Surgery For Invasive Breast Cancer Research Articles

Abstract PO4-27-03: Real-World Evidence: Impact of Margin Involvement on Overall Survival Following Breast Cancer Surgery – A Single-Center Analysis at Charité University Medical Center Berlin

Abstract Introduction: Limited data is available regarding the impact of margin involvement following surgery for early-stage breast cancer on distant recurrence and overall survival (OS). We therefore conducted a retrospective single-center analysis to provide further real-world evidence of margin status on OS. Methods: We systematically evaluated patients who underwent surgical intervention for early breast cancer or carcinoma in situ at Charité University Medical Center Berlin between 2006 and 2022. Our study cohort included individuals with a minimum follow-up period of 6 months and documented margin status. Patients with secondary tumors were excluded from this comprehensive analysis. Results: In our analysis, we included a total of 3767 patients, with a median follow-up duration of 72.2 months. Among these, 3443 patients underwent surgery for invasive breast cancer, while 324 patients underwent surgery for carcinoma in situ. The median overall survival (OS) for the entire cohort was 63.7 months. Specifically, patients who achieved clear margins after primary surgery exhibited a median OS of 63.5 months (n=3068), and those with free margins after secondary surgery had a median OS of 65.2 months (n=610). Conversely, patients with definitively involved margins experienced a shorter median OS of 58.6 months (n=89). The multivariate analysis revealed a statistical trend toward adverse survival outcomes for patients with definitive involved margins (Hazard Ratio 1.55; 95% CI: 0.93-2.56; p=0.090), with no statistically significant difference observed between clear margins following primary or secondary surgery. Notably, patients who underwent breast-conserving surgery demonstrated a significantly improved OS (HR 0.45; 95% CI 0.37-0.45; p< 0.001). Higher rates of margin involvement were observed in patients with hormone receptor-positive tumors and carcinoma in situ, while lower rates were noted in triple-negative breast cancer and after neoadjuvant chemotherapy. Implication: Our findings suggest that involved margins may be associated with a limited overall survival. Notably, patients who underwent breast-conserving therapy exhibited more favorable outcomes in our analysis, underscoring the oncologic safety of this procedure. Citation Format: Maximilian Heinz Beck, Karoline Weiler, Sophia Ossmann, Verena Kiver, Jens-Uwe Blohmer. Real-World Evidence: Impact of Margin Involvement on Overall Survival Following Breast Cancer Surgery – A Single-Center Analysis at Charité University Medical Center Berlin [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 PO4-27-03.

Evaluating the feasibility and acceptability of an adapted fencing intervention in breast cancer surgery post-operative care: the RIPOSTE pilot randomized trial.

Adapted physical activity programs have shown promising results in reducing the physical, social and psychological side effects associated with breast cancer, but the extent to which they can be effectively adopted, implemented and maintained is unclear. The aim of this study is to use the framework to guide the planning and evaluation of programs according to the 5 following keys: Reach, Effectiveness, Adoption, Implementation and Maintenance (RE-AIM) framework to evaluate a fencing program under the French acronym RIPOSTE (Reconstruction, Image de soi, Posture, Oncologie, Santé, Thérapie, Escrime) literally in English (Reconstruction, Self-Image, Posture, Oncology, Health, Therapy, Fencing). This program is an innovative intervention focused on improving the quality of life (QoL) of breast cancer surgery patients through fencing. A convergent mixed methods pilot study was conducted to preliminary evaluate the different RE-AIM dimension of the pilot program. Twenty-four participants who have just undergone surgery for invasive breast cancer were randomly allocated in two groups: one group started immediately after their inclusion (Early RIPOSTE group) and the other started 3 months following their inclusion (Delayed RIPOSTE group). Participants answered a questionnaire at inclusion and at the end of the program on QoL, shoulder functional capacity, fatigue, anxiety-depression and physical activity. RIPOSTE program was able to reach mainly young and dynamic participants, attracted by the originality of fencing and keen to improve their physical condition. Regarding effectiveness, our results suggest a trend to the improvement of QoL, shoulder functional capacity, fatigue and anxiety-depression state, even without any significant differences between the Early RIPOSTE group and the Delayed RIPOSTE group. The cooperation, exchanges and cohesion within the group greatly facilitated the adoption of the program, whereas interruptions during school vacations were the main barriers. The intervention was moderately well implemented and adherence to the protocol was suitable. RIPOSTE is an acceptable and effective program for involving breast cancer survivors in physical activity, that needs to be tested at a larger scale to investigate its effectiveness, but has the potential to be transferred and scaled up worldwide.

Comparison of long-term oncologic outcomes of central lumpectomy and conventional breast-conserving surgery for invasive breast cancer: propensity score matching analysis.

Central lumpectomy (CL) is a breast-conserving surgical (BCS) technique that involves excision of the nipple-areolar complex with breast tumor in centrally located breast cancers. We aimed to investigate the long-term clinical outcomes of CL in comparison with conventional BCS (cBCS). Patient records who underwent BCS with clear resection margins for invasive breast cancer between 2004 and 2018 were retrospectively reviewed. Of the total 6,533 patients, 106 (1.6%) underwent CL. Median follow-up duration was 73.4months. 1:3 propensity score matching (PSM) and inverse probability of treatment weighting (IPTW) were used to minimize selection bias. The CL group showed a significantly higher ipsilateral breast tumor recurrence (IBTR) rate than the cBCS group (10-year IBTR rate: 5.8% vs. 3.1%, p = 0.004), even after adjusting for other variables (hazard ratio (HR), 2.65; 95% confidence interval (CI), 1.07-6.60, p = 0.048). However, there were no significant differences observed inregional recurrence, distant metastasis, oroverall survival rates between the two groups. Both PSM and IPTW analyses showed significantly higher IBTR in the CL group (PSM HR, 3.27; 95% CI, 0.94-11.36; p = 0.048 and IPTW HR, 4.66; 95%CI, 1.85-11.77; p < 0.001). Lastly, when analyzing 2,213 patients whose tumors were located within 3cm of the nipple, the CL group showed a significantly higher IBTR than the cBCS group before and after PSM. CL was associated with a higher rate ofIBTR compared to cBCS, while other survival outcomes were comparable. For centrally located tumors, CL may be considered for patients preferring breast preservation. However, higher risk for IBTR should be informed and careful surveillance may be necessary during the early post-operative follow-up periods.

Effect of high-dose radiation therapy on positive margins after breast-conserving surgery for invasive breast cancer.

Positive margins after breast-conserving surgery are associated with poor oncological outcomes and warrant additional surgery. This study aimed to evaluate the effectiveness of high-dose radiation therapy for positive margins by comparing local recurrence between patients with positive and negative margins. We retrospectively evaluated 550 patients treated with adjuvant radiation therapy after breast-conserving surgery for invasive breast cancer between 2013 and 2019. The total equivalent dose in 2Gy fractions (EQD2) to the tumor bed ranged from 65.81 to 66.25Gy for positive margins and 59.31-61.81Gy for negative margins. The differences in local recurrence between the positive and negative margin groups were analyzed. After a median follow-up of 58 months, the crude local recurrence rate was 7.3% in the positive margin group (n=55) and 2.4% in the negative margin group (n=495). Positive margins were associated with higher local recurrence without statistical significance in the entire cohort (p=0.062). Among patients aged <60 years, those with positive margins had a significantly lower 5-year local recurrence-free survival rate than those with negative margins (89.16% vs. 97.57%, respectively; p=0.005). In contrast, there was no significant difference in the 5-year local recurrence-free survival rate between patients with positive and negative margins among those aged ≥60 years (100.00% vs. 94.38%, respectively; p=0.426). In this study, positive margins were not associated with poor local control in older patients after a high-dose boosts. Further prospective studies are needed to verify our findings.

Patterns and Longitudinal Changes in The Practice of Breast Cancer Radiotherapy in Korea: Korean Radiation Oncology Group 22-01

To analyze contemporary practice patterns in breast cancer radiotherapy (RT) and to assess longitudinal changes therein over 5 years in Korea. A nationwide survey was conducted among board-certified radiation oncologists in Korea by the Division for Breast Cancer of the Korean Radiation Oncology Group in March 2022. The survey consisted of 44 questions related to six domains: hypofractionated (HypoFx) whole breast RT, accelerated partial breast RT (APBI), regional nodal irradiation (RNI), RT for ductal carcinoma in situ (DCIS), postmastectomy RT (PMRT), and tumor bed boost. In total, 70 radiation oncologists from 61 of 101 (60%) institutions participated in the survey. HypoFx RT was used by 62 respondents (89%), which has significantly increased from 36% in 2017. The HypoFx RT was commonly administered at 40-42.5 Gy in 15-16 fractions. APBI was used by 12 respondents (17%), which has increased from 5% in 2017. The use of RNI did not change significantly: ≥ pN2 (6%), ≥ pN1 (33%), and ≥ pN1 with pathological risk factors (61%). However, the indications for use of internal mammary lymph node (IMN) irradiation have expanded. In particular, the rates of routine treatment of IMN (11% from 6% in 2017) and treatment in cases of ≥ pN2 (27% from 14% in 2017) have doubled; however, the rate of treatment for only IMN involvement, identified on imaging, has decreased to 31% from 47% in 2017. With regard to DCIS, the use of hypoFx RT increased to 75% from 25%, and the rate of omission on of RT after breast-conserving surgery decreased to 38% from 48% in 2017. The use of hypoFx RT for PMRT also increased to 36% from 8% in 2017. The adoption of HypoFx RT after breast-conserving surgery in invasive breast cancer and DCIS has increased significantly, whereas that for PMRT has increased moderately, compared to 2017. Further studies are required to determine the optimal use of RNI.

Impact of general anaesthesia on breast cancer survival: a 5-year follow up of a pragmatic, randomised, controlled trial, the CAN-study, comparing propofol and sevoflurane.

Anaesthesia may impact long-term cancer survival. In the Cancer and Anaesthesia study, we hypothesised that the hypnotic drug propofol will have an advantage of at least five percentage points in five-year survival over the inhalational anaesthetic sevoflurane for breast cancer surgery. From 2118 eligible breast cancer patients scheduled for primary curable, invasive breast cancer surgery, 1764 were recruited after ethical approval and individual informed consent to this open label, single-blind, randomised trial at four county- and three university hospitals in Sweden and one Chinese university hospital. Of surveyed patients, 354 were excluded, mainly due to refusal to participate. Patients were randomised by computer at the monitoring organisation to general anaesthesia maintenance with either intravenous propofol or inhaled sevoflurane in a 1:1 ratio in permuted blocks. Data related to anaesthesia, surgery, oncology, and demographics were registered. The primary endpoint was five-year overall survival. Data are presented as Kaplan-Meier survival curves and Hazard Ratios based on Cox univariable regression analyses by both intention-to-treat and per-protocol. EudraCT, 2013-002380-25 and ClinicalTrials.gov, NCT01975064. Of 1764 patients, included from December 3, 2013, to September 29, 2017, 1670 remained for analysis. The numbers who survived at least five years were 773/841 (91.9% (95% CI 90.1-93.8)) in the propofol group and 764/829 (92.2% (90.3-94.0)) in the sevoflurane group, (HR 1.03 (0.73-1.44); P=0.875); the corresponding results in the per-protocol-analysis were: 733/798 (91.9% (90.0-93.8)) and 653/710 (92.0% (90.0-94.0)) (HR=1.01 (0.71-1.44); P=0.955). Survival after a median follow-up of 76.7 months did not indicate any difference between the groups (HR 0.97, 0.72-1.29; P=0.829, log rank test). No difference in overall survival was found between general anaesthesia with propofol or sevoflurane for breast cancer surgery. Swedish Research Council; Uppsala-Örebro Regional Research Council; Västmanland Regional Research Fund; Västmanland Cancer Foundation; Stig and Ragna Gohrton Foundation; Birgit and Henry Knutsson Foundation.

Abstract GS4-04: Population-based Estimates of contralateral Breast Cancer Risk among Carriers of Germline Pathogenic Variants in ATM, BRCA1, BRCA2, CHEK2, and PALB2

Abstract Purpose To estimate the risk of contralateral breast cancer (CBC) among women in the general population with germline pathogenic variants (PVs) in ATM, BRCA1, BRCA2, CHEK2, and PALB2. Methods Among 15,104 prospectively followed women within the CARRIERS study treated with ipsilateral surgery for invasive breast cancer, a subset of 14,237 women were identified from population-based studies. The risk of CBC was estimated for PV carriers in each gene compared to women without PVs in a multivariate proportional hazard regression analysis accounting for the competing risk of death and adjusting for patient and tumor characteristics. The primary analyses focused on the overall cohort and on women from the general population. Secondary analyses examined associations by race/ethnicity, age at primary breast cancer diagnosis, menopausal status, and tumor estrogen receptor status. Results Germline BRCA1, BRCA2, and CHEK2 PV carriers with breast cancer were at significantly elevated risk (Hazard ratio ≥ 1.9, p&amp;lt; 0.05) of CBC, whereas only the PALB2 PV carriers with ER-negative breast cancer had elevated risks. In contrast, ATM PV carriers did not have significantly increased CBC risks. African American PV carriers had similarly elevated risks of CBC as non-Hispanic White PV carriers. Among premenopausal women, the 15-year cumulative incidence of CBC was &amp;gt;20% for BRCA1, BRCA2 and CHEK2 PV carriers with breast cancer, and for PALB2 PV carriers with ER-negative breast cancer. The 15-year cumulative incidence of CBC among postmenopausal PV carriers was &amp;lt; 20% for PV carriers in any of the 5 genes. Conclusions Women diagnosed with breast cancer and known to carry germline PVs in BRCA1, BRCA2, CHEK2, or PALB2 are at substantially increased risk of CBC and may benefit from enhanced surveillance and risk-reduction strategies. Citation Format: Siddhartha Yadav, Nicholas J. Boddicker, Jie Na, Eric C. Polley, Chunling Hu, Steven N. Hart, Rohan D. Gnanaolivu, Nicole Larson, Carolyn Dunn, Susan Holtegaard, Huaizhi Huang, Lauren R. Teras, Alpa V. Patel, James V. Lacey Jr., Susan Neuhausen, Leslie Bernstein, Elena Martinez, Christopher Haiman, Fei Chen, Kathryn Ruddy, Janet Olson, Esther John, Allison W. Kurian, Dale P. Sandler, Katie M. O’Brien, Jack A. Taylor, Clarice R. Weinberg, Hoda Anton-Culver, Argyrios Ziogas, Gary R. Zirpoli, David E. Goldgar, Katherine L. Nathanson, Susan Domchek, Julie R. Palmer, Jeffrey Weitzel, Peter Kraft, Fergus J. Couch. Population-based Estimates of contralateral Breast Cancer Risk among Carriers of Germline Pathogenic Variants in ATM, BRCA1, BRCA2, CHEK2, and PALB2 [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 GS4-04.

Abstract P1-05-21: Change in breast cancer detection method, stage at diagnosis and treatment during the COVID-19 Pandemic: 2019-2021

Abstract Objective: Identify changes in breast cancer detection method, stage at diagnosis and treatment prior to, during and after stay-at-home orders and restricted health care access due to COVID-19. Methods: Statistical comparison of detection method (patient (PtD), mammography (MamD) or other), Anatomic TNM Stage 8 (0-IV) and invasive BC treatment change over time by three time periods (time 1: 2019+Q1 2020; time 2: Q2-Q4 2020; time 3: 2021) using chi-square analysis in an institutional retrospective cohort of first primary breast cancer (BC) patients (n=1799), years 2019-2021. Results: In the years prior to the study, 2016-2019, there was no difference in detection method or stage at diagnosis by year with 682 to 733 newly diagnosed BC annually (p=.462). In 2020 (n=535) and 2021 (n=582) annual diagnosed cases dropped 22% and 15% from 2019 levels. Compared to time 1, time 2 MamD BC dropped significantly (64% to 58%) with a subsequent increase in MamD BC to 70% in time 3 (p &amp;lt; .001) creating a U-shaped curve for MamD over time. PtD BC increased in time 2 from 30% to 36% but declined in time 3 to 25% (p &amp;lt;.001). Concurrently, stage at diagnosis shifted from time 1 to time 2 with stage 0 and I declining [stage 0: 21% to 16%, stage I: 40% to 38%] and stage II and IV increasing [stage II: 28% to 33%, stage IV: 2% to 4% stage IV] (p&amp;lt;.001). Subsequently in 2021 stage shifted again with an increase in stage 0 to 22% and stage I to 45% and a decline in stage II (33% to 24%), III (9% to 7%) and IV (4% to 2%) (p&amp;lt;.001). Combining stage 0 and I, the percentage of lower stage BC declined from 61% to 54% and increased to 67% in time 3 (2021) when health services became more readily accessible. There was no change in type of surgery for invasive breast cancer (stage I-III, n=1386) with equivalent numbers of breast conserving surgery (58%), subcutaneous mastectomy (24%) and mastectomy (18%) over the time period. Chemotherapy treatment rates for invasive BC did not change (38%). Radiation therapy increased from 66% (time 1: 2019+Q1 2020) to 73% (time 2: Q2-Q4 2020) then back to 64% in time 3: 2021 (p=.007) independent of surgery type but concordant with an increase in stage IA and stage IIB BC among invasive breast cancer cases in time 2: Q2-Q4 2020 (p&amp;lt;.001). Likewise, neoadjuvant therapy increased and then declined from 33% to 38% to 29% from time 1 to time 3 (p&amp;lt;.001). Conclusions: Number of diagnosed BC cases fell after the first quarter of 2020 during the time of COVID-19 related shut downs and decreased access to health services. During the Q2-Q4 2020 time period mammography detected BC declined with a relative increase in patient detected breast cancer. When mammography detection declined, BC stage at diagnosis shifted to higher stage concurrent with increased rates of radiation and neoadjuvant therapy. In 2021, the relative increase in mammography detected BC indicates a return to more normal screening patterns with a catch up for screening lost in the prior year due to access limitations. In the third time period: 2021, with the return to prior levels of mammography detected breast cancer, stage shifted back to pre-pandemic expected distribution and the excess treatment with radiation and neoadjuvant therapy declined to previously observed levels. Although the changes in detection method, stage and treatment did not persist they were statistically significant and could represent a need for re-establishing pre-pandemic screening behavior. Table 1 Detection Method by COVID Pandemic Diagnosis Time Periods: 2019-2021 (N=1799). Citation Format: Judith A. Malmgren, Mary Atwood, Henry Kaplan. Change in breast cancer detection method, stage at diagnosis and treatment during the COVID-19 Pandemic: 2019-2021 [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 P1-05-21.

Contralateral Breast Cancer Risk Among Carriers of Germline Pathogenic Variants in ATM, BRCA1, BRCA2, CHEK2, and PALB2.

To estimate the risk of contralateral breast cancer (CBC) among women with germline pathogenic variants (PVs) in ATM, BRCA1, BRCA2, CHEK2, and PALB2. The study population included 15,104 prospectively followed women within the CARRIERS study treated with ipsilateral surgery for invasive breast cancer. The risk of CBC was estimated for PV carriers in each gene compared with women without PVs in a multivariate proportional hazard regression analysis accounting for the competing risk of death and adjusting for patient and tumor characteristics. The primary analyses focused on the overall cohort and on women from the general population. Secondary analyses examined associations by race/ethnicity, age at primary breast cancer diagnosis, menopausal status, and tumor estrogen receptor (ER) status. Germline BRCA1, BRCA2, and CHEK2 PV carriers with breast cancer were at significantly elevated risk (hazard ratio > 1.9) of CBC, whereas only the PALB2 PV carriers with ER-negative breast cancer had elevated risks (hazard ratio, 2.9). By contrast, ATM PV carriers did not have significantly increased CBC risks. African American PV carriers had similarly elevated risks of CBC as non-Hispanic White PV carriers. Among premenopausal women, the 10-year cumulative incidence of CBC was estimated to be 33% for BRCA1, 27% for BRCA2, and 13% for CHEK2 PV carriers with breast cancer and 35% for PALB2 PV carriers with ER-negative breast cancer. The 10-year cumulative incidence of CBC among postmenopausal PV carriers was 12% for BRCA1, 9% for BRCA2, and 4% for CHEK2. Women diagnosed with breast cancer and known to carry germline PVs in BRCA1, BRCA2, CHEK2, or PALB2 are at substantially increased risk of CBC and may benefit from enhanced surveillance and risk reduction strategies.

Mammoplastic surgery in invasive breast cancer

Mammoplastic surgery in invasive breast cancer

The Accuracy of Mammography, Ultrasound, and Magnetic Resonance Imaging For the Measurement of Invasive Breast Cancer With Extensive Intraductal Components

BackgroundThe precise preoperative evaluation of radiologic tumor size with extensive intraductal component (EIC) is important. This study compared the accuracy of mammography, ultrasound (US), and magnetic resonance imaging (MRI) to measure invasive breast cancer with EIC. MethodsBetween 2007 and 2012, we collected data from 6816 patients who underwent surgery for invasive breast cancer at our institution. We reviewed the postoperative surgical reports of the tumors, in which the invasive tumor size and EIC were measured separately. Finally, we included 370 women who underwent preoperative mammography, US, and MRI. Each modality was retrospectively reviewed to measure the size of invasive breast cancer with EIC. The reference standard was surgical pathologic size and the accuracies of the image were evaluated. ResultsSpearman's correlation coefficient for the size of invasive cancer with EIC was good between MRI (r = 0.741) and pathology, and moderate between mammography (r = 0.661) or US (r = 0.514) and pathology. Both mass and nonmass lesions showed good correlations (intraclass correlation coefficient [ICC] = 0.672 and 0.612, respectively) in MRI. Furthermore, the subgroup of tumors without microcalcifications showed a higher correlation with MRI (ICC = 0.796) than with mammography (ICC = 0.620). However, the subgroup with microcalcifications showed a good correlation with mammography (ICC = 0.702) compared to MRI (ICC = 0.680) and US (ICC = 0.532). ConclusionThe lesion on mammography, US, and MRI reflected preoperative size of invasive cancer with EIC. MRI shows a higher correlation than mammography and US. However, cancer with calcifications of mammography shows a more accurate size than MRI or US.

Width of excision margins after breast conserving surgery for invasive breast cancer and distant recurrence and survival

One premise of cancer treatment is that if a tumour is cut out but tumour cells remain present or close to the edges (of the cut), the risk of cancer...

Associations of hospital volume and hospital competition with short-term, middle-term and long-term patient outcomes after breast cancer surgery: a retrospective population-based study

ObjectivesFor oncological care, there is a clear tendency towards centralisation and collaboration aimed at improving patient outcomes. However, in market-based healthcare systems, this trend is related to the potential trade-off...

Abstract P3-18-10: Current options and future perspectives for breast margin assessment in clinical practice

Abstract Background: Ensuring negative margins at the time of breast conserving surgery for invasive breast cancer or ductal carcinoma in situ is necessary to minimize the chance of local recurrence and avoid re-excisions that cause patient concern and may delay adjuvant therapy. However, about 25% of women who have lumpectomy have a second surgery to remove residual disease, suggesting an ongoing need for improved methods of intraoperative margin assessment. This study aimed to perform a contemporary review of methods of intraoperative margin assessment during breast conservation surgery. Methods: A review of the scientific literature from 2009 to 2021 comprising 62 manuscripts of the current and proposed. intraoperative techniques for breast margin assessment during breast conservation surgery was conducted via PubMed and Google Scholar. The methods assessed were grouped into 10 categories based on the technology employed: bioimpedance/radiofrequency, high-resolution imaging, optical imaging, mass spectrometry, magnetic-resonance imaging, 2D/3D specimen CT, X-ray, multimodal optical microscopy, pharmacologic and pathological margin assessment. All technologies were reviewed for overall effectiveness in lowering re-excision rates derived from their respective advantages, limitations, sensitivity, and specificity. Results: Overall, 8 current and 7 technologies under development were assessed (Table 1). Frozen section and cytology yielded the highest diagnostic accuracy; however, these can be time-consuming, resource-intensive, and have limited sampling points. Conversely, 2D specimen CT provides rapid results but is limited by relatively low sensitivity. Future technologies such as optical coherence tomography showed promising results in demonstrating higher diagnostic accuracy for lumpectomy and margin shaves, but remain to be proven in clinical practice. Conclusion: Intraoperative margin assessments can lower final positive margins and subsequent re-excisions rates. A number of current and upcoming technologies that assess margin status range in their respective efficacies and limitations. There remains demand for improved margin assessment at the time of breast conserving surgery, but which technologies will become standard of care remains, at present, unclear. Table 1.Methods of intraoperative margin assessmentMethod:Brand:Sensitivity:Specificity:Source:Bioimpedence• ClearEdge™87.3%75.6%Dixon et al. 2016• MarginProbe75.2%70-87%Schanabel et al., 2014Cytology:• Imprint72%97%Esbona &amp; Zhanhai 2012; Qui et al., 2018Frozen Section–83%95%Schmidt et al, 2020; Schwarz &amp; Schmidt, 2020Mass Spectrometry• iKnife93.4-94.7%94.7-96.2%St. John et al., 2017• MasSpec Pen83-95%95-100%Garza et al., 2020Multimodal optical microscopy• fluorescence imaging combination withRCM/OCT subsystemTBDTBDScimone et al., 2021MRI• ClearSight™93%92%Moshe et al., 2016Optical Coherence Tomography (OCT)• OTIS™96%92%Mojahed et al., 2020; Schmidt et al. 2020Pharmacology• Bevacizumab98%79%Koch et al., 2017• Lumicell2-3D specimen CT• Mozart®93%78%Black et al., [poster]• Faxitron78.6-85.6%100%Emmadi &amp; Wiley 2012; Bathla et al. 2011• MicroCT56%100%Qiu et al. 2018X-ray• XPCI83%83%Massimi et al. 2021 Citation Format: Huma Javaid, Ivan Marin, Jessica Montalvan, Logan Healy, Brian Menegaz, Cary Hsu, Eric Silberfein, Elizabeth Bonefas, Stacey A. Carter, Alastair M. Thompson. Current options and future perspectives for breast margin assessment in clinical practice [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 P3-18-10.

Diffusion-weighted MRI for predicting pathologic response to neoadjuvant chemotherapy in breast cancer: evaluation with mono-, bi-, and stretched-exponential models

BackgroundTo investigate the performance of diffusion-weighted (DW) MRI with mono-, bi- and stretched-exponential models in predicting pathologic complete response (pCR) to neoadjuvant chemotherapy (NACT) for breast cancer, and further outline a predictive model of pCR combining DW MRI parameters, contrast-enhanced (CE) MRI findings, and/or clinical-pathologic variables.MethodsIn this retrospective study, 144 women who underwent NACT and subsequently received surgery for invasive breast cancer were included. Breast MRI including multi-b-value DW imaging was performed before (pre-treatment), after two cycles (mid-treatment), and after all four cycles (post-treatment) of NACT. Quantitative DW imaging parameters were computed according to the mono-exponential (apparent diffusion coefficient [ADC]), bi-exponential (pseudodiffusion coefficient and perfusion fraction), and stretched-exponential (distributed diffusion coefficient and intravoxel heterogeneity index) models. Tumor size and relative enhancement ratio of the tumor were measured on contrast-enhanced MRI at each time point. Pre-treatment parameters and changes in parameters at mid- and post-treatment relative to baseline were compared between pCR and non-pCR groups. Receiver operating characteristic analysis and multivariate regression analysis were performed.ResultsOf the 144 patients, 54 (37.5%) achieved pCR after NACT. Overall, among all DW and CE MRI measures, flow-insensitive ADC change (ΔADC200,1000) at mid-treatment showed the highest diagnostic performance for predicting pCR, with an area under the receiver operating characteristic curve (AUC) of 0.831 (95% confidence interval [CI]: 0.747, 0.915; P < 0.001). The model combining pre-treatment estrogen receptor and human epidermal growth factor receptor 2 statuses and mid-treatment ΔADC200,1000 improved the AUC to 0.905 (95% CI: 0.843, 0.966; P < 0.001).ConclusionMono-exponential flow-insensitive ADC change at mid-treatment was a predictor of pCR after NACT in breast cancer.

Abstract ES2-2: Evolving opportunities to personalize radiation decisions - Guiding decisions to omit radiation after breast conserving surgery for invasive breast cancer

Abstract Much as the development of molecularly based signatures (OncotypeDx®, MammaPrint®, ProSigna™, etc.) has revolutionized the decision-making process surrounding the need for adjuvant chemotherapy in women with early stage breast cancer, the development of prognostic and predictive signatures to determine the need and efficacy of radiation for women with breast cancer holds similar promise. While preliminary efforts to develop these signatures has been encouraging, much work remains in order to successfully translate these signatures into the clinic. In this educational session, we will review the current status of genomic-based signatures for radiation decision making. We will also review the barriers to clinical adoption and the molecularly stratified trials testing these signatures for treatment omission. Ultimately, for any of these tests to be translated into the clinic it will require demonstration of their accuracy and reproducibility as a test and perhaps more importantly, demonstration of clinical utility and an ability to improve outcomes for women with breast cancer. While not yet realized, the ongoing development of these signatures holds much promise as the field seeks to finally realize “personalized medicine” as it relates to radiation treatment for women with breast cancer. Citation Format: C Speers. Evolving opportunities to personalize radiation decisions - Guiding decisions to omit radiation after breast conserving surgery for invasive breast cancer [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr ES2-2.

218P - Oncological impact of re-excision for positive margin status after breast conserving surgery in invasive breast cancer

BackgroundPositive margin of breast-conserving surgery (BCS) is well known to be a risk factor for ipsilateral breast tumor recurrence (IBTR). SSO/ASTRO guidelines defined ink on invasive cancer or DCIS as positive margin and recommend considering doing re-excision of the site of positive margin. However, whether re-excision can reduce IBTR has not been fully investigated yet. The aim of this study was to retrospectively assess the oncological impact of re-excision for positive margin status after BCS in invasive breast cancer. MethodsThe subjects were 196 invasive breast cancer patients who underwent BCS, and who were found to have positive margin. Of the 196 patients, 55 underwent re-excision after initial BCS (group A), and 139 did not (group B). We analyzed IBTR free survival in each group and evaluated the predictors for IBTR and overall survival (OS) using Cox proportional hazards modeling. ResultsOf the 196 patients, 188 (96%) underwent adjuvant radiotherapy and 24 of 55 re-excision (43%) identified residual disease. There was no significant difference in 10-year IBTR free survival between group A and group B (94.4% versus 93.8%; P=0.58). In a multivariate analysis, re-excision was not associated with IBTR and OS, while younger age, lack of adjuvant radiotherapy, and invasive component of margin status were independent predictors of IBTR. ConclusionsIn our retrospective study, re-excision for positive margin after initial BCS in invasive breast cancer does not contribute to prevent IBTR and may not translate into improved OS. Further treatment should be considered when patient was younger and margin status was invasive component. Legal entity responsible for the studyKenjiro Jimbo. FundingHas not received any funding. DisclosureAll authors have declared no conflicts of interest.

Does Breast Density Increase the Risk of Re-excision for Women with Breast Cancer Having Breast-Conservation Therapy?

Women with dense breasts may have less-accurate preoperative evaluation of extent of disease, potentially affecting the achievement of negative margins. The goal of this study is to examine the association between breast density and re-excision rates in women having breast-conserving surgery for invasive breast cancer. Women with stage I/II invasive breast cancer treated with breast-conserving surgery between 1/1/2014 and 10/31/2014 were included. Breast density was assessed by two radiologists. The association between breast density and re-excision was examined using logistic regression. Seven hundred and one women were included. Overall, 106 (15.1%) women had at least one re-excision. Younger age at diagnosis was associated with increased breast density (p < 0.001). On univariable analysis, increased breast density was associated with significantly increased odds of re-excision (odds ratio [OR] 1.38, 95% confidence interval [CI] 1.04-1.83), as was multifocal disease, human epidermal growth factor receptor 2 (HER2) positive status, and extensive intraductal component (EIC) (all p < 0.05). On multivariable analysis, breast density remained significantly associated with increased odds of re-excision (OR 1.37, 95% CI 1.00-1.86), as did multifocality and EIC. HER2 positive status was not significantly associated with re-excision on multivariable analysis. Women with dense breasts are more likely to need additional surgery (re-excision after breast-conserving surgery), but increased breast density did not adversely affect disease-free survival in our study. Our findings support the need for further study in developing techniques that can help decrease re-excisions for women with dense breasts who undergo breast-conserving surgery.

Impact of Resident and Fellow Participation on Surgical Outcomes in Breast Conserving Surgery for Invasive Breast Cancer

Few studies examine the impact of surgical trainee involvement on tumor-free margins in breast conserving surgery (BCS). Our objective was to investigate the impact of resident and fellow involvement on positive margins rates following BCS for invasive breast cancer (BC). We identified female patients who had BCS for BC between January 2005 to December 2015. Tertiary care hospital. Around 1089 patients were identified from a prospectively maintained database. Of 1089 patients, mean age was 63 (range 43-99) years. Around 768 patients (70.1%) required preoperative localization, and 328 patients (29.9%) had a palpable cancer. Nonpalpable cancers had a smaller volume of specimen tissue excised (p = 0.0005) compared to palpable cancers, and no significant difference was observed in the positive margin rate between the nonpalpable group compared to the palpable group (24.7% nonpalpable vs. 25.3% palpable, p = 0.88). Nonpalpable cancer positive margin rates were 23.9% (n = 102/427) for cases performed by an attending surgeon, 25.0% (n = 15/60) with a junior resident (PGY 2-3), 28.6% (n = 8/28) with a senior resident (PGY 4-5), and 25.7% (n = 65/253) with a fellow, which were not statistically significant (p = 0.89). Palpable cancer positive margin rates were 27.6% (n = 47/170) for cases performed by an attending, 13.9% (n = 5/36) with an intern (PGY-1), 40.9% (n = 9/22) with a junior resident, 0% (n = 0/8) with a senior resident, and 23.9% (n = 22/92) with a fellow, which were also not significantly different (p = 0.07). Resident and fellow participation in BCS for BC does not appear to impact the rate of positive margins.

Dynamic contrast-enhanced and diffusion-weighted MRI of invasive breast cancer for the prediction of sentinel lymph node status.

Although sentinel lymph node biopsy (SLNB) is the current standard for identifying lymph metastasis in breast cancer patients, there are complications of SLNB. To evaluate preoperative dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and diffusion-weighted imaging (DWI) of invasive breast cancer for predicting sentinel lymph node metastasis. Retrospective. In all, 309 patients who underwent clinically node-negative invasive breast cancer surgery FIELD STRENGTH/SEQUENCE: 3.0T, DCE-MRI, DWI. We collected clinicopathologic variables (age, histologic and nuclear grade, extensive intraductal carcinoma component, lymphovascular invasion, and immunohistochemical profiles) and preoperative MRI features (tumor size, background parenchymal enhancement, internal enhancement, adjacent vessel sign, whole-breast vascularity, initial enhancement pattern, kinetic curve types, quantitative kinetic parameters, tumoral apparent diffusion coefficient [ADC], peritumoral maximal ADC, and peritumoral-tumoral ADC ratio). Multivariate logistic regressions were performed to determine independent variables associated with SLN metastasis, and the area under the receiver operating characteristic curve (AUC) was analyzed for those variables. 41 (13.3%) of the patients showed SLN metastasis. With MRI, tumor size (odds ratio [OR], 1.11; 95% confidence interval [CI], 1.06-1.17), heterogeneous (OR, 5.33; 95% CI, 1.71-16.58), and rim (OR, 15.54; 95% CI, 2.12-113.72) enhancement and peritumoral-tumoral ADC ratio (OR, 72.79; 95% CI, 7.15-740.82) were independently associated with SLN metastasis. Clinicopathologic variables independently associated with SLN metastasis included age (OR, 0.96; 95% CI, 0.92-0.99) and CD31 (OR, 2.90; 95% CI, 1.04-8.92). The area under the curve (AUC) of MRI features (0.80; 95% CI, 0.73-0.87) was significantly higher than for clinicopathologic variables (0.68; 95% CI, 0.60-0.77; P = 0.048) and was barely below statistical significance for combined MRI features with clinicopathologic variables (0.84; 95% CI 0.78-0.90, P = 0.057). Preoperative internal enhancement on DCE-MRI and peritumoral-tumoral ADC ratio on DWI might be useful for predicting SLN metastasis in patients with invasive breast cancer. 3 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2020;51:615-626.