post-BCS to Arm 1 with breast RT using standard methods (hypo- or conventional-fractionated whole breast RT with/without boost, or APBI) with ≥5 yrs of ET (tamoxifen or AI) or Arm 2 with ≥5 yrs of ET (tamoxifen or AI) alone. The specific regimen of ET in both arms is at the treating physician’s discretion. Eligible pts are stage 1: pT1 (≤2 cm), pN0, age ≥50 to < 70 yrs, s/p BCS with negative margins (no ink on tumor), s/p axillary nodal staging (SNB or ALND), ER &/or PR positive (ASCO/CAP), HER2-negative (ASCO/CAP), and Oncotype DX RS of ≤18 (diagnostic core biopsy or resected specimen). Primary endpoint is in-breast recurrence (invasive breast cancer or DCIS). Secondary endpoints are breast conservation rate, invasive in-breast recurrence, relapse-free interval, distant disease-free survival, overall survival, patient-reported breast pain, patient-reported worry about recurrence, and adherence to ET. We assume a clinically acceptable difference in IBR of 4% at 10 yrs to judge omission of RT as non-inferior (10-yr event-free survival for RT group is 95.6% vs 91.6% for the omission of RT group). BR007 is powered to detect non-inferiority with 80% power and a one-sided α=0.025, assuming that there would be a ramp-up in accrual in the first two years (leveling off in Yrs 3-5); 1,670 pts (835 per arm) are required for randomization. Conservative loss to follow-up is 1% per yr. Some of the T1a pts screened may have Oncotype DX scores >18, making them ineligible for the study. In the accrual process, 1,714 pts will be required to register to ensure that our final randomized cohort is 1,670 pts. Current accrual (07-07-2023) is 555 screened and 488 randomized (~96% of predicted accrual). Support: U10CA180868, -180822, UG1CA189867, UG1CA189867; Susan G. Komen Foundation (JRW). NCT: 04852887. Citation Format: Julia White, Reena Cecchini, Eleanor Harris, Eleftherios Mamounas, Daniel Stover, Patricia Ganz, Reshma Jagsi, Stewart Anderson, Carmen Bergom, Valérie Théberge, Mahmoud El-Tamer, Richard Zellars, Dean Shumway, Guang-Pei Chen, Thomas Julian, Norman Wolmark. A phase III trial evaluating De-escalation of Breast Radiation (DEBRA) following breast-conserving surgery (BCS) of stage 1, HR+, HER2-, RS ≤18 breast cancer: NRG-BR007 [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO1-19-02.

Abstract PO4-18-04: An exploratory study of Trastuzumab Deruxtecan neoadjuvant therapy in HER2-positive or HER2-low early or locally advanced breast cancer after a poor response to neoadjuvant chemotherapy

Abstract Background The current standard of care for neoadjuvant treatment of HER2-positive early-stage breast cancer consists of dual HER2-blockade with trastuzumab (H) plus pertuzumab (P) and polychemotherapy with a pathological complete response (pCR) rate of 31%~50%. Trastuzumab deruxtecan (T-DXd) is an antibody-drug conjugate composed of an anti-HER2 antibody, a cleavable tetrapeptide-based linker, and a cytotoxic topoisomerase I inhibitor. T-DXd significantly prolonged progression-free and overall survival vs trastuzumab emtansine in HER2-positive unresectable and/or metastatic breast cancer (mBC) previously treated with H and taxane in DESTINY-Breast03 study. HER2-low breast cancer is currently treated as HER2-negative (HER2-low and HER2-zero) breast cancer, with patients stratified according to hormone-receptor (HR) status. In DESTINY-Breast04 study, T-DXd resulted in significantly longer progression-free and overall survival than the physician’s choice of chemotherapy in HER2-low mBC. Given the efficacy of T-DXd monotherapy in HER2-positive or HER2-low mBC, we conduct an exploratory study to evaluate the efficacy and safety of T-DXd in HER2-positive or HER2-low early or locally advanced breast cancer after a poor response to neoadjuvant chemotherapy, and to identify sensitive biomarkers for T-DXd neoadjuvant therapy. Methods Eligible patients were women aged 18 years to 75 years with clinical stage cT2–cT4/cN0–cN3/cM0 (stage II–III) invasive breast cancer (>2 cm in size) confirmed as HER2-positive (immunohistochemistry [IHC] 3+) or HER2-low (IHC2+ or IHC1+/situ hybridization-negative). Patients are required to have an Eastern Cooperative Oncology Group performance status of 0 or 1, and baseline left ventricular ejection fraction of at least 55% (as measured by echocardiogram). Patients are also required to have adequate organ function and bone marrow function. Patients with HER2-positive breast cancer should receive taxane (paclitaxel or nab-paclitaxel) or docetaxel, carboplatin, and H plus P for 2 cycles. Patients with HER2-low and HR-positive breast cancer should receive taxane (paclitaxel or nab-paclitaxel) or docetaxel, and cisplatin or carboplatin for 2 cycles. Patients with HER2-low and HR-negative breast cancer should receive taxane (paclitaxel or nab-paclitaxel) or docetaxel, and anthracycline (epirubicin, pirarubicin or liposomal doxorubicin) for 2 cycles. For patients who have responses of stable disease assessed by magnetic resonance imaging will receive T-DXd neoadjuvant therapy. T-DXd will be administered intravenously every 3 weeks at a dose of 5.4 mg per kilogram of body weight for 4 cycles. Peripheral blood and biopsy tissue will be collected before neoadjuvant chemotherapy and T-DXd neoadjuvant therapy, and peripheral blood and surgical tissue will be collected after the surgery. Lipid metabolites in peripheral blood and mass spectrometry-based protein quantification in tissue will be detected to find sensitive biomarkers for T-DXd neoadjuvant therapy. The primary endpoint is pCR rate (ypT0/Tis ypN0) and identify sensitive biomarkers for T-DXd neoadjuvant therapy. Secondary endpoints include objective response rate, breast-conserving rate and invasive disease-free survival. Citation Format: Jin Zhang, Zhendong Shi, Jingjing Liu. An exploratory study of Trastuzumab Deruxtecan neoadjuvant therapy in HER2-positive or HER2-low early or locally advanced breast cancer after a poor response to neoadjuvant chemotherapy [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO4-18-04.

Abstract PO1-02-04: The efficacy of endocrine therapy during the waiting period for surgery for hormone receptor-positive breast cancer

Abstract Background: Although neoadjuvant endocrine therapy has been used to improve breast conservation rate, its prognostic relevance is unknown. The search for a valid prognostic factor equivalent to pCR in neoadjuvant chemotherapy is a current challenge in neoadjuvant endocrine therapy. In this study, we investigated the efficacy of short term neoadjuvant endocrine therapy utilizing the waiting period for surgery and the prognostic factor including Preoperative Endocrine Prognostic Index (PEPI) score. Methods: A total of 480 patients with StageⅠ-Ⅲ hormone receptor-positive, HER2-negative breast cancer was treated with endocrine therapy during the waiting period for surgery between October 2012 and December 2021. Premenopausal and postmenopausal patients received tamoxifen (TAM) and non-steroidal aromatase inhibitor (AI), respectively. The primary endpoint was change in tumor size by ultrasound and Ki67 expression before and after short term endocrine therapy. The secondary endpoint was prognosis of patients divided by PEPI score which was calculated using tumor size, lymph node metastasis, Ki67 expression, and ER Allred score. This study was approved by the institutional review board of Teikyo University. Results: Median age and tumor size of the entire 480 patients was 55 years (range, 31 - 89), 1.65 cm (range, 0.4 – 7.5), respectively. The median duration of endocrine therapy was 39 days (range, 1-90). 19 (0.3 %) pts were clinically node-positive. Of the entire 480 patients, 211 and 269 patients had TAM and AI, respectively. After short term endocrine therapy, the tumor size was significantly reduced from 1.83cm to 1.62cm in AI group (p=0.02), although TAM did not decrease the tumor size (p=0.89). The Ki67 expression was significantly decreased from 16.4% to 11.3% in TAM group (p=0.002), and from 15.9% to 6.98% in AI group (p < 0.001). There were significant differences in the distribution of PEPI scores between TAM and AI group (p < 0.05) (Table). At the median follow-up of 1012 days, patients with PEPI score ≥ 4 showed worse disease-free survival compared with patients with PEPI score < 4 in TAM group (Figure1). Overall survival is not available because there were no deaths in TAM group. At the median observation period of 833 days, patients with PEPI score ≥ 4 showed worse disease-free survival compared with patients with PEPI score < 4 in AI group (Figure2). In terms of mortality, patients with PEPI score ≥ 4 had worse overall survival than patients with PEPI score 0 and 1-3 (p=0.07). Conclusions: These results suggested that neoadjuvant endocrine therapy during the waiting period for surgery might be effective in reducing Ki67 expression level and PEPI score might be useful in predicting the prognosis of hormone receptor positive breast cancer patients. Table. Distribution of PEPI score Figure 1. Disease-free survival in patients treated with tamoxifen Figure 2. Disease-free survival in patients treated with non-steroidal aromatase inhibitor Citation Format: Yuka Maeda, Saki Naruse, Yuka Isono, Ayana Sato, Akiko Matsumoto, Tatsuhiko Ikeda, Hiromitsu Jinno. The efficacy of endocrine therapy during the waiting period for surgery for hormone receptor-positive breast cancer [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO1-02-04.

The importance of the multidisciplinary team in the decision-making process of patients undergoing neoadjuvant chemotherapy for breast cancer

Background and objectivesRecent literature suggests that rates of breast conservation surgery (BCS) are lower than expected in patients submitted to neoadjuvant chemotherapy (NAC) for breast cancer. The aim of this study was to underscore the role of the multidisciplinary team (MDT) in the decision-making process of patients who underwent breast surgery after NAC.MethodsWe conducted a retrospective study on patients with breast cancer treated according to an algorithm developed at the Breast Unit of Northern Sardinia between January 2019 and May 2023. Data collected included demographics, tumor characteristics, upfront treatment (surgery or NAC), type of primary surgery (BCS or mastectomy [Ma]) and patients’ adherence to the treatment proposed by the MDT.ResultsOverall, 1061 women were treated during the study period, of whom 164 received NAC (Group A) and 897 upfront surgery (Group B). In group A, conversion from BCS ineligibility to BCS eligibility was observed in 47 patients (40.1%). Final surgery in patients who became BCS-eligible after NAC was BCS in 42 cases (89.3%) and Ma in 5 (10.6%). Rates of patients’ adherence to the treatment proposed by the MDT were significantly better in the Group A (p = 0.02).ConclusionsOur results suggest that the MDT has a pivotal role in increasing the rates of breast conservation in women submitted to NAC.

Neoadjuvant Chemotherapy of Taxanes With or Without Anthracyclines in Different Molecular Subtypes of Breast Cancer: A Propensity Score Matching Study

PurposeTo compare the efficacy of taxane (T) based neoadjuvant chemotherapy (NAC) with T and anthracycline (A) based NAC in different molecular types of breast cancer (BC). MethodsWe retrospectively analyzed the date of NAC for BC from 20 hospitals in China from January 2010 to December 2020, 7870 cases were enrolled. The propensity score matching was used to equalize the baseline characteristics. Pathological complete response (pCR) rate, clinical response rate and breast-conserving rate were analyzed. ResultsThe efficacy of 2 regimens were similar in luminal A subtype. The breast-conserving rate was higher in T-based NAC in luminal B subtype (17.9% vs. 10.2%, P = .043).The pCR (T0/isN0M0) and tpCR (T0N0M0) rates in T-based NAC were higher than those in TA-based NAC for triple-negative subtype (pCR: 34.5% vs. 25.8%, P = .041, tpCR: 26.9% vs. 17.1%, P = .008). For HER2+(HR-) subtype, the pCR, and tpCR rates were higher in T-based NAC in insufficient anti-HER2 therapy (P < .05), and those were higher in TA-based NAC in dual-target anti-HER2 therapy (pCR: 69.2% vs. 53.8%, P = .254, tpCR: 61.5% vs. 42.3%, P = .165). For HER2+(HR+) breast cancer, both pCR and tpCR rates were higher in TA group, regardless of the adequacy of anti-HER2 treatment. ConclusionsT-based NAC could replace TA-based NAC for luminal A, luminal B, and triple-negative early-stage BC, but anthracyclines cannot be abandoned in HER2+ breast cancer. The development of anthracyclines with lower adverse reactions is one of the directions for the treatment of HER2+ breast cancer.

Impact of oncoplasty in increasing breast conservation rates Post neo-adjuvant chemotherapy.

The essential goal of neoadjuvant chemotherapy (NACT) is to downstage the primary tumor making it amenable for breast conservation surgery (BCS). However, since the safety of this surgery is paramount, post-NACT breast conservation rates remain low. As per the recommendation of the 2018 Early Breast Cancer Trialists' Collaborative Group (EBCTCG) overview of long-term post-NACT follow-up, we have devised a protocol for imaging, localization, rad-path analysis, and documentation of radiotherapy techniques to ensure the safety of post-NACT breast conservation. This is a retrospective cohort of 180 breast cancer patients who received NACT and were operated on by a single surgical oncologist from 2015 to 2020. After selection based on published guidelines, patients were treated with neoadjuvant systemic (chemo or hormone) therapy. In cases where primary tumors responded and reduced to 1-2 cm in size mid-NACT, the residual tumors were localized by clips under ultrasound guidance and calcification was wire localized. All patients were treated using appropriate surgical and oncoplastic techniques where indicated. Negative margins were ensured by intra-operative rad-path analysis. Adjuvant chemotherapy and radiotherapy were given as per protocol. In 81 cases that required mastectomy at presentation, we were able to achieve a 72.8% post-NACT BCS rate with the help of oncoplasty. Overall, 142 of 180 (80%) patients were treated with breast conserving surgery of which 80% (121 of 142) were oncoplasty. Margins were assessed on intra-operative frozen and re-excised in the same setting. No positive margins were reported in final histopath of 142 breast conservation procedures. Post-operative complication rates after breast conservation in the first year were at 17% (24 of 142 including two major complications). Patient reported outcomes were satisfactory with increased satisfaction for breast conservation compared with immediate breast reconstruction. Employing oncoplastic breast surgery (OBS) techniques following stringent protocols for accurate localization of the residual tumor, intra-operative rad-path analysis, and adjuvant treatments, we show successful breast conservation in 72.8% of our mastectomy-qualified patients after downstaging by NACT. We also report satisfactory outcomes for post-NACT surgery, patient-reported satisfaction, and survival.

Assessing trends in breast care surveillance metrics after implementing surgeon-specific tracking and performance reporting in a large, integrated cancer network.

There are few quality metrics and benchmarks specific to surgical oncology. Development of a surgeon-level performance metrics system based on peer comparisons is hypothesized to positively influence surgical decision-making. This study established a tracking and reporting system comprised of evidence and consensus-based metrics to assess breast care delivered by individual surgeons. Surgeons' performance is assessed by a surveillance tracking system of metrics pertaining to referrals and surgical elements. This retrospective analysis of prospectively collected breast care data reports on recurring 6-month and cumulative data from nine care locations from 2015 to 2021. Breast care was provided to 6659 patients by 41 surgeons. A total of 27 breast care metrics were evaluated over 7 years. Metrics with consistent, proficient results were retired after 18 months, including the rate of core biopsy, specimen orientation, and referrals to medical oncology, genetics, and fertility, among others. In clinically node-negative, hormone receptor-positive patients 70 years of age or older, the cumulative rate of sentinel lymph node (SLN) biopsy significantly decreased by 40% over 5.5 years (p<.001). The overall breast conservation rate for T0-T2 cancer increased 10% over 7 years. At the surgeon level, improvements were made in the median number of SLNs removed and in operative note documentation. Implementation of a surgeon-specific, peer comparison-based metric and tracking system has yielded substantive changes in breast care management. This process and governance structure can serve as a model for quantification of breast care at other institutions and for other disease sites.

Practice patterns in ongoing neoadjuvant ATNEC trial for patients with cT1-3N1M0 breast cancer: Response to neoadjuvant chemotherapy (NACT), targeted axillary dissection and breast conservation rates.

e12609 Background: Patients presenting with cT1-3N1M0 breast cancer often receive NACT to enable breast and/or axillary conservation. Targeted axillary dissection (TAD) (sentinel node biopsy (SNB) + removal of marked involved node) has been proposed to reduce the false negative rate of SNB after NACT in cN1 patients. In ATNEC, cT1-3N1M0 patients receive NACT followed by SNB/TAD. If the sentinel nodes (SN) have converted to benign (ypN0), patients are randomly assigned to Axillary Treatment vs no Axillary Treatment. Node marking is recommended in the study and sites are offered training to help them adopt node marking in a standardized way. Objectives: To prospectively evaluate the practice patterns and response to NACT, uptake of node marking, marked node identification rates and breast conservation rates in the ongoing UK ATNEC trial. The trial aims to recruit 1900 patients. Methods: Data for all patients who were randomized until 01-Feb-23 across 78 UK centers were included in these analyses. Patients were cT1-3N1M0 at presentation, received NACT and were found to have no residual nodal disease (ypN0) on SNB/TAD. Results: Among the 120 randomized patients (median age 54 [range 28-77] years) (median BMI 26.4 [range 17.6-51.1]), 53% (64) were post-menopausal, 78% (94) had breast conserving surgery (BCS) and 22% (26) mastectomy. At presentation, 14% (17) were T3, 64% (77) T2 and 20% (24) T1. 70% (84) had grade 3 tumors. 62% (74) were HER2 positive, 31% (37) triple negative (TNBC) and 9% (7) HER2 negative (ER or PgR positive). 54% (65) had an anthracycline and taxane based NACT and 36%(43) had platinum containing NACT. Median of 4 nodes [interquartile range 3-5] were removed during SNB/TAD. Of 109 patients with node marking data, the involved node was marked in 73% (80). The marked node was identified and removed in 95% (76/80), marked node was the SN in 88% (67/76). Of the 109 patients with data for breast tumor post NACT, 69% (75) had pathological complete response (pCR), 7% (8) DCIS only, 24% (26) invasive cancer. Of the 63 patients with complete breast tumor response on imaging, 17% (11) had residual DCIS/invasive cancer. 50% (21/42) of patients with partial response or stable breast tumor on imaging had no residual tumor on histology (ypT0). Of the 107 patients with data on post NACT axillary imaging, 14% (15) had partial or stable disease but pCR on histology. Conclusions: Majority of UK patients having NACT have HER2 positive or TNBC. Although 69% patients had a pCR (ypT0) in the breast, BCS rates remain low. Imaging has limited accuracy in predicting pCR after NACT. 3 in 4 patients randomized had their node marked, with a 95% intra-operative identification rate; demonstrating ATNEC has successfully rolled out node marking in the UK. Clinical trial information: NCT04109079 .

NRG-BR007: A phase III trial evaluating de-escalation of breast radiation (DEBRA) following breast-conserving surgery (BCS) of stage 1, HR+, HER2-, RS ≤18 breast cancer.

TPS623 Background: Approximately 50% of newly diagnosed invasive breast cancers are stage 1, with the majority being ER/PR-positive, HER2-negative. Genomic assays such as the Oncotype DX have identified patients (pts) with reduced risk of distant metastasis and without benefit from chemotherapy added to endocrine therapy, freeing them from excess toxicity. Genomic assays are also recognized as prognostic for in-breast recurrence (IBR) after BCS and could similarly allow de-escalation of adjuvant radiotherapy (RT). Reducing overtreatment is of interest to pts, providers, and payers. Methods: We hypothesize that BCS alone is non-inferior to BCS plus RT for in-breast recurrence and breast preservation in women intending endocrine therapy (ET) for stage 1 invasive breast cancer (ER &amp;/or PR positive, HER2-negative with an Oncotype DX Recurrence Score [RS] of ≤18). Stratification is by age (&lt;60; ≥60), tumor size (≤1 cm; &gt;1-2cm), and RS (&lt;11, 11-18). Pts are randomized post-BCS to Arm 1 with breast RT using standard methods (hypo- or conventional-fractionated whole breast RT with/without boost, or APBI) with ≥5 yrs of ET (tamoxifen or AI) or Arm 2 with ≥5 yrs of ET (tamoxifen or AI) alone. The specific regimen of ET in both arms is at the treating physician’s discretion. Eligible pts are stage 1: pT1 (≤2 cm), pN0, age ≥50 to &lt;70 yrs, s/p BCS with negative margins (no ink on tumor), s/p axillary nodal staging (SNB or ALND), ER &amp;/or PR positive (ASCO/CAP), HER2-negative (ASCO/CAP), and Oncotype DX RS of ≤18 (diagnostic core biopsy or resected specimen). Primary endpoint is in-breast recurrence (invasive breast cancer or DCIS). Secondary endpoints are breast conservation rate, invasive in-breast recurrence, relapse-free interval, distant disease-free survival, overall survival, patient-reported breast pain, patient-reported worry about recurrence, and adherence to ET. We assume a clinically acceptable difference in IBR of 4% at 10 yrs to judge omission of RT as non-inferior (10-yr event-free survival for RT group is 95.6% vs 91.6% for the omission of RT group). BR007 is powered to detect non-inferiority with 80% power and a one-sided α=0.025, assuming that there would be a ramp-up in accrual in the first two years (leveling off in Yrs 3-5); 1,670 pts (835 per arm) are required for randomization. Conservative loss to follow-up is 1% per yr. Some of the T1a pts screened may have Oncotype DX scores &gt;18, making them ineligible for the study. In the accrual process, 1,714 pts will be required to register to ensure that our final randomized cohort is 1,670 pts. Current accrual (02-08-2023) is 370 screened and 323 randomized (~87% of predicted accrual). Clinical trial information: NCT04852887 .

Efficacy, cardiotoxicity and factors affecting pathologic complete response of neoadjuvant chemotherapy with anthracycline-containing verses anthracycline-free regimens plus dual HER2 blockade for HER2-positive early-stage breast cancer: a retrospective study.

The aim of this study was to compare the efficacy, cardiotoxicity and factors affecting pathologic complete response (pCR) of neoadjuvant chemotherapy (NACT) regimen TCbHP (docetaxel/nab-paclitaxel, carboplatin, trastuzumab and pertuzumab) and AC-THP (doxorubicin, cyclophosphamide followed by docetaxel/nab-paclitaxel, trastuzumab and pertuzumab) for human epidermal growth factor receptor 2-positive (HER2+) early-stage breast cancer at a retrospective cohort. This retrospective study included the patients with HER2+ early-stage breast cancer who received NACT with the regimen TCbHP or AC-THP and then underwent surgery from 2019 to 2022. pCR rate and breast-conserving rate were calculated to evaluate the efficacy of the regimens. Left ventricular ejection fraction (LVEF) from echocardiograms and abnormal electrocardiographs (ECGs) were collected to evaluate the cardiotoxicity of the two regimens. Association between the characteristics of the breast cancer lesions by magnetic resonance imaging (MRI) and the pCR rate were also explored. A total of 159 patients were enrolled, including 48 patients in the AC-THP group and 111 patients in the TCbHP group. The pCR rate of the TCbHP group 64.0% (71/111) was significantly higher than that of for the the AC-THP group 37.5% (18/48) (P=0.002). Estrogen receptor (ER) status (P=0.011, OR: 0.437, 95% CI: 0.231-0.829), progesterone receptor (PR) status (P=0.001, OR: 0.309, 95% CI: 0.157-0.608) and IHC HER2 status (P=0.003, OR: 7.167, 95% CI: 1.970-26.076) were significantly correlated with the pCR rate. LVEF decreased at 6 and 12 months after treatment in the AC-THP group (P=0.024 and 0.040), which only decreased after 6 months of treatment in the TCbHP group (P=0.048). Post-NACT MRI characteristics including mass features (P<0.001) and enhancement type (P<0.001) were significantly associated with pCR rate. Early-stage HER2+ breast cancer treated with the TCbHP regimen has a higher pCR rate than the AC-THP group. The TCbHP regimen appears to have lower cardiotoxicity than the AC-THP regimen in terms of LVEF. Mass features and enhancement type at post-NACT MRI significantly associated with the pCR rate of breast cancer patients.

Quality indicators in surgery for cancer: not just the operation.

Quality indicators in surgery for cancer: not just the operation.

Neoadjuvant systemic therapy for breast cancer.

The role of neoadjuvant therapy in the management of breast cancer has evolved dramatically over the past few decades. Preoperative treatment has the potential to downstage tumours and improve breast conservation rates as well as reduce the morbidity of axillary surgery. Furthermore, the in vivo sensitivity of the primary tumour to systemic therapy may be assessed at the time of final pathology when treatment is administered before operation. Monitoring of treatment response provides important prognostic and predictive information, with a pathological complete response (pCR) being associated with improved oncological outcomes1. Adjuvant therapy may also be affected in patients with residual disease who do not attain a pCR2–4. Neoadjuvant therapy for breast cancer may involve chemotherapy or endocrine therapy. The focus of this review is neoadjuvant therapy for the primary tumour in the breast. Axillary management after neoadjuvant therapy has been discussed previously5–8 and is beyond the scope of this review.

Surgeon Factors Influencing Breast Surgery Outcomes: A Scoping Review to Define the Modern Breast Surgical Oncologist.

Modern breast surgical oncology incorporates many aspects of care including preoperative workup, surgical management, and multidisciplinary collaboration to achieve favorable oncologic outcomes and high patient satisfaction. However, there is variability in surgical practice and outcomes. This review aims to identify modifiable surgeon factors influencing breast surgery outcomes and provide a definition of the modern breast surgical oncologist. A systematic literature search with additional backward citation searching was conducted. Studies describing modifiable surgeon factors with associated breast surgery outcomes such as rates of breast conservation, sentinel node biopsy, re-excision, complications, acceptable esthetic outcome, and disease-free and overall survival were included. Surgeon factors were categorized for qualitative analysis. A total of 91 studies met inclusion criteria describing both modifiable surgeon factor and outcome data. Four key surgeon factors associated with improved breast surgery outcomes were identified: surgical volume (45 studies), use of oncoplastic techniques (41 studies), sub-specialization in breast surgery or surgical oncology (9 studies), and participation in professional development activities (5 studies). On the basis of the literature review, the modern breast surgical oncologist has a moderate- to high-volume breast surgery practice, understands the use and application of oncoplastic breast surgery, engages in additional training opportunities, maintains memberships in relevant societies, and remains up to date on key literature. Surgeons practicing in breast surgical oncology can target these modifiable factors for professional development and quality improvement.

Impact of adding pertuzumab to trastuzumab plus chemotherapy in neoadjuvant treatment of HER2 positive breast cancer patients: a multicenter real-life HER2PATH study

Aim To investigate the pathological complete response (pCR) achieved after neoadjuvant therapy with versus without adding pertuzumab (P) to trastuzumab (H) plus neoadjuvant chemotherapy (NCT) in HER2+ breast cancer (BC) patients in a real-life setting. Methods A total of 1528 female HER2+ BC patients who received NCT plus H with or without P were included in this retrospective real-life study. Primary endpoint was pCR rate (ypT0/Tis ypN0). Clinicopathological characteristics, event-free survival (EFS) time, and relapse rates were evaluated with respect to HER2 blockade (NCT-H vs. NCT-HP) and pCR. Results Overall, 62.2% of patients received NCT-H and 37.8% received NCT-HP. NCT-HP was associated with a significantly higher pCR rate (66.4 vs. 56.8%, p < 0.001) and lower relapse (4.5 vs. 12.2%, p < 0.001) in comparison to NCT-H. Patients with pCR had a significantly lower relapse (5.6 vs. 14.9%, p < 0.001) and longer EFS time (mean(SE) 111.2(1.9) vs. 93.9(2.7) months, p < 0.001) compared to patients with non-pCR. Patients in the NCT-HP group were more likely to receive docetaxel (75.0 vs. 40.6%, p < 0.001), while those with pCR were more likely to receive paclitaxel (50.2 vs. 40.7%, p < 0.001) and NCT-HP (41.5 vs. 32.1%, p < 0.001). Hormone receptor status and breast conservation rates were similar in NCT-HP vs. NCT-H groups and in patients with vs. without pCR. Invasive ductal carcinoma (OR, 2.669, 95% CI 1.596 to 4.464, p < 0.001), lower histological grade of the tumor (OR, 4.052, 95% CI 2.446 to 6.713, p < 0.001 for grade 2 and OR, 3.496, 95% CI 2.020 to 6.053, p < 0.001 for grade 3), lower T stage (OR, 1.959, 95% CI 1.411 to 2.720, p < 0.001) and paclitaxel (vs. docetaxel, OR, 1.571, 95% CI 1.127 to 2.190, p = 0.008) significantly predicted the pCR. Conclusions This real-life study indicates that adding P to NCT-H enables higher pCR than NCT-H in HER2+ BC, while pCR was associated with lower relapse and better EFS time.

Abstract OT1-12-01: A phase III trial evaluating De-escalation of Breast Radiation (DEBRA) following breast-conserving surgery (BCS) of stage 1, HR+, HER2-, RS ≤18 breast cancer: NRG-BR007

Abstract BACKGROUND: Approximately 50% of newly diagnosed breast cancers are stage 1, with the majority being ER/PR-positive, HER2-negative. Genomic assays such as Oncotype DX® have identified pts with reduced distant metastasis and without benefit from chemotherapy, freeing patients from excess toxicity. Also, these genomic assays are prognostic of local-regional recurrence (LRR). The de-escalation of therapy is of interest to pts, providers, and payers. Low risk, as identified by Oncotype and Mammaprint®, is associated with low LRR after BCS and breast radiotherapy (RT). METHODS: We hypothesize that BCS alone is non-inferior to BCS plus RT for ipsilateral breast recurrence (IBR) and breast preservation in women intending appropriate endocrine therapy (ET) for stage 1 (ER and/or PR positive, HER2-negative, with an Oncotype DX Recurrence Score [RS] of ≤18) breast cancer. Stratification is by age (&amp;lt; 60; ≥60), tumor size (≤1 cm; &amp;gt;1-2cm), and RS (&amp;lt; 11; 11-18). Pts are randomized post-BCS to Arm 1 with breast RT using standard methods (hypo- or conventional-fractionated whole breast RT with or without boost, APBI) plus 5 years of ET (tamoxifen or AI) or Arm 2 with 5 years of ET (tamoxifen or AI) alone. The specific regimen of ET in both arms is at the treating physician’s discretion. Eligible pts are stage 1: pT1 (2 cm), pN0, age ≥50 to &amp;lt; 70 years, s/p BCS with negative margins (no ink on tumor), s/p axillary nodal staging (SNB or ALND), ER and/or PR positive (ASCO/CAP), HER2-negative (ASCO/CAP), and have an Oncotype DX RS of ≤18 (diagnostic core biopsy or resected specimen). Primary endpoint is IBR. Secondary endpoints are breast conservation rate, invasive in-breast recurrence, recurrence-free interval, distant disease-free survival, overall survival, patient-reported breast pain, patient-reported worry about recurrence, and adherence to ET. We assume a clinically acceptable difference in IBR of 4% at 10 years to judge omission of RT as non-inferior (10-year event-free survival for RT group is 95.6% versus 91.6% for the omission-of-RT group). The study is designed to be able to detect non-inferiority with 80% power and a one-sided α=0.025, and assuming that there would be a ramp-up in accrual in the first two years of the study (leveling off in Years 3-5), 1,670 (835 per arm) patients are required to be randomized. Conservative loss to follow-up is 1% per year. Some of the T1a pts screened will have Oncotype DX scores &amp;gt;18, making them ineligible for the study. In the accrual process, pts will be required to register (1,714 patients) to ensure that our final randomized cohort is 1,670 pts. Accrual as of 6-30-2022 is 169 screened and 147 randomized. Contact information: Protocol: CTSU member website: https://www.ctsu.org. NRG Oncology Pgh Clinical Coordinating Dpt: 1-800-477-7227 or ccdPGH@NRGOncology.org. Support: U10CA180868, -180822, UG1CA189867. NCT04852887. Citation Format: Julia White, Reena S. Cecchini, Eleanor E. Harris, Eleftherios (Terry) Mamounas, Daniel Stover, Patricia A. Ganz, Reshma Jagsi, Carmen Bergom, Valérie Théberge, Mahmoud B. El-Tamer, Richard Zellars, Dean A. Shumway, Guang-Pei Chen, Stewart J. Anderson, Thomas B. Julian, Norman Wolmark, Wendy Rea. A phase III trial evaluating De-escalation of Breast Radiation (DEBRA) following breast-conserving surgery (BCS) of stage 1, HR+, HER2-, RS ≤18 breast cancer: NRG-BR007 [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 OT1-12-01.