Neoadjuvant Chemotherapy In Breast Cancer Research Articles

GSDME-mediated pyroptosis promotes anti-tumor immunity of neoadjuvant chemotherapy in breast cancer

Paclitaxel and anthracycline-based chemotherapy is one of the standard treatment options for breast cancer. However, only about 6–30% of breast cancer patients achieved a pathological complete response (pCR), and the mechanism responsible for the difference is still unclear. In this study, random forest algorithm was used to screen feature genes, and artificial neural network (ANN) algorithm was used to construct an ANN model for predicting the efficacy of neoadjuvant chemotherapy for breast cancer. Furthermore, digital pathology, cytology, and molecular biology experiments were used to verify the relationship between the efficacy of neoadjuvant chemotherapy and immune ecology. It was found that paclitaxel and doxorubicin, an anthracycline, could induce typical pyroptosis and bubbling in breast cancer cells, accompanied by gasdermin E (GSDME) cleavage. Paclitaxel with LDH release and Annexin V/PI doubule positive cell populations, and accompanied by the increased release of damage-associated molecular patterns, HMGB1 and ATP. Cell coculture experiments also demonstrated enhanced phagocytosis of macrophages and increased the levels of IFN-γ and IL-2 secretion after paclitaxel treatment. Mechanistically, GSDME may mediate paclitaxel and doxorubicin-induced pyroptosis in breast cancer cells through the caspase-9/caspase-3 pathway, activate anti-tumor immunity, and promote the efficacy of paclitaxel and anthracycline-based neoadjuvant chemotherapy. This study has practical guiding significance for the precision treatment of breast cancer, and can also provide ideas for understanding molecular mechanisms related to the chemotherapy sensitivity.

Breast Cancer Patient’s Outcomes after Neoadjuvant Chemotherapy and Surgery at 5 and 10 Years for Stage II–III Disease

Introduction: Neoadjuvant chemotherapy in breast cancer offers the possibility to facilitate breast and axillary surgery; it is a test of chemosensibility in vivo with significant prognostic value and may be used to tailor adjuvant treatment according to the response. Material and Methods: A retrospective single-institution cohort of 482 stage II and III breast cancer patients treated with neoadjuvant chemotherapy based on anthracycline and taxans, plus antiHEr2 in Her2-positive cases, was studied. Survival was calculated at 5 and 10 years. Kaplan–Meier curves with a log-rank test were calculated for differences according to age, BRCA status, menopausal status, TNM, pathological and molecular surrogate subtype, 20% TIL cut-off, surgical procedure, response to chemotherapy and the presence of vascular invasion. Results: The pCR rate was 25.3% and was greater in HER2 (51.3%) and TNBC (31.7%) and in BRCA carriers (41.9%). The factors independently related to patient survival were pathology and molecular surrogate subtype, type of surgery, response to NACT and vascular invasion. BRCA status was a protective prognostic factor without reaching statistical significance, with an HR 0.5 (95%CI 0.1–1.4). Mastectomy presented a double risk of distant recurrence compared to breast-conservative surgery (BCS), supporting BCS as a safe option after NACT. After a mean follow-up of 126 (SD 43) months, luminal tumors presented a substantial difference in survival rates calculated at 5 or 10 years (81.2% compared to 74.7%), whereas that for TNBC was 75.3 and 73.5, respectively. The greatest difference was seen according to the response in patients with pCR, who exhibited a 10 years DDFS of 95.5% vs. 72.4% for those patients without pCR, p < 0001. This difference was especially meaningful in TNBC: the 10 years DDFS according to an RCB of 0 to 3 was 100%, 80.6%, 69% and 49.2%, respectively, p < 0001. Patients with a particularly poor prognosis were those with lobular carcinomas, with a 10 years DDFS of 42.9% vs. 79.7% for ductal carcinomas, p = 0.001, and patients with vascular invasion at the surgical specimen, with a 10 years DDFS of 59.2% vs. 83.6% for those patients without vascular invasion, p < 0.001. Remarkably, BRCA carriers presented a longer survival, with an estimated 10 years DDFS of 89.6% vs. 77.2% for non-carriers, p = 0.054. Conclusions: Long-term outcomes after neoadjuvant chemotherapy can help patients and clinicians make well-informed decisions.

Time to surgery after neoadjuvant chemotherapy in breast cancer and its impact on survival in a middle-income country.

e12640 Background: The time to surgery after neoadjuvant chemotherapy (NACT) in breast cancer and its impact on survival has not been sufficiently evaluated in low- or middle-income countries. The objective of this study was to analyze the impact on overall survival in a cancer hospital in Guayaquil, Ecuador. Methods: This is a retrospective study carried out at the SOLCA Guayaquil Hospital in Ecuador from January 2009 to December 2011. The inclusion criteria were women ≥18 years old, diagnosed with invasive breast cancer in stages II and III, who were treated with NACT followed by surgery. The data were collected from clinical records; those with incomplete data were excluded, and the variables age, stage, lymphovascular invasion (LVI), and pathological response were included. Survival was grouped into <8 and ≥8 weeks for the comparative analysis. Survival time was calculated from diagnosis by biopsy until death; A p-value of ˂0.05 was taken as significant; The Kaplan-Meier estimate was used for overall survival, then the groups were compared by Log Rank, and the influence of the covariates was estimated in the Cox regression model. The data were analyzed in an SPSS v29 statistical program. Results: 200 patients were identified, 195 of whom had all the information for the analysis. The median time between the end of NACT and surgery was 7.57 weeks (range, 2.43-29.14 weeks). In the < 8 and ≥ 8 weeks group, there were 111 and 84 patients, respectively. The clinical characteristics are described in the Table. The median overall survival in the entire cohort was 8.32 years (CI: 6.68-9.96), and for the < 8 and ≥ 8 weeks groups, it was 10.0 and 6.56 years, respectively, with a Log-Rank of 0.031. The follow-up (median) of the entire cohort was 7.54 years (range 0.63 – 10.99 years). The multivariate Cox regression showed that LVI, HR: 2.35 p<0.001; clinical stage III (II vs III), HR: 2.47 p<0.001; residual disease (pathological complete response vs residual disease), HR: 2.70 p=0.012; age ≤ 50 years (≤ 50 years vs > 50 years), HR: 1.69 p=0.011; were factors that statistically contributed to worse survival, however, the time between the end of NACT and surgery < 8 and ≥ 8 weeks (p = 0.07) had no statistical impact on survival. Nonetheless, a numerical trend towards better survival was noted in the < 8 week group. Conclusions: The delay in time to surgery after NACT had a negative trend in survival, although it was not statistically significant, which may be due to the small sample size. [Table: see text]

Trends and outcomes in patients receiving neoadjuvant chemotherapy for breast cancer in Ontario: A population-based study.

e12664 Background: Modern neoadjuvant chemotherapy (NAC) regimens in breast cancer offer higher rates of pathologic complete response, an ability to guide further adjuvant treatment, and may de-escalate surgery. However, the utilization of NAC has been heterogeneous in Ontario. This study aimed to describe trends in NAC use in Ontario, report survival outcomes, and explore factors associated with overall survival in these patients. Methods: This was a population-based cohort study using linked health administrative data in Ontario, Canada. From the Ontario Cancer Registry, we identified women ≥18 years who underwent neoadjuvant chemotherapy followed by surgery for operable (cT1N1, cT2-3N0, or cT2-3N1) breast cancer between 2012 and 2020. Patients were divided by receptor subtype (triple negative breast cancer [TNBC], ER+/HER2-, ER+/HER2+, ER-/HER2+) and characteristics were compared using standardized mean differences (SMDs). Five-year overall survival (OS) and breast cancer-specific survival (BCSS) were determined and reported for each subtype. Associations with OS and BCSS were calculated for patient and disease characteristics using univariate and multivariable Cox proportional hazards models and Fine and Gray models, respectively. Results: 3,804 women underwent NAC for cT1N1, cT2-3N0, or cT2-3N1 breast cancer in Ontario between 2012 and 2020. The largest contributing subtype was ER+/HER2- patients (39.3%) followed by those with HER2+ disease (ER-/HER2+ 13.8%, ER+/HER2+ 23.4%), and TNBC (23.5%). The median age was 50 years (IQR 42-59 years). Most patients were clinically node-positive (2,736; 71.9%), and underwent mastectomy (2,397; 63.0%). There was a significant increase in the number of patients receiving NAC in Ontario, from 217 in 2012 to 667 in 2019 ( p<0.001), with a greater increase among patients with TNBC or HER2+ disease. Compared to those with ER+/HER2- disease, TNBC patients were treated for smaller tumours (28.6% T3 vs. 39.8%; SMD = 0.24), and were more likely to be node-negative (39.1% N0 vs. 22.1%; SMD = 0.38). Similar trends for nodal status were found for patients with ER-/HER2+ (26.7% N0) and ER+/HER2+ cancer (27.9% N0). 5-year OS for the entire cohort was 88.1% (95% CI 87.1 – 89.2%). Survival was highest for ER+/HER2+ patients (94.2%, 95% CI 92.6 – 95.8%) and lowest for TNBC patients (80.1%, 95% CI 77.5 – 82.8%). Similar patterns were seen for BCSS. Factors associated with OS in a multivariable model included older age (increase in 5 years HR 1.1, 95% CI 1.07 – 1.14), N1 status (HR 1.99, 95% CI 1.61 – 2.47), larger tumour size (T3 HR 1.83, 95% CI 1.34 – 2.5), mastectomy (HR 1.45, 95% CI 1.2 – 1.75), and TNBC (versus ER+/HER2- HR 1.9, 95% CI 1.56 – 2.32). Conclusions: The use of NAC has increased in Ontario, particularly among TNBC and HER2+ patients. Women with TNBC have worse outcomes compared to those with ER+/HER2- disease, despite being treated for less advanced disease.

Surgical decision-making after neoadjuvant chemotherapy for breast cancer.

e23282 Background: Following neoadjuvant chemotherapy (NAC), a significant subset of breast cancer patients become candidates for breast conserving surgery (BCS) after tumor downstaging. Studies have shown there is no survival advantage between BCS and mastectomy after NAC and that patient prognosis is largely predicted by the pathologic response to treatment. While the literature highlights many aspects of surgical decision-making in breast cancer, there is little analysis of patient choice after NAC. The goal of this study is to investigate clinical and demographic factors that may associate with patients’ surgical decision-making after receiving NAC as well as related outcomes. Methods: A retrospective chart review was conducted on breast cancer patients at our institution who became BCS candidates after receiving NAC from 1/1/2010 to 9/30/2020. Patient demographics, clinical characteristics, choice of mastectomy versus BCS, and outcomes were compared. Exclusion criteria included inflammatory, recurrent, and bilateral breast cancers, and patients with genetic predisposition. T-tests and chi-squared tests of association were used for continuous and categorical variables respectively. Survival outcomes were reported using the log-rank test. The p-value threshold for significance was p < 0.05. Statistical analysis was performed using R software version 4.2.3. Results: In this analysis, 244 patients met study criteria, of which 181 (74.2%) patients chose BCS and 63 (25.8%) patients elected mastectomy. Patients who chose mastectomy were younger at time of diagnosis than those who chose BCS: median age 48 years in mastectomy group versus 53 years in BCS group (p = 0.003). Regarding physical exam findings, while palpability of the primary breast tumor was not associated with choice of surgery (p = 0.271), presence of axillary lymphadenopathy was associated with a higher likelihood of choosing mastectomy (44.4% in mastectomy subgroup versus 29.3% in BCS subgroup, p = 0.041). Patient race, pre-treatment clinical stage, and doxorubicin-based chemotherapy were not associated with patients’ decisions for type of surgery. With respect to outcomes, follow-up time was similar between both groups with overall median of 5 years, and there was no significant difference in local or distant recurrence, and overall mortality (log-rank p = 0.3). Conclusions: The majority of breast cancer patients elect BCS after downstaging from NAC. Factors that are associated with choosing mastectomy include younger age at diagnosis and pre-treatment palpable axillary lymphadenopathy, which may be perceived as more advanced stage, despite no difference in stage between both groups. Regardless of surgical choice, both recurrence and mortality rates did not significantly differ between patients who chose BCS versus mastectomy, which is consistent with the literature.

Personalized circulating tumor DNA for minimal residual disease and dynamic assessment in patients undergoing neoadjuvant chemotherapy for breast cancer: Preliminary analysis from MSK-LINC.

Personalized circulating tumor DNA for minimal residual disease and dynamic assessment in patients undergoing neoadjuvant chemotherapy for breast cancer: Preliminary analysis from MSK-LINC.

Ten-year outcomes of targeted axillary surgery after neoadjuvant chemotherapy in breast cancer.

600 Background: When pathological complete response (pCR) is achieved in node-positive breast cancer after neoadjuvant chemotherapy (NAC), identifying traces of the previous lesion becomes challenging which makes accurate surgery difficult. We conducted targeted axillary surgery (TAS) in node-positive breast cancer after NAC, which involves accurately targeting the lymph nodes where metastasis occurred and performing surgery using a less extensive method. The 10-year outcomes were compared with those of patients who underwent conventional axillary lymph node dissection (ALND). Methods: We conducted a retrospective analysis of 235 patients with cT1-3N1-2 breast cancer who received NAC from 2012 to 2017. In this cohort, 78 patients underwent TAS only, and 157 underwent conventional ALND, including 31 patients who initially received TAS followed by additional ALND. Oncologic results, including locoregional recurrence-free survival (LRFS), distant metastasis-free survival (DMFS), and overall survival (OS), were assessed over a 10-year follow-up period. Survival outcomes for all patients and each subtype were analyzed using Kaplan-Meier survival methods. Results: The TAS group had significantly more postmenopausal patients (p=0.022), and the most common type of breast cancer was invasive ductal carcinoma [TAS: 75 (96.2%); ALND: 157 (100.0%)]. There was no statistical difference in the T stage and the number of lymph nodes suspected of metastasis at diagnosis (p=0.062, 0.985). Mastectomy was performed in 60.3% of patients in the TAS group and 93.0% in the ALND group (p<0.001), and 68 (87.2%) of the TAS group and 41 (26.1%) of the ALND group received additional axillary radiotherapy (p=0.019). There was no significant difference in oncologic outcomes between the TAS and ALND groups in all patients (LRFS, p=0.673; DMFS, p=0.729; OS, p=0.396) and based on subtypes, including hormone receptor (HR)-positive, HER2-positive, and triple-negative breast cancer (TNBC). In the HR-positive breast cancer group, the TAS and ALND groups showed very similar trends (LRFS, p=0.954; DMFS, p=0.993; OS, p=0.617). In HER2-positive breast cancer, although not statistically significant, the survival outcomes were better in the TAS group than in the ALND group (LRFS, p=0.967; DMFS, p=0.999; OS, p=0.423). However, the OS in the TAS group for TNBC was lower than that in the ALND group, though not significantly (LRFS, p=0.411; DMFS, p=0.697; OS, p=0.210). Conclusions: This study demonstrates that TAS is comparable to ALND in terms of 10-year oncological outcomes across different types of node-positive breast cancer, suggesting its potential as a viable alternative. However, further research focusing on patient quality of life and postoperative complications is essential to establish TAS as a superior surgical option to ALND.

Relationship between Tumor Infiltrating Lymphocytes and Neoadjuvant Chemoterapy Responsiveness: A Cross-Sectional Study on Breast Cancer Patients

Breast cancer is still a significant health problem in the world, with chemotherapy as an essential component in its management. Limited research on tumor- infiltrating lymphocytes (TIL) as a biomarker for the effectiveness of breast cancer treatment was conducted and is still contradictory. This study aims to investigate the relationship between TILs and the clinical response to neoadjuvant chemotherapy in breast cancer. The research used a cross-sectional study on eligible breast cancer patients in Wahidin Sudirohusodo Hospital in Makassar. TIL levels were grouped based on the histopathological examination results of breast tissue samples into three categories: low (0% to 10%), medium 15% to 50% and high (55% to 100%). Responsiveness was assessed based on changes in tumor size after neoadjuvant chemotherapy. The Chi-Square test is the primary analysis in this study. Results of 40 participants, the sample had a median age of 40 (27-73 years), mainly in the clinical stage III (40.0%), had moderate TIL concentration (47.5%), and was responsive to the neoadjuvant chemotherapy (87.5%). There was no significant association between TIL concentration and chemotherapy responsiveness (p > 0.05). However, in post-chemotherapy conditions, the median value of tumor size in the group with the high TIL category was significantly lower than in the low and medium TIL groups (p=0.034). There was no association between TIL levels and the clinical response to neoadjuvant chemotherapy in breast cancer patients. Further research is needed to confirm these findings.

Comprehensive analysis of plasma methylome reveals distinct patterns of methylation changes between responders and non-responders to neoadjuvant chemotherapy in breast cancer

The potential of cell-free DNA (cfDNA) methylation profiling in oncology is increasingly recognized for its ability to offer a comprehensive assessment of tumor biology. In this report, we explore the plasma methylome dynamics in patients with early breast cancer (BC) undergoing neoadjuvant chemotherapy (NACT) using an agnostic genome-wide approach with cell-free DNA immunoprecipitation and sequencing (cfMeDIP-seq). Our cohort comprised seven women with triple-positive BC, assessed for cfDNA methylation changes at multiple time points during their treatment course. Genome-wide analysis revealed distinctive patterns of differential methylation in patients achieving pathological complete response (pCR), with no significant epigenomic modifications in patients with residual disease (RD). Gene set enrichment analysis highlighted dynamic variations in functional pathways associated with therapy response, including metabolism, immune response, and response to xenobiotics, with a notable reversibility post-treatment. Principal component analysis of the differentially methylated regions demonstrated a clear distinction between pCR and RD patients, indicating the potential of cfMeDIP-seq for the non-invasive assessment of therapy response. Such findings suggest that cfMeDIP-seq could complement ctDNA offering broader insights into the global modifications induced by chemotherapy. Although future research is needed to validate and expand on our findings, we offer a proof-of-principle of the potential utility of cfMeDIP-seq in the personalized management of BC.

Predictive analysis of breast cancer response to neoadjuvant chemotherapy through plasma metabolomics.

Preoperative chemotherapy is a critical component of breast cancer management, yet its effectiveness is not uniform. Moreover, the adverse effects associated with chemotherapy necessitate the identification of a patient subgroup that would derive the maximum benefit from this treatment. This study aimed to establish a method for predicting the response to neoadjuvant chemotherapy in breast cancer patients utilizing a metabolomic approach. Plasma samples were obtained from 87 breast cancer patients undergoing neoadjuvant chemotherapy at our facility, collected both before the commencement of the treatment and before the second treatment cycle. Metabolite analysis was conducted using capillary electrophoresis-mass spectrometry (CE-MS) and liquid chromatography-mass spectrometry (LC-MS). We performed comparative profiling of metabolite concentrations by assessing the metabolite profiles of patients who achieved a pathological complete response (pCR) against those who did not, both in initial and subsequent treatment cycles. Significant variances were observed in the metabolite profiles between pCR and non-pCR cases, both at the onset of preoperative chemotherapy and before the second cycle. Noteworthy distinctions were also evident between the metabolite profiles from the initial and the second neoadjuvant chemotherapy courses. Furthermore, metabolite profiles exhibited variations associated with intrinsic subtypes at all assessed time points. The application of plasma metabolomics, utilizing CE-MS and LC-MS, may serve as a tool for predicting the efficacy of neoadjuvant chemotherapy in breast cancer in the future after all necessary validations have been completed.

Longitudinal ultrasound-based AI model predicts axillary lymph node response to neoadjuvant chemotherapy in breast cancer: a multicenter study.

Developing a deep learning radiomics model from longitudinal breast ultrasound and sonographer's axillary ultrasound diagnosis for predicting axillary lymph node (ALN) response to neoadjuvant chemotherapy (NAC) in breast cancer. Breast cancer patients undergoing NAC followed by surgery were recruited from three centers between November 2016 and December 2022. We collected ultrasound images for extracting tumor-derived radiomics and deep learning features, selecting quantitative features through various methods. Two machine learning models based on random forest were developed using pre-NAC and post-NAC features. A support vector machine integrated these data into a fusion model, evaluated via the area under the curve (AUC), decision curve analysis, and calibration curves. We compared the fusion model's performance against sonographer's diagnosis from pre-NAC and post-NAC axillary ultrasonography, referencing histological outcomes from sentinel lymph node biopsy or axillary lymph node dissection. In the validation cohort, the fusion model outperformed both pre-NAC (AUC: 0.899 vs. 0.786, p < 0.001) and post-NAC models (AUC: 0.899 vs. 0.853, p = 0.014), as well as the sonographer's diagnosis of ALN status on pre-NAC and post-NAC axillary ultrasonography (AUC: 0.899 vs. 0.719, p < 0.001). Decision curve analysis revealed patient benefits from the fusion model across threshold probabilities from 0.02 to 0.98. The model also enhanced sonographer's diagnostic ability, increasing accuracy from 71.9% to 79.2%. The deep learning radiomics model accurately predicted the ALN response to NAC in breast cancer. Furthermore, the model will assist sonographers to improve their diagnostic ability on ALN status before surgery. Our AI model based on pre- and post-neoadjuvant chemotherapy ultrasound can accurately predict axillary lymph node metastasis and assist sonographer's axillary diagnosis. Axillary lymph node metastasis status affects the choice of surgical treatment, and currently relies on subjective ultrasound. Our AI model outperformed sonographer's visual diagnosis on axillary ultrasound. Our deep learning radiomics model can improve sonographers' diagnosis and might assist in surgical decision-making.

Factors Associated With Additional Axillary Disease in Patients With Positive Sentinel Lymph Nodes After Neoadjuvant Chemotherapy for Breast Cancer.

Background: In previous studies, breast cancer patients with positive sentinel lymph node(s) (SLN) after neoadjuvant chemotherapy (NAC) frequently had additional nonSLN involvement. Per guidelines, residual SLN disease warrants completion axillary lymph node dissection (cALND), which has increased morbidity. Given recent improvements in NAC, we hypothesized that nonSLN positivity may be lower than previously reported for certain subgroups.Methods: We retrospectively reviewed breast cancer patients who received NAC and had positive lymph nodes on SLN biopsy or targeted axillary dissection and underwent cALND at one institution in 1/2018-8/2023. Associations between nonSLN positivity and clinicopathologic factors were assessed with Fisher's exact test and multivariable logistic regression.Results: There were 122 female patients. Median age was 48years. Initially, 15 patients (12.3%) were cN0 and 107 patients (87.7%) were cN1. Largest SLN deposit was macrometastasis in 96 patients (78.7%), micrometastasis in 23 patients (18.9%), and isolated tumor cells in 3 patients (2.5%). Overall, 53 patients (43.4%) had nonSLN involvement. NonSLN positivity was higher in patients with cN1, ER+ HER2-, ypT2-3, SLN macrometastasis, and multiple positive SLN. On multivariable analysis, cN1 and ER+ HER2- remained associated with nonSLN positivity.Discussion: Among patients with positive SLN after NAC, clinically node positive and ER+ HER2- patients were more likely to have nonSLN involvement. Our findings support guidelines to consider omitting cALND in clinically node negative patients. With improving NAC, optimal axillary sampling, and radiation, omitting cALND may be safe in some clinically node positive triple negative or HER2+ patients with low volume residual disease, but further research is needed.

Predictive value of pretreatment circulating inflammatory response markers in the neoadjuvant treatment of breast cancer: meta-analysis.

Systemic inflammatory response markers have been found to have a prognostic role in several cancers, but their value in predicting the response to neoadjuvant chemotherapy in breast cancer is uncertain. A systematic review and meta-analysis of the literature was carried out to investigate this. A systematic search of electronic databases was conducted to identify studies that explored the predictive value of circulating systemic inflammatory response markers in patients with breast cancer before commencing neoadjuvant therapy. A meta-analysis was undertaken for each inflammatory marker where three or more studies reported pCR rates in relation to the inflammatory marker. Outcome data are reported as ORs and 95% confidence intervals. A total of 49 studies were included, of which 42 were suitable for meta-analysis. A lower pretreatment neutrophil-to-lymphocyte ratio was associated with an increased pCR rate (pooled OR 1.66 (95% c.i. 1.32 to 2.09); P < 0.001). A lower white cell count (OR 1.96 (95% c.i. 1.29 to 2.97); P = 0.002) and a lower monocyte count (OR 3.20 (95% c.i. 1.71 to 5.97); P < 0.001) were also associated with a pCR. A higher lymphocyte count was associated with an increased pCR rate (OR 0.44 (95% c.i. 0.30 to 0.64); P < 0.001). The present study found the pretreatment neutrophil-to-lymphocyte ratio, white cell count, lymphocyte count, and monocyte count of value in the prediction of a pCR in the neoadjuvant treatment of breast cancer. Further research is required to determine their value in specific breast cancer subtypes and to establish optimal cut-off values, before their adoption in clinical practice.

Abstract PO2-23-04: Magnetic Seeds, used to Locate the Metastatic Axillary Lymph Node placed before Neoadjuvant Chemotherapy for Breast Cancer Treatment, do not interfere the pre-surgical MRI Breast response assessment

Abstract Background: Axillary management in clinically node-positive patients who converted to ycN0 after neoadjuvant chemotherapy (NAC) for breast cancer (BC) remains under research with the aim of de-escalation of axillary lymph node dissection (ALND). A magnetic seed is one of the several positive lymph nodes marking techniques used in targeted axillary dissection (TAD) for patients with cN1 breast cancer undergoing neoadjuvant systemic therapy. It has been criticized for its potential masking effect due to the artefact it produces in the MRI sequences used to assess a proper breast response. This study evaluates if the magnetic seeds placed before NAC for guided TAD have influenced in the breast MRI response assessments. Methods: From October 2021 to June 2023, patients with cT0-4 cN1 breast cancer who were candidates for primary systemic treatment were prospectively recruited. Once a breast lesion and axillary node positivity were confirmed, a based hydrogel marker and a magnetic seed, respectively, were placed prior NAC. Once systemic treatment was completed, imaging techniques were used to assess the response, with MRI being the imaging technique of choice to assess breast response and axillary ultrasound the imaging technique of choice to assess axillary response. Surgical pathological confirmation of response in the axilla was by TAD, including sentinel lymph node and magnetic clipped node resection. Results: A total of 43 patients were included and their characteristics are shown in Table 1. In 16 patients (37%) the tumour was located in the upper outer quadrant (UOQ). In this group, the susceptibility artefact produced by the magnetic seed in the MRI created a black hole obscuring the axilla with a mean diameter of 69 mm (range: 57-76 mm). In no case did the halo interfere with the correct MRI visualisation of the breast marker. By MRI, the mean distance of the artifact halo from the breast marker or residual breast lesion was 40 mm (range: 13-79 mm). Overall, complete radiological response (ycCR) was reported in 20 patients (46%), breast only in 21 (49%) and axilla only in 38 (88%) patients. In 5 patients, preoperative axillary ultrasound revealed residual axillary disease, confirmed by FNA, lead to direct ALND. In the remaining 38 patients the axillary TAD assessment was completed. In all cases, the magnetic clipped node was successfully surgically removed. Pathological complete response (pCR) was confirmed in 9 (21%), breast only in 11 (26%) and axilla only in 13 (30%) patients. MRI diagnostic performance in detecting residual breast disease after NAC was not altered by the magnetic clipped node artifact when comparing the tumour location in the UOQ to the other quadrants (AUC 0.764 vs. 0.702; p=0.698). Conclusions: Surgical axillary staging remains the most reliable method for assessing the axillary response after NAC. Target axillary dissection guided by magnetic seed placed before NAC is an effective and accurate technique. The artifact generated in the MRI does not interfere with the pre-surgical breast response assessment after neoadjuvant systemic treatment. Table 1: Patients and tumor characteristics Citation Format: Martin Espinosa-Bravo, Joaquin Rivero Deniz, Clara Morales Comas, Javier de la Torre Fernandez de Vega, Irene Vives Rosello, Enrica Esposito, Vicente Peg Camara, María De Les Neus Rus Calafell, Ignacio Miranda Gomez, Christian Siso Raber. Magnetic Seeds, used to Locate the Metastatic Axillary Lymph Node placed before Neoadjuvant Chemotherapy for Breast Cancer Treatment, do not interfere the pre-surgical MRI Breast response assessment [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 PO2-23-04.

Abstract PO1-09-11: Racial Differences in Pathologic Complete Response Rate and Overall Survival Following Neoadjuvant Chemotherapy for Breast Cancer

Abstract Background: Neoadjuvant chemotherapy (NAC) is increasingly used in the treatment of breast cancer and has been utilized in multiple clinical trials assessing the efficacy of novel therapies. Pathologic complete response (pCR) following NAC is associated with improved survival outcomes in breast cancer and pCR is a commonly used endpoint in clinical trials. Despite improvements in breast cancer survival using modern treatment regimens, Black women continue to experience worse survival outcomes as compared to White women. The objective of this study was to evaluate the association between race and clinical outcomes, specifically pCR rate, recurrence free survival and overall survival, in patients undergoing neoadjuvant chemotherapy at our institution. Methods: We conducted a retrospective review of patients who completed at least 75% of the recommended cycles of neoadjuvant chemotherapy for breast cancer between 2010 and 2016 and underwent surgery. Receptor subtypes were defined as HR+/HER2-negative, HER2+ or triple-negative. The association between race and pCR, defined as ypT0/ypTis ypN0, and survival endpoints of overall survival and recurrence free survival were analyzed using multivariable logistic regression and Cox proportional hazard models. Results: A total of 532 women met the inclusion criteria, 323 (60.7%) were White, 188 (35.3%) were Black and 21 (3.9%) were other/unknown. Median follow-up was 65 months. The receptor subgroups consisted of 195 (36.7%) HR+/HER2-negative cancers, 193 (36.3%) HER2+ cancers and 144 (27.1%) triple-negative cancers. No significant association between race and receptor subtype (p=0.55) or pre-treatment clinical stage (p=0.96) was observed. The overall observed pCR rate was 19% for Black patients and 27% for White patients, demonstrating a significantly different pCR rate by race in multivariate analysis (odds ratio of pCR White vs Black of 1.75; p=0.02). The largest discrepancy in pCR rate between White and Black patients was within subjects with triple-negative disease (pCR rate 44% White patients vs 27% Black patients, p=0.03). There was no association between recurrence free survival and race in univariate analysis (p=0.15). A significant difference in overall survival by race was observed using multivariable Cox proportions hazard model (hazard ratio Black vs White 1.77; p=0.03). Conclusions: In this retrospective analysis of patients receiving neoadjuvant chemotherapy, Black patients experienced a significantly lower pCR rate compared to White patients, with the biggest gap identified within triple-negative breast cancers. During the study period, Black patients also experienced a lower overall survival rate compared to White patients. Differences in the ability to achieve a pCR may be a contributing factor to the worse survival outcomes of Black patients. Citation Format: Chad Livasy, Erin Donahue, Brittany Neelands, Lejla Hadzikadic-Gusic, Terry Sarantou, Mckenzie Needham, Alicia Patrick, Arielle Heeke, Antoinette Tan, Richard White. Racial Differences in Pathologic Complete Response Rate and Overall Survival Following Neoadjuvant Chemotherapy for 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 PO1-09-11.

Abstract PO1-19-06: Physical exercise during neoadjuvant chemotherapy for breast cancer as a mean to increase pathological complete response rates: the randomized Neo-ACT trial

Abstract Introduction In early breast cancer, neoadjuvant chemotherapy (NACT) is increasingly used. The proof of efficacy is pathologically complete response (pCR), i.e. the absence of invasive tumour in breast and lymph nodes at surgery. Today, pCR is a common endpoint in pharmaceutical trials since it is significantly associated with survival especially in triple-negative and HER2-positive subtypes. Apart from the mitigation of treatment-related toxicity and symptoms, physical exercise mediates anti-tumoral systemic effects associated with tumour regression in preclinical and clinical models. The aim of Neo-ACT is to test the hypothesis that physical exercise can improve pCR rates in breast cancer patients receiving NACT. Method The Neo-ACT trial is an international prospective clinical trial, randomising T1-3N0-2 breast cancer patients planned for NACT to either a home-based physical exercise intervention supported by a mobile application or routine care. The primary endpoint is pCR; secondary endpoints are patient-reported quality of life, toxicity-related outcomes, and oncological outcomes such as Residual Cancer Burden, objective radiological tumour response, as well as overall, breast cancer-specific and disease-free survival at 2, 5 and 10 years. The intervention consists of a combination of high-intensity interval and resistance training of progressing intensity, and includes two weekly 60-min exercise sessions plus at least 150 min of moderate to vigorous physical activity per week. The Neo-ACT has been registered at clinicaltrials.gov on January 11, 2022 (NCT05184582). Statistical methods Patients will be randomized in a 1:1 fashion. It is anticipated that the rate of the primary endpoint pCR will be approximately 30% in the control arm (all subtypes). We aim to increase the rate of pCR in the experimental arm to 40%, i.e. a 10 percentage points increase, which is regarded clinically relevant since it would translate into improved disease-related outcomes. With a power of 80% and an alpha of 5%, a total of 712 patients have to be included; 356 in each arm. Accounting for a drop-out of 10%, we aim to include 790 patients. Stratification at the moment of computerized randomization is based on site of treatment (hospital) and biological tumour subtype (ER+HER2-, ER+HER2+, ER-HER2+, ER-HER2-). All outcomes will primarily be analysed using an intention-to-treat approach, i.e. all study subjects will belong to the treatment group (exercise intervention or control) they were assigned to, disregarding compliance. As sensitivity analysis, all outcomes will also be analysed using a per-protocol approach, meaning that participants in the intervention group who comply with less than 65% of the prescribed physical exercise program, and participants who complete less than 40% of the planned neoadjuvant systemic therapy (around two 3-weekly courses) will be excluded from analysis. Present accrual The Neo-ACT trial has started enrolment at the first site in December 2022 and since then initiated a further five Swedish and one Finnish site. Until June 15, 2023, 26 participants had been randomized in the trial. A feasibility questionnaire is distributed via the EUBREAST network which officially supports this trial and has added the designation EUBREAST12-R. Further participating sites can be accommodated depending on volume, competing trials and language requirements for the mobile application. Contact: jana.de-boniface@ki.se Citation Format: Jana de Boniface, Cecilia Haddad Ringborg, Renske Altena, Yvonne Wengström. Physical exercise during neoadjuvant chemotherapy for breast cancer as a mean to increase pathological complete response rates: the randomized Neo-ACT 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 PO1-19-06.

Abstract PO3-23-03: Radar reflectors for marking of target lymph nodes in patients receiving neoadjuvant chemotherapy for breast cancer – a subgroup analysis of the prospective AXSANA (EUBREAST-03) trial

Abstract Background: Surgical staging procedures of the axilla in breast cancer patients converting from a clinically positive (cN+) to a clinically negative (ycN0) lymph node status during neoadjuvant chemotherapy (NACT) vary across countries and within individual countries. The international prospective AXSANA (EUBREAST-03) study aims at comparatively evaluating long-term outcomes of different staging procedures such as axillary lymph node dissection (ALND), sentinel lymph node biopsy (SLNB), target lymph node biopsy (TLNB) and targeted axillary dissection (TAD). The comparison of marking techniques for the target lymph node (TLN) is a secondary endpoint. In this subgroup analysis, we report on the largest yet prospective cohort of patients receiving a radar reflector for marking of the TLN prior to NACT. Methods: The AXSANA study is an international prospective cohort study including cN+ patients converting to ycN0 status and treated with different axillary staging techniques according to the standard at their treating institution. The study was initiated by the EUBREAST network and started enrollment in August 2020. Eligible patients have cT1-4c tumors, initially present with axillary lymph node metastasis and receive neoadjuvant chemotherapy. Patients converting to ycN0 status are followed up for 5 years irrespectively of the ypN status. In the present subgroup analysis, only patients with a TLN marked by a radar reflector were included. We prospectively examined the retrieval rate of radar reflectors and the identification rate of the TLN (defined as unequivocal removal of the lymph node, i.e., the presence of lymphatic tissue in the TLN specimen and/or pathological confirmation of post-NACT changes typical for metastatic lymph nodes responding to treatment). Results: A TLN was marked using a radar reflector in 74 patients prior to NACT. The median age was 52 years (range: 32-77). The most common subtype was no special type in 68 (92%) patients and invasive lobular cancer in 7 (7%) patients. Most patients (n = 44, 59%) had one suspicious node at time of diagnosis, followed by two (n = 15, 20%), three (n = 10, 14%) or ≥ four suspicious nodes (n = 5, 5%). Only one TLN was marked in 73 (99%) patients and two nodes were marked in one patient (1%). Fifteen patients (20%) had a MRI between marker placement and surgery. In 4 out of 15 cases (27%), MRI artifacts were described. However, the assessment of MRI was limited due to artifacts only in one out of these four patients (25%). Out of the 74 patients with radar reflector marked TLN, 45 (61%) had undergone final surgery at the time of analysis and 29 (39%) are still under NACT. 36 out of 45 patients (80%) who received final surgery converted to ycN0. Most patients had undergone a TAD (n = 41, 91%), followed by TLNB in 7% (n = 3) and upfront ALND in 2% of cases (n = 1). All radar reflectors were successfully removed. In 44 out of 45 patients (98%) the TLN was unequivocally identified and removed. In one patient the tissue specimen containing radar reflector consisted of fat tissue and no lymphatic tissue was identifiable, so it remains unclear whether the TLN was excised, or the reflector might have dislocated. 29 patients (65%) had converted to ypN0 status. Conclusion: To the best of our knowledge this is the largest prospective series of patients receiving a radar reflector for the marking of TLN prior to NACT for breast cancer. The removal rate of the marker and the detection rate of the target node were very high. Our data demonstrate that radar reflectors are a reliable tool for marking of target lymph nodes before neoadjuvant treatment. Citation Format: Maggie Banys-Paluchowski, Steffi Hartmann, Jana de Boniface, Oreste Davide Gentilini, Timo Basali, Elmar Stickeler, Michael Untch, Franziska Ruf, Sarah Fröhlich, Marc Thill, Michael P. Lux, Florentia Peintinger, Guldeniz Karadeniz Cakmak, Isabel Rubio, Michalis Kontos, Rosa Di Micco, Dawid Murawa, Ellen Schlichting, Bilge Aktas Sezen, Achim Rody, Dagmar Langanke, Nana Bündgen, Jose Ignacio Sanchez-Mendez, Renu Buss-Steidle, Christine Mau, Nana Buchmann, Sabine Riemer, Marit Helene Hansen, Nina Ditsch, Thorsten Kühn. Radar reflectors for marking of target lymph nodes in patients receiving neoadjuvant chemotherapy for breast cancer – a subgroup analysis of the prospective AXSANA (EUBREAST-03) 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 PO3-23-03.

Abstract PO5-01-04: HER2 Amplification Level and Focal/Broad Region Size as Predictors of Treatment Response in Neoadjuvant Chemotherapy and Anti-HER2 Therapy for HER2-Positive Breast Cancer

Abstract Background: Neoadjuvant chemotherapy combined with anti-HER2 therapy has become the standard treatment approach for HER2-positive breast cancer. However, not all HER2-positive patients can achieve pathological complete response after neoadjuvant therapy. This raises the question of which subset of HER2+ patients derive the greatest benefit from pre-operative HER2-targeted treatment. Therefore, this study aims to determine whether the level and amplification region size of HER2 amplification are associated with the efficacy of neoadjuvant chemotherapy combined with anti-HER2 therapy. Methods: A total of 523 breast cancer samples were collected from 2017 to 2018, among which 202 cases were HER2-positive patients. Among these, 55 HER2-positive patients received neoadjuvant chemotherapy combined with anti-HER2 targeted therapy. The amplification status of HER2 was assessed using immunohistochemistry/fluorescence in situ hybridization (IHC/FISH) and next-generation sequencing (NGS). The HER2/CEP17 ratio, determined by FISH, was used to represent the amplification level of HER2. The size of the amplification region was calculated using NGS and neighboring genes located in chr17q. Amplification regions smaller than 1 Mb were classified as focal amplification, while those larger than 1 Mb were classified as broad amplification. Results: We compared the HER2/ERBB2 status of 523 breast cancer patients using different detection methods and found a high concordance between ERBB2 amplification detected by NGS and HER2-positivity detected by IHC and FISH, with a sensitivity of 96.0%, specificity of 97.8%, and overall concordance of 97.1%. Based on the HER2/CEP17 ratio determined by FISH, we observed that using a threshold of 6 for classification, the high amplification group had a significantly higher pCR rate compared to the low amplification group (86.7% vs. 41.7%; p=0.037, odds ratio [OR]=0.121, 95% confidence interval [CI]: 0.009-0.919). Moreover, the focal amplification group showed a higher pCR rate compared to the broad amplification group (65.9% vs. 30.8%, p=0.051, OR=0.237, 95% CI: 0.045-1.035). Additionally, within the low amplification group (HER2/CEP17 &amp;lt; 6), the pCR rate was 66.7% for focal amplification and 20% for broad amplification, suggesting that focal amplification of ERBB2 may further guide clinical benefit in the low HER2/CEP17 ratio group. Conclusion: This study demonstrates a high concordance between ERBB2 amplification determined by NGS and HER2-positivity determined by IHC/FISH. High HER2/CEP17 ratio and focal amplification of ERBB2 are associated with a higher pCR rate in neoadjuvant chemotherapy combined with anti-HER2 targeted therapy. Citation Format: Ning Liao, Guochun Zhang, Xinze Lv, Kai Li, Ting Hou, Zhou Zhang. HER2 Amplification Level and Focal/Broad Region Size as Predictors of Treatment Response in Neoadjuvant Chemotherapy and Anti-HER2 Therapy for HER2-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 PO5-01-04.

Abstract PO1-27-06: HER2 Amplification Level and Focal/Broad Region Size as Predictors of Treatment Response in Neoadjuvant Chemotherapy and Anti-HER2 Therapy for HER2-Positive Breast Cancer

Abstract Background: Neoadjuvant chemotherapy combined with anti-HER2 therapy has become the standard treatment approach for HER2-positive breast cancer. However, not all HER2-positive patients can achieve pathological complete response after neoadjuvant therapy. This raises the question of which subset of HER2+ patients derive the greatest benefit from pre-operative HER2-targeted treatment. Therefore, this study aims to determine whether the level and amplification region size of HER2 amplification are associated with the efficacy of neoadjuvant chemotherapy combined with anti-HER2 therapy. Methods: A total of 523 breast cancer samples were collected from 2017 to 2018, among which 202 cases were HER2-positive patients. Among these, 55 HER2-positive patients received neoadjuvant chemotherapy combined with anti-HER2 targeted therapy. The amplification status of HER2 was assessed using immunohistochemistry/fluorescence in situ hybridization (IHC/FISH) and next-generation sequencing (NGS). The HER2/CEP17 ratio, determined by FISH, was used to represent the amplification level of HER2. The size of the amplification region was calculated using NGS and neighboring genes located in chr17q. Amplification regions smaller than 1 Mb were classified as focal amplification, while those larger than 1 Mb were classified as broad amplification.&amp;gt; Results: We compared the HER2/ERBB2 status of 523 breast cancer patients using different detection methods and found a high concordance between ERBB2 amplification detected by NGS and HER2-positivity detected by IHC and FISH, with a sensitivity of 96.0%, specificity of 97.8%, and overall concordance of 97.1%. Based on the HER2/CEP17 ratio determined by FISH, we observed that using a threshold of 6 for classification, the high amplification group had a significantly higher pCR rate compared to the low amplification group (86.7% vs. 41.7%; p=0.037, odds ratio [OR]=0.121, 95% confidence interval [CI]: 0.009-0.919). Moreover, the focal amplification group showed a higher pCR rate compared to the broad amplification group (65.9% vs. 30.8%, p=0.051, OR=0.237, 95% CI: 0.045-1.035). Additionally, within the low amplification group (HER2/CEP17 &amp;lt; 6), the pCR rate was 66.7% for focal amplification and 20% for broad amplification, suggesting that focal amplification of ERBB2 may further guide clinical benefit in the low HER2/CEP17 ratio group. Conclusion: This study demonstrates a high concordance between ERBB2 amplification determined by NGS and HER2-positivity determined by IHC/FISH. High HER2/CEP17 ratio and focal amplification of ERBB2 are associated with a higher pCR rate in neoadjuvant chemotherapy combined with anti-HER2 targeted therapy. Citation Format: Ning Liao, Guochun Zhang, Xinze Lv, Kai Li, Ting Hou, Zhou Zhang. HER2 Amplification Level and Focal/Broad Region Size as Predictors of Treatment Response in Neoadjuvant Chemotherapy and Anti-HER2 Therapy for HER2-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 PO1-27-06.

Abstract PO3-12-08: Hypersensitivity reactions to paclitaxel and carboplatin in breast cancer: safety and effectiveness of desensitization

Abstract Introduction. Taxanes and platinums are first line treatment of breast cancer for early stages and metastatic disease and constitute the most commonly implicated chemotherapeutics in hypersensitivity reactions.1 Clinical manifestations range from mild skin reactions to anaphylaxis.2 Hypersensitivity reactions (HSR) to paclitaxel and carboplatin occur in a significant percentage of patients, with estimates of 30% and 40% respectively,3,4,5 leading to discontinuation of treatment.6 Using alternative drugs can be poorly tolerated or much less effective, entailing to high morbidity and mortality.7 Desensitization is the procedure performed to achieve a tolerance to the drug to which a HSR previously occurred, in order to maintain first-line treatment.8 The evaluation of the oncological response remains in the importance of assessing the shrinkage of the tumor and the time of progression of the disease.9 Objective: To describe the hypersensitivity reactions to paclitaxel and carboplatin, and the safety and effectiveness of desensitization protocols after anaphylaxis in patients with breast cancer. Materials and Methods: Original, retrospective, descriptive, and analytical study, approved by the Bioethics and Research Committee ON23-00016 code, included patients &amp;gt;18 years with breast cancer who developed a hypersensitivity reaction to first-line chemotherapy and performed a 3-bag-12-step desensitization according to the Brigham and Women's Hospital, Dana Farber Institute, Boston protocol. Results: Forty-five desensitization to paclitaxel or carboplatin were performed in 8 women with breast cancer, mean age 38.6 years. 6 patients developed HSR to paclitaxel, 83% of which were in the first application, and 2 patients developed HSR to carboplatin after several cycles. The most predominant symptom of HSR was cutaneous in 87% of the cases, and all patients presented cardiovascular HSR to paclitaxel. No patients developed HSR during desensitization. Currently, only 1 patient developed disease progression, while the rest presented a complete response to treatment. Discussion. HSR to paclitaxel appear in the 1-2 cycle,10 while to platinums after various exposures ( &amp;gt;6 cycles) similar to our study.3,4 The symptoms associated with paclitaxel are cardiovascular10,11 while urticaria is the most frequent in carboplatin.3,11 The desensitization protocol implemented did not develop HSR in any of the patients. Neoadjuvant chemotherapy in breast cancer has been shown to yield better disease-free interval results alongside improved pathological response.12 Conclusions. The program implemented in our hospital's chemotherapy desensitization clinic, replicating the model of the Dana-Farber Cancer Institute, Brigham, and Women's Hospital in Boston, has enabled cancer patients to continue with first-line treatment, thus improving their prognosis and quality of life, opening new areas of opportunity in the multidisciplinary management of these patients to improve overall survival. Characteristics of patients with hypersensitivity reactions HSR: hypersensitivity reactions ND: No data m: months yrs.: years Desensitization protocol to Paclitaxel IV (300 mg) IV: intravenous mg: milligram mL: milliliter h: hour Citation Format: Rosalaura V. Villarreal-González, Oscar Vidal-Gutiérrez, Javier A. Martínez-Moyano, Marianela Madrazo-Morales, Kathia S. Sáenz-Cantú, Patricia Rodríguez-Niño. Hypersensitivity reactions to paclitaxel and carboplatin in breast cancer: safety and effectiveness of desensitization [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 PO3-12-08.