Locally Advanced Breast Cancer Research Articles

Breast Conserving Surgery Post Neo-Adjuvant Chemotherapy for Locally Advanced Breast Carcinoma in a Developing Country: Is It Safe?

Breast conserving surgery (BCS) is the standard treatment for early breast cancer and has similar survival with mastectomy. The role of BCS in locally advanced breast cancer (LABC), post neoadjuvant chemotherapy (NACT), is controversial. Surgeons, especially in developing countries, fear higher margin involvement and local recurrence (LR) in BCS. The aim of this study was to determine the LR in BCS compared to mastectomy in LABC post NACT and to ascertain the percentage of involved surgical margins following both methods of surgery. This was a retrospective study of breast cancer patients seen in Universiti Kebangsaan Malaysia Medical Centre (UKMMC). All patients had NACT followed by either mastectomy or BCS. The patients with Her2 enriched carcinomas did not have access to targeted therapy (Trastuzumab or Pertuzumab). The patients with ill-defined tumours underwent ultrasound assessment in the surgical clinics. All had post-operative radiotherapy. All with ER or PR positive cancers were given Tamoxifen for a minimum of 5 years. This study demonstrated that BCS post NACT was safe to be performed in selected patients with LABC in a developing country.

Abstract PO3-05-13: A Multi-Institutional Review of Contralateral Axillary Metastases: Time for Reclassification as Local-Regional Event?

Abstract Background Current American Joint Committee on Cancer (AJCC) breast cancer staging considers contralateral axillary metastasis (CAM) stage IV disease (M1). Retrospective studies suggest that women with CAM have improved overall survival (OS) compared to those with distant metastasis (M1) and/or comparable OS to locally advanced breast cancer (LABC). These studies support consideration of curative intent treatment; however, they contain heterogeneous cohorts with highly variable treatment strategies. We sought to evaluate treatment and outcomes in a well-defined CAM cohort treated with contemporary systemic and locoregional therapy. Methods We performed a retrospective multi-institution cohort study to compare OS of patients with CAM matched 1:3 on age +/- 5 years to LABC (defined as cN2-3 and/or pN2-3), and to non-CAM M1. CAM patients classified as type 1) de novo CAM, synchronous with the contralateral primary, 2) metachronous isolated CAM in the setting of prior surgical and/or radiation treatment to primary index cancer, 3) synchronous with, or 4) metachronous after an in-breast or axillary nodal recurrence of the primary index cancer. The M1 cohort included de novo and recurrent metastasis with varied sites and number of metastasis. OS was defined as time from CAM diagnosis to death or last follow-up for CAM patients; time from primary diagnosis to death or last follow-up for LABC; and time from metastatic diagnosis to death or last follow-up for M1. Unadjusted OS was estimated with the Kaplan-Meier method, and Cox proportional hazards models were used to estimate the association of group with OS after adjustment for covariates Results We identified 57 CAM and 155 LABC from 8 institutions (2016-2022), and 632 M1 from a single institution. The median age was similar between groups (CAM=59 years, LABC=58, M1=57, p=0.44), and there were no statistically significant differences in hormone receptor status (p=0.25). There were more Non-Hispanic Black patients in the M1 cohort compared to CAM or LABC (p< 0.001). The majority of CAM cases were delayed metachronous from the index cancer (type 2, 35.1%), or synchronous with a recurrence (type 3, 33.3%). Type 1 (de novo, 14%) and type 4 (delayed metachronous after breast cancer recurrence, 17.5%) were less frequent. Among CAM patients, 49.1% were hormone receptor positive (HR+)/HER2-negative (HER2-), 22.8% HR-/HER2-, 10.5% HR+/HER2+, and 5.3% HR-/HER2+. Comparing CAM versus LABC, invasive ductal carcinoma (IDC) was more commonly seen in CAM (82.5% vs 66.5%), as was grade 3 (45.6% vs 35.5%), and triple negative (22.8% vs 13.5%). Conversely, in LABC, treatment of the primary index cancer more frequently included chemotherapy (CAM=71.9%, LABC=92.3%), mastectomy (CAM=54.4%, LABC 74.2%), and adjuvant radiation (CAM=73.7%, LABC=90.3%). On multivariable analysis adjusting for age, race/ethnicity, and hormone receptor status, both CAM and M1 had inferior survival to LABC (Table 1), but with a 2.4-fold difference for CAM (95% CI 1.42-4.07, p=0.001) versus a 6.3-fold difference for M1 (95% CI 4.29-9.23, p=< 0.001). Discussion In this contemporary, multi-institution study, we demonstrated that CAM patients selected for presumed curative intent treatment experienced improved OS when compared to stage IV (M1) patients. Our data adds additional support for re-evaluating the current stage IV designation, in favor of N3, and consideration of curative intent treatment in this disease. Table. Adjusted* Overall Survival Comparing Patients with Breast Cancer Contralateral Axillary Metastasis (CAM) to those with Locally Advanced Breast Cancer (LABC) and Metastatic Disease (M1) *Adjusted for age, race/ethnicity, hormone receptors. Citation Format: Meghan R. Flanagan, Stephanie Downs-Canner, Samantha Thomas, Astrid Botty van de bruele, Margaret Lillie, Kristalyn Gallagher, Tammeza Gibson, James Jakub, Alexandra Verosky, Sarah Tevis, Malia Brennan, Francys Verdial, Jennifer Q. Zhang, Leisha Elmore, Jennifer Plichta, Laura Rosenberger. A Multi-Institutional Review of Contralateral Axillary Metastases: Time for Reclassification as Local-Regional Event? [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 PO3-05-13.

Abstract PS05-09: A single-arm Phase II clinical study of fulvestrant combined with chemotherapy in the neoadjuvant treatment of HR+/HER2- locally advanced breast cancer

Abstract Background: HR+/HER2- breast cancer has been found to be less sensitive to neoadjuvant chemotherapy (NCT), leading to an objective response rate (ORR) of approximately 65%. Endocrine therapy combined with chemotherapy may help improve the ORR in these patients. The objective of this Phase II study was to evaluate the efficacy and safety of adding fulvestrant to NCT in patients with HR+/HER2- locally advanced breast cancer(LABC). Additionally, the study aimed to investigate the association of 18F-FES PET/CT and metabolites with efficacy. Methods: In this single-arm Phase II study, eligible patients were females with histologically confirmed HR+/HER2- LABC (Stage IIB-IIIC). Patients received fulvestrant (500 mg, on days 0, 14, 28, then every 28 days thereafter, every 4 weeks for six cycles) plus AC-T regimen, followed by surgery. Premenopausal women were administered a concomitant GnRH analogue. Patients underwent 18F-FES PET/CT before the initiation of fulvestrant, and plasma samples were collected for LC-MS analysis at baseline. The primary endpoint was ORR. Secondary endpoints included pathological complete response (tpCR) and safety. Results: From December 2020 to September 2022, 36 patients were enrolled. The median age was 53 years (range35-67). 78% were ECOG PS of 1, 69% were postmenopausal, 92% were nodal involved, and 83% were in stage III. After neoadjuvant therapy, the ORR was 86.1%. All patients completed the surgery, with a tpCR rate of 8.3% (3/36). 80.6% (29/36) patients were classified as Miller-Payne (MP) grade ≥3. Grade ≥3 treatment-emergent adverse events (TEAEs) occurred in 22% (8/36) of the participants. The most common TEAEs were neutropenia (13.9%) and leukopenia (8.3%). The expression of ER, PR, and Ki-67 in postoperative pathology significantly decreased compared to baseline (p < 0.05). Additionally, the change in ER expression was significantly correlated with the regression volume of primary breast tumors (R = 0.56, p = 0.0044). The decrease in ER value in patients with MP ≥ 4 was significantly larger than in patients with MP ≤ 3 (p = 0.0054). Among the 36 patients, 24 completed the 18F-FES PET/CT scan before initiating fulvestrant.The average SUVmax in primary breast lesions was 4.17 (range 1.00-12.80). The SUVmax of breast lesions was significantly correlated with clinical efficacy (p = 0.0018) and with changes in ER expression before and after treatment (R = 0.68, p = 0.00023). Meanwhile, the SUVmax of patients with MP ≥ 4 grade was significantly higher than that of patients with MP ≤ 3 grade (p=0.018). A total of 25 plasma samples were available for metabolic analysis. Among these samples, 13 differential metabolites were identified between patients with MP ≥ 4 grade and MP ≤ 3 grade, which were markedly enriched in 19 metabolic pathways. Conclusions: The addition of fulvestrant to NCT showed manageable toxicity and promising antitumor activity for patients with HR+/HER2- LABC. 18F-FES PET/CT might serve as a tool to predict the effectiveness of neoadjuvant combination therapy. Altered metabolites or metabolic pathways might be associated with the response to this combined treatment approach. Keywords: breast cancer, HR+/HER2-, fulvestrant, neoadjuvant treatment, 18F-FES PET/CT Citation Format: Qing Shao, Jing Wu, Ningning Zhang, Xiaohua Zeng. A single-arm Phase II clinical study of fulvestrant combined with chemotherapy in the neoadjuvant treatment of HR+/HER2- locally advanced 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 PS05-09.

Abstract PO4-12-03: PATIENT REPORTED OUTCOMES IN TERMS OF ARM AND SHOULDER FUNCTIONS AND QUALITY OF LIFE AND LYMPHEDEMA ARE AFFECTED BY THE STAGE, AND EXTENT OF AXILLARY SURGERY IN THE EARLY POSTOPERATIVE PERIOD OF PATIENTS WITH BREAST CANCER

Abstract This study evaluated whether lymphedema, patient-reported arm and shoulder morbidity and quality of life one year after axillary surgery are affected by stage or axillary surgery type between early stage patients and patients with locally advanced breast cancer who underwent surgery following neoadjuvant therapy. By determining the risk factors associated with severe lymphedema and deterioration of patient-reported outcomes, lymphedema could be prevented by early intervention to improve the prognosis of lymphedema and quality of life. Material and Methods: Between January 2021 and May 2022, a total of 253 breast cancer patients, 128 early stage and 125 locally advanced stage who underwent surgery including sentinel lymph node biopsy (SLNB) with/without axillary lymph node dissection (ALND) following neoadjuvant therapy were included in this study. The patients who underwent upfront surgery were defined as early-stage, and those who underwent surgery following neoadjuvant chemotherapy were considered as having locally advanced breast cancer (LABC) who have also participated in the prospective MF18-03 registry trial. Patients were prospectively evaluated by the SF-12 quality of life and QUICK-DASH hand, arm, and shoulder range of motion questionnaires and circumferential tape measurements of the arm width to evaluate the lymphedema before surgery, and 6 month- and 12-month assessments. The volume difference of 10% or more in the operated arm compared to the healthy arm was considered as lymphedema. Results: In the assessment of SF-12 quality of life questionnaire, there was a decrease in physical function scores at the 6th month despite recovery at the 12th month in both groups compared to the initial preoperative scores (p< 0,001). Moreover, patients with locally advanced breast cancer were found to have decreased SF-12 general health (p=0.024), vitality (p=0.034), and mental health scores in one year after surgery (p=0.004). Patients with mastectomy and locally advanced breast cancer were more likely to have a diminished arm and shoulder function as assessed with the QUICK-DASH questionnaire at the 6th and 12th months compared to those with breast conservation (6. month, p=0,009, 12. month, p=0.004), and early breast cancer, respectively (6. month, p=0.014, 12. month, p< 0.001) In the present cohort, lymphedema was detected in 19 (7.5%) patients including 16 cases with mild (11-20%), 2 cases with moderate (21-40%), and one case with severe (41-80%) lymphedema one year after surgery. Axillary dissection was found to be associated with an increased risk of lymphedema (SLNB, 5.0% vs ALND, 17.6%; p=0.005). Similarly, removal of >6 lymph nodes was also associated with an increased risk of lymphedema that was not statistically significant (<6 LNs, 6.4% vs >6LNs, 10.8%; p=0.277). Among those with LABC, however, patients with removal >6 LNs were more likely to have lymphedema (>6 LNs, 15.4% vs <6 LNs, 5.8%; p=0.096). Conclusion: These findings suggest that only an extensive axillary surgery was associated with an increased risk of breast cancer-related lymphedema. Patients with a mastectomy were more likely to have diminished arm and shoulder function compared to those with breast conservation. Furthermore, patients with locally advanced breast cancer were more likely to have a dispaired quality of life score and a limited arm and shoulder function regardless of the presence of lymphedema. Early prompt diagnosis and therapy of lymphedema can therefore potentially improve quality of life. Citation Format: Halime Gul Kilic, Selman Emiroglu, Ekin Ozgorgu, Mustafa Tukenmez, Atilla Bozdogan, Mahmut Muslumanoglu, Vahit Ozmen, Dilsad Sindel, Abdullah Igci, Aydan Oral, Neslihan Cabıoğlu. PATIENT REPORTED OUTCOMES IN TERMS OF ARM AND SHOULDER FUNCTIONS AND QUALITY OF LIFE AND LYMPHEDEMA ARE AFFECTED BY THE STAGE, AND EXTENT OF AXILLARY SURGERY IN THE EARLY POSTOPERATIVE PERIOD OF PATIENTS WITH 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 PO4-12-03.

Abstract PO5-26-04: The value of skin involvement in achieving of pCR in patients with locally advanced breast cancer

Abstract Objective: The management of patients with locally advanced breast cancer (LABC) with skin involvement (edema or thickening) continues to be one of the most controversial topics in mammology. The most recommended conventional treatment strategies include systemic therapy (chemotherapy/hormone therapy/biological agents) followed by local therapy (surgery and/or radiation therapy). However, approximately 1/3 of patients with locally advanced breast cancer are “resistant” to neoadjuvant chemotherapy (which is manifested by the persistence of skin involvement/edema/thickening). In this study, we aimed to identify the relationship between skin involvement and clinicopathological features of LABC patients. In particular, we sought to develop the algorithm for skin involvement measurement and examine the impact of skin involvement on the rate of pCR. Materials and methods: We performed a retrospective analysis of 182 patients diagnosed with LABC from 2010 to 2018 at N.N. Blokhin National Cancer Research Center. All patients were treated with neoadjuvant hormone- or chemotherapy and were considered as borderline for surgical resection because of partial skin edema. Ninety one women received surgery with consecutive radiotherapy (first group) and 50 women (second group) received radiotherapy (total dose 50 Gy) with consecutive surgery after systemic treatment. We developed the algorithm for skin involvement measurement, using a series of formulas. We further interrogated the impact of skin involvement on the rate of breast and lymph node pathological response in every group. Results: The median percentage of skin edema before systemic therapy was 76.3% in the first group and 70.1% in the second group. The median percentage of skin edema after systemic therapy was 62.3% in the first group and 69.1% in the second group. There wasn`t a statistically significant difference between the two groups (р=0,675 and р = 0,286, respectively). Breast pCR was seen in 19,7% (n=18) of the first group patients and partial response was seen in 72.6% (n=66). Breast pCR was seen in 30% (n=15) of the second group patients and partial response was seen in 70% (n=35). Results showed no significant differences between groups, р=0,342 and р = 0,12, respectively. Nodal pCR was reported in 23,9% (n=16) and partial response in 50,8% (n=34) of the 67 node-positive patients. Nodal pCR was reported in 31,6% (n=12) and partial response in 65,8% (n=29) of the 38 node-positive patients of the second group. There was no statistical difference in the groups, p >0,05. Conclusion: Increasing attention has been paid to LABC patients due to the clinical commonness and the complexity of treatment. Our study showed that LABC patients with incomplete clinical response to neoadjuvant systemic therapy can achieve pCR or partial response of tumor despite partial skin edema. In this study we developed the algorithm for skin involvement measurement. We hope that knowledge about volume of skin involvement revealed by this study might shed light on individualized therapies for these patients. In future, it allows to evaluate criteria of tumor resectability to improve patient selection. Therefore, prospective randomized trials are needed to improve optimization of the local treatment. Citation Format: Viktory Amosova, Alexander Petrovskiy, Oxana Trofimova, Mona Frolova, Alexey Rumyantsev. The value of skin involvement in achieving of pCR in patients with locally advanced 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 PO5-26-04.

Apriori prediction of chemotherapy response in locally advanced breast cancer patients using CT imaging and deep learning: transformer versus transfer learning

ObjectiveNeoadjuvant chemotherapy (NAC) is a key element of treatment for locally advanced breast cancer (LABC). Predicting the response to NAC for patients with Locally Advanced Breast Cancer (LABC) before treatment initiation could be beneficial to optimize therapy, ensuring the administration of effective treatments. The objective of the work here was to develop a predictive model to predict tumor response to NAC for LABC using deep learning networks and computed tomography (CT).Materials and methodsSeveral deep learning approaches were investigated including ViT transformer and VGG16, VGG19, ResNet-50, Res-Net-101, Res-Net-152, InceptionV3 and Xception transfer learning networks. These deep learning networks were applied on CT images to assess the response to NAC. Performance was evaluated based on balanced_accuracy, accuracy, sensitivity and specificity classification metrics. A ViT transformer was applied to utilize the attention mechanism in order to increase the weight of important part image which leads to better discrimination between classes.ResultsAmongst the 117 LABC patients studied, 82 (70%) had clinical-pathological response and 35 (30%) had no response to NAC. The ViT transformer obtained the best performance range (accuracy = 71 ± 3% to accuracy = 77 ± 4%, specificity = 86 ± 6% to specificity = 76 ± 3%, sensitivity = 56 ± 4% to sensitivity = 52 ± 4%, and balanced_accuracy=69 ± 3% to balanced_accuracy=69 ± 3%) depending on the split ratio of train-data and test-data. Xception network obtained the second best results (accuracy = 72 ± 4% to accuracy = 65 ± 4, specificity = 81 ± 6% to specificity = 73 ± 3%, sensitivity = 55 ± 4% to sensitivity = 52 ± 5%, and balanced_accuracy = 66 ± 5% to balanced_accuracy = 60 ± 4%). The worst results were obtained using VGG-16 transfer learning network.ConclusionDeep learning networks in conjunction with CT imaging are able to predict the tumor response to NAC for patients with LABC prior to start. A ViT transformer could obtain the best performance, which demonstrated the importance of attention mechanism.

Abstract PO4-22-09: Impact of time to surgery after neoadjuvant chemotherapy on pCR rate in locally-advanced breast cancer

Abstract Objective: Neoadjuvant chemotherapy along with surgical treatment are the important parts of treatment for locally advanced breast cancer. Extending the interval between the end of neoadjuvant chemotherapy and surgery may decrease tumor response in patients with locally advanced breast cancer. However, data if timing of surgery after neoadjuvant therapy affect the Pathologic complete response (pCR) rate is controversial. Materials and methods: We performed a retrospective analysis of 874 consecutive patients with IIIA-IIIC breast cancer that received neoadjuvant chemotherapy and surgery between 2000 and 2020 in N.N. Blokhin National Cancer Research Center. The median interval between the last injection of chemotherapy and surgery was 30 days (range 10 to 95 days). The variables were compared using log-rank statistics and Cox regression model. Results. Pathologic complete response (pCR) was registered in 250 (31,4%) patients. Univariate analysis showed that extending the interval between the end of neoadjuvant chemotherapy and surgery for each day were associated with decrease of probability of pCR (OR 0,982; p = 0,009). Patients with triple-negative and ER-/HER2+ achieved higher rates of pCR compared to luminal A subtype (p< 0,0001). Tumor grade, tumor size, Ki67 were independent predictive factors for tumor pCR (p < 0,001). Multivariate analysis also showed an independent negative effect of the time interval before surgery on the achieving pCR. Then the patients were stratified into three cohorts according to the time of surgery after neoadjuvant chemotherapy: < 22 days, 22-42 days, or >42 days. The odds ratio (OR) for pCR was 1 for < 22 days (reference), 0,833 for 22-42 days (p=0,332) and 0,576 for ≥43 days (p=0,033). Cox regression model demonstrated that the interval between the end of neoadjuvant chemotherapy and surgery (more than 42 days), tumor size, triple-negative and ER-/HER2+ were the significant predictive factors for pCR. Tumor grade, tumor size and age of patients were not independent predictive factors for in-breast pCR. Conclusion: Our study showed improved pCR if surgery was performed within 6 weeks after the end of neoadjuvant chemotherapy in locally advanced breast cancer. Results of multivariate logistic regression analysis to assess the probability of achieving complete pathomorphological regression Results of multivariate logistic regression analysis to assess the probability of achieving complete pathomorphological regression Citation Format: Alexander Petrovskiy, Viktory Amosova, Oxana Trofimova, Mona Frolova, Anastasya Soloshenko, Alexey Rumyantsev. Impact of time to surgery after neoadjuvant chemotherapy on pCR rate in locally-advanced 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 PO4-22-09.

Abstract PO3-27-01: Prediction of pathological complete response to neoadjuvant treatment in loco-regional advancedbreast cancer by using advanced PET/CT metabolic parameters

Abstract Prediction of pathological complete response to neoadjuvant treatment in loco-regional advanced breast cancer by using advanced PET/CT metabolic parameters. Abstract: Background: The standard treatment for locally advanced breast cancer (LABC) is neoadjuvant systemic therapy followed by surgery. The usefulness of FDG PET/CT for evaluating the treatment efficacy in breast cancer is well established; however, the role of quantitative functional PET/CT parameters, such as the metabolic tumor volume (MTV) and total lesion glycolysis (TLG), remains inconclusive. The aim of this study was to determine the correlation between quantitative functional parameters derived from PET/CT in LABC patients at staging and the response to neoadjuvant therapy. Methods: Seventy-eight consecutive patients (aged 25-82 y) with confirmed LABC (stages II-III) who underwent PET/CT as a part of their staging assessment and received neoadjuvant therapy followed by surgery were retrospectively included in this study. All patients underwent an FDG PET/CT at staging; and values of SUV max, SUV mean, MTV, and TLG were determined from the PET/CT studies. The patients were divided into two groups, based on the completeness of histopathologic response to neoadjuvant therapy, both in the primary tumor and axillary lymph nodes. Clinical, imaging and demographic data were collected from patient’s medical record. Results: A complete pathologic response (pCR) was achieved in 33/78 (42%) patients. Among patients with ER/PR positive, Her2-neu negative tumors, in 23/27 (85%) patients only partial pathologic response was reached; 91% of patients with ER/PR negative, Her2-neu positive and 43% of Triple-negative patients had complete pathological? response. For the primary breast tumor response, a higher SUV max, 10.7±5.34 for pCR vs. 7.24±4.62 for non-pCR group was measured, p-value=0.003; threshold value of 6.625. A higher SUV mean in the primary tumor resulted in a significantly higher rate of pCR, 5.95±2.36 vs 4,4±2.16, p=0.004, with a threshold value of 5.795. Neither MTV, not TLG were predictive parameters of the primary tumor response. For lymph nodes response, SUV max and SUV mean had no role in the prediction of pCR. Statistically significant difference however, was found between pCR and non-pCR in MTV values in the involved lymph nodes, with a median =2.13 cm³ [0-7.85] in pCR group vs 5.43 cm³ [3.11-15.3] in non-pCR, p=0.01 (threshold value 2.375) as well as in TLG measurements, with a median of 4.64 [0-19.8] vs. 12.7 [3.21-23.1], p=0.047, (25-75 IQR). Conclusion: Primary breast tumor SUV max/mean values have a significant correlation with the treatment response and threshold values were found. Low MTV and TLG measurements in lymph nodes may predict pCR. Neither MTV nor TLG had were found to have a significant role in the prediction of the primary tumor response. Citation Format: Maisun Shamya, Olga Kagna, Zohar Keidar, Tala Palchan-Hazan, Salem Billan, Roxolyana Abdah-Bortnyak. Prediction of pathological complete response to neoadjuvant treatment in loco-regional advancedbreast cancer by using advanced PET/CT metabolic parameters [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 PO3-27-01.

Abstract PO3-23-01: Triple-tracer Technique for Sentinel Lymph Node Biopsy of Breast Cancer after neoadjuvant Chemotherapy using Blue-dye, Radioisotope combined with Real-time Indocyanine green(ICG) Fluorescence Imaging Procrdures

Abstract Background: For post-neoadjuvant chemotherapy (NAC) patients (pts) with BC, sentinel lymph node biopsy (SNB) was recommended using the dual-tracer mapping technique (radioisotope plus blue dye) or placing a biopsy clip into the positive node at diagnosis and identifying it at the time of surgery due to SN identification rates (IR) were lower and false negative rates (FNR) were greater for pts with local advanced breast cancer (BC) than those of pts with early stage BC in the absence of NAC. Our previous clinical trial has indicated that the real-time ICG fluorescence (RT-ICG) imaging technique could improve the diagnostic sensitivity and detection accuracy for SNB. Methods: Between April 2019 and May 2022, post-NAC SNB were successfully identified in 45 of 52 patients with stage ⅡA to ⅢB (T1-T3, N0-2, M0) who had histologically confirmed breast cancer selected to receive NAC and the standard surgeries were performed after finishing NAC. The SNs was detected by conventional procedures of blue-dye (Indigo carmine) plus 99mTc radioisotope (dual-tracer) and combined with concurrent RT-ICG technique. Clinical node positive (cN+) was diagnosed by the radiologists using axillary ultrasound, MRI and/or CT scan or assessed by fine needle aspiration cytology (FNAC). The positivity of each single SN by each single tracer (blue dye, ICG, or isotope alone) was counted and identified, respectively. All patients are required to undergo SNB followed by completion axillary lymph node dissection (CND). Then the IR and FNR of each single tracer and their summation (triple tracer) were calculated by comparing the results of the SNB and the histopathology of the resection specimens of CND. Results: Among 45 post-NAC pts, the IR and FNR of each single procedure for SNB was 45.7% and 55.6% when used Indigo Carmine blue, 70.3% and 11.1% when used RI, 82.6% and 0 when used ICG fluorescence, respectively. In contrast, the total calculation of triple tracer showed that IR reached to 100% and FNR was 0, respectively. The IR of triple tracer were 83.9% and 100% for ypN0 and ypN(+) pts after NAC, both FNR were 0%. Conclusion: Our results suggested that the triple tracer technique combining blue dye, ICG, and isotope is effective method for detection of SNs in post-neoadjuvant cN+ BC pts. The IR and FNR of SNB might be improved by this multiple tracer mapping technique, particularly for pts with ypN(+) after NAC. It is considered that the multi-tracer can complement each other for what was not able to be traced and detected by the single tracer with one mapping material, and that result in totally the improvement of identification rate of SNB. Citation Format: Hidetaka Watanabe, Yuko Takao, Yuriko Katagiri, Rie Sugihara, Uhi Toh. Triple-tracer Technique for Sentinel Lymph Node Biopsy of Breast Cancer after neoadjuvant Chemotherapy using Blue-dye, Radioisotope combined with Real-time Indocyanine green(ICG) Fluorescence Imaging Procrdures [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 PO3-23-01.

Abstract PO2-08-02: Evaluation of predictive and prognostic value of androgen receptorexpression in breast cancer subtypes treated with neoadjuvantchemotherapy

Abstract Background Neoadjuvant chemotherapy is the standard treatment for local advanced breast cancer administered to shrink tumors and destroy undetected metastatic cells, thereby facilitating subsequent surgery. Previous studies have shown that AR may be used as a prognostic predictor in breast cancers, but its role in neoadjuvant therapy and the relationship with prognosis of different molecular subtypes of breast cancer need to be further explored. Methods We retrospectively evaluated 1231 breast cancer patients with complete medical records at Tianjin Medical University Cancer Institute and Hospital who were treated with neoadjuvant chemotherapy between January 2018 to December 2021. All the patients were selected for prognostic analysis. The follow-up time ranged from 12 to 60 months. We first analyzed the AR expression in different subtypes of breast cancer and its correlation with clinicopathological features. Meanwhile, the association of AR expression and pCR of different breast cancer subtypes was investigated. Finally, the effect of AR status on the prognosis of different subtypes of breast cancer after neoadjuvant therapy was analyzed. Results The positive rates of AR expression in HR +/HER2-, HR +/HER2 +, HR-/HER2 + and TNBC subtypes were 82.5%, 86.9%, 72.2% and 34.6%, respectively. Histological grade III (P = 0.014, OR = 1.862, 95% CI 1.137 to 2.562), ER positive expression (P = 0.002, OR = 0.381, 95% CI 0.102 to 0.754) and HER2 positive expression (P = 0.006, OR = 0.542, 95% CI 0.227 to 0.836) were independent related factors for AR positive expression. AR expression status was associated with pCR rate after neoadjuvant therapy only in subtype of TNBC. AR positive expression was independent protective factor for recurrence and metastasis in HR +/HER2- (P = 0.033, HR = 0.653, 95% CI 0.237 to 0.986) and HR +/HER2 + breast cancer (P = 0.012, HR = 0.803, 95% CI 0.167 to 0.959), but was independent risk factors for recurrence and metastasis in TNBC (P = 0.015, HR = 4.551, 95% CI 2.668 to 8.063). AR positive expression is not an independent predictor of HR-/HER2 + breast cancer. Conclusions AR expressed the lowest in TNBC, but it could be a potential marker for the prediction of pCR in neoadjuvant therapy. AR negative patients had a higher pCR rate. AR positive expression was an independent risk factor for pCR in TNBC after neoadjuvant therapy (P = 0.017, OR = 2.758, 95% CI 1.564 to 4.013). In HR +/HER2- subtype and in HR +/HER2 + subtype, the DFS rate in AR positive patients and AR negative patients was 96.2% vs 89.0% (P = 0.001, HR = 0.330, 95% CI 0.106 to 1.034) and was 96.0% vs 85.7% (P= 0.002, HR = 0.278, 95% CI 0.082 to 0.940), respectively. However, in HR-/HER2 + and TNBC subtypes, the DFS rate in AR positive patients and AR negative patients was 89.0% vs 95.9% (P = 0.102, HR = 3.211, 95% CI 1.117 to 9.224) and 75.0% vs 93.4% (P < 0.001, HR = 3.706, 95% CI 1.681 to 8.171), respectively. In HR +/HER2- and HR +/HER2 + breast cancer, AR positive patients had a better prognosis, however in TNBC, AR-positive patients have a poor prognosis Citation Format: Jin Zhang. Evaluation of predictive and prognostic value of androgen receptorexpression in breast cancer subtypes treated with neoadjuvantchemotherapy [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 PO2-08-02.

Implementing Standard Diagnosis and Treatment for Locally Advanced Breast Cancer Through Global Research in Latin America: Results From a Multicountry Pragmatic Trial.

Breast cancer mortality rates in Latin America (LA) are higher than those in the United States, possibly because of advanced disease presentation, health care disparities, or unfavorable molecular subtypes. The Latin American Cancer Research Network was established to address these challenges and to promote collaborative clinical research. The Molecular Profiling of Breast Cancer Study (MPBCS) aimed to evaluate the clinical characteristics and treatment outcomes of LA participants with locally advanced breast cancer (LABC). The MPBCS enrolled 1,449 participants from Argentina, Brazil, Chile, Mexico, and Uruguay. Through harmonized procedures and quality assurance measures, this study evaluated clinicopathologic characteristics, neoadjuvant chemotherapy response, and survival outcomes according to residual cancer burden (RCB) and the type of surgery. Overall, 711 and 480 participants in the primary surgery and neoadjuvant arms, respectively, completed the 5-year follow-up period. Overall survival was independently associated with RCB (worse survival for RCBIII-adjusted hazard ratio, 8.19, P < .001, and RCBII [adjusted hazard ratio, 3.69, P < .008] compared with RCB0 [pathologic complete response or pCR]) and type of surgery (worse survival in mastectomy than in breast-conserving surgery [BCS], adjusted hazard ratio, 2.97, P = .001). The hormone receptor-negative-human epidermal growth factor receptor 2-positive group had the highest proportion of pCR (48.9%). The analysis of the ASCO Quality Oncology Practice Initiative breast module revealed high compliance with pathologic standards but lower adherence to treatment administration standards. Notably, compliance with trastuzumab administration varied widely among countries (33.3%-88.7%). In LABC, we demonstrated the survival benefit of BCS and the prognostic effect of the response to available neoadjuvant treatments despite an important variability in access to key treatments. The MPBCS represents a significant step forward in understanding the real-world implementation of oncologic procedures in LA.

Association of body composition and survival in patients with locally advanced breast cancer: a historical cohort study.

Altered body composition has been attributed to major health problems globally, particularly in patients with cancer. To date, there have not been sufficient indices for body compositions in predicting the survival of locally advanced breast cancer (LABC). To assess the association between body composition and overall survival (OS) as well as disease-free survival (DFS) in patients with LABC. A retrospective study was conducted of patients with LABC diagnosed between 2010 and 2018. Body composition parameters, including skeletal muscle and adiposity parameters, were measured using computed tomography at the L3 vertebra using in-house software developed by MATLAB and freeware Python 3.6.13. The association between body composition and OS and DFS were analyzed using a log-rank test and multivariate Cox-proportional hazard regression. Of 199 patients, 72 (36%) died during the follow-up period (range = 3.8-150.7 months). Median survival was 101 months. Low visceral-to-subcutaneous ratio ≤0.3 (adjusted hazard ratio [aHR] = 2.57, 95% confidence interval [CI] = 1.51-4.37; aHR = 2.46, 95% CI = 1.33-4.56), and high composite fat (aHR = 3.26, 95% CI = 1.69-6.29; aHR = 2.19, 95% CI = 1.11-4.3) were associated with lower OS and DFS. Positive lymph nodes ≥3, progesterone receptor negative, and total radiation dose >5000 cGy significantly decreased both OS and DFS. A history of previous treatment before body composition assessment and surgery had a protective effect on OS and DFS. No association of sarcopenia, body mass index, and adiposity areas with survival outcomes was observed. Low visceral-to-subcutaneous ratio and high composite fat were independent prognostic factors for OS and DFS in patients with LABC. However, other body composition parameters showed no effect on survival.

Locoregional recurrence and survival of breast-conserving surgery compared to mastectomy following neoadjuvant chemotherapy in operable breast cancer.

The risk of locoregional recurrence (LRR) and the long-term prognosis of breast-conserving surgery (BCS) after neoadjuvant chemotherapy (NAC) are still controversial. This study aimed to evaluate oncological outcomes for patients undergoing BCS after NAC and determine LRR and survival predictors. This study was a retrospective cohort study of patients with locally advanced breast cancer (LABC) who received NAC and underwent BCS or mastectomy from June 2011 to November 2020. LRR, disease-free survival (DFS), and overall survival (OS) were compared in patients undergoing BCS or mastectomy. Univariate and multivariate analyses were performed to determine LRR, DFS, and OS predictors. A total of 585 patients were included, of whom 106 (18.1%) underwent BCS and 479 (81.9%) underwent a mastectomy. The LRR rate was 11.3% in the BCS group and 16.3% in the mastectomy group, revealing no significant difference(p = 0.200). In patients who underwent BCS, clinical lymph node status, histological grade and pathological complete response (pCR) were independent factors to predict LRR. There was no significant difference in DFS and OS between the BCS and the mastectomy groups. Multivariable analysis showed that lymph node status, histological grade, molecular subtypes, pCR and Miller&Payne (M&P) classification were independent predictors of DFS. Lymph node status, molecular subtypes and pCR were independent predictors of OS. BCS or mastectomy was not an independent predictor of DFS or OS. Compared with mastectomy, BCS after NAC may not increase the risk of local recurrence or mortality, BCS can be performed in selected patients with small tumor size and good response to NAC.

Oncological outcomes of post neo adjuvant chemotherapy breast conservation surgery in patients with locally advanced breast cancer

Abstract Introduction: Breast cancer in India is phenotypically different with locally advanced breast cancers (LABCs) forming 30–50% of all cases. Use of neoadjuvant chemotherapy (NACT), among other things has contributed to surgeons using breast conservation surgery (BCS) in very selected patients with good results. Herein, we describe the oncological outcomes of BCS in LABC patients undergoing surgery post NACT. Patients and Methods: This is an ambispective observational cohort study conducted between January 1996 and December 2019 after approval by Institute Ethics Committee, to study the ipsilateral breast tumor recurrence (IBTR) in patients with LABC undergoing BCS post NACT. The secondary objectives were to ascertain the disease-free survival (DFS) and overall survival (OS) and factors associated with IBTR in these patients. Patients were staged according to the anatomic American Joint Committee on Cancer (AJCC) VIII Tumor Node Metastasis (TNM) classification and clinic-demographic, pathologic, treatment, and follow-up details were noted. Results: Out of 822 patients with LABC, 71 patients undergoing BCS post NACT were included. Average tumor size at presentation was 6.43 cm. The most common T stage was T3 (57.7%) and N stage was N1 (53.5%). The most common stage group was IIIB in 40.8%. Around 75% received anthracycline-based NACT with 28.2% having a complete clinical response. A pathological complete response was seen in 16 patients (22.5%). The mean follow-up duration was 6.14 years. A total of 25 patients had recurrences: five patients had IBTR (7%) and four had a local with regional recurrence. Two, 5, and 10 years OS were 94.0, 83.8, and 61.9%, respectively, and DFS were 87.8, 67.1, and 50.6%, respectively. A higher clinical T stage was associated with poor DFS (p = 0.01). The risk of IBTR was not found to significantly correlate with any of the standard prognostic factors. Conclusion: BCS post NACT in suitably selected patients of LABC is a safe and viable option without adversely affecting oncological outcomes.

Discussing the safety and effectiveness of transcatheter arterial embolization combined with intravenous chemotherapy in treating locally advanced breast cancer

To investigate the efficacy and safety of drug-eluting bead-transarterial chemoembolization (DEB-TACE) combined with systemic chemotherapy in HR+/Her2− locally advanced breast cancer (LABC) patients. A controlled study was conducted on LABC patients treated at Jianyang People’s Hospital and the First Affiliated Hospital of Chengdu Medical College from December 2020 to June 2022. The patients were randomly divided into the experimental group and the control group. The experimental group received DEB-TACE combined with the TAC regimen (175 mg/m2 paclitaxel-loaded albumin, 50 mg/m2 Doxorubicin, and 500 mg/m2 cyclophosphamide), while the control group received the TAC regimen intravenously. The therapeutic efficacy was evaluated using the mRECIST criteria. Statistical analysis was performed using SPSS 22.0 software, and baseline characteristics, overall response rate (ORR), pathological complete response (PCR), adverse reactions, and complications were compared between the two groups using paired t-test and chi-square test. A total of 60 patients were included, with 30 patients in the experimental group (50%) and 30 patients in the control group (50%). After the first treatment, the ORR was 90% in the experimental group and 60% in the control group (P < 0.05). The overall ORR was 100% in the experimental group and 83% in the control group (P < 0.05). PCR was achieved in 14 patients (47%) in the experimental group and 4 patients (13%) in the control group. The main adverse reactions in the experimental group were skin blistering, pigmentation, and pain. There was no statistically significant difference in vomiting and grade II or above bone marrow suppression between the two groups. No grade III or above adverse events occurred in either group. The comparison of tumor shrinkage between the two groups was P = 0.051, and axillary lymph node shrinkage was P < 0.05. The use of drug-eluting beads in combination with neoadjuvant chemotherapy is a feasible and safe treatment option for locally advanced breast cancer patients.

The Role of Level III Dissection in Locally Advanced Breast Cancer following Neoadjuvant Chemotherapy—A Prospective Study

Breast cancer is the most common female cancer in India, with a significant number presenting as locally advanced breast cancer (LABC). Level III clearance is routinely performed in our institute in LABC following neoadjuvant chemotherapy (NACT). In our previous retrospective study, level III positivity rate was 15.5%. We aim to prospectively assess level III positivity rate in LABC patients post-NACT. This is a prospective study of female patients with LABC (defined as cT3N1–3M0 or cT4N0–3M0 or cTanyN2,3M0) who received NACT and underwent surgery including level III dissection from November 2019 to October 2021. Data collected included age, menopausal status, TNM stage at presentation, grade, hormone receptor and HER2 status, treatment response, ycT and ycN stage, and final histopathology. Univariate and multivariate analysis was undertaken. p-Value less than or equal to 0.05 was considered significant. Study recruited 598 patients. Level III node positivity rate was 8.4%. The clinical complete response rate (cCR) was 36% (215/598). On univariate analysis, significant association was present between level III node and cCR (p &lt; 0.01), ycT0 stage (p = 0.001), ycN0 stage (p = 0.028), level II node positivity (p = 0.001), ypT stage (p = 0.001), and ypN stage (p = 0.001). On multivariate analysis, significant association was present between level III node and ycT stage (p &lt; 0.001), ypT stage (p = 0.001), and ypN stage (p = 0.001). Level III positivity rate in LABC post-NACT is high. In patients with advanced ycT stage, it would be advisable to offer complete axillary dissection including level III. Level III dissection may be avoided in patients with ycT0 or ycN0 or with cCR.

HER2-positive is an independent indicator for predicting pathological complete response to neoadjuvant therapy and Ki67-changed after neoadjuvant chemotherapy predicts favorable prognosis in Chinese women with locally advanced breast cancer.

The growing body of evidence suggests that breast cancer (BC) who achieve pathological complete response (pCR) after neoadjuvant chemotherapy (NAC) may experience a more favorable prognosis. The objective of this study is to investigate the correlation between clinicopathologic parameters of locally advanced breast cancer (LABC) patients and the outcomes of NAC, with the aim of identifying predictive indicators for pCR. Additionally, we seek to examine the conversion of IHC markers in pCR patients following NAC and its impact on the prognosis of BC patients. We conducted a study involving 126 patients with LABC. Clinicopathological parameters associated with pCR were subjected to univariate and multivariate analysis. Kaplan-Meier (KM) curves and the log-rank test were used to compare the statistical difference in prognosis in different groups of patients. Additionally, we used difference and consistency tests to examine the conversion of immunohistochemistry (IHC) markers following NAC. The status of estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2) and molecular subtypes of BC were associated with pCR in the univariate analysis (all P < .05), which may be potential markers to predict pCR. HER2 was identified as an independent factor for predicting pCR in the multivariate analysis. The pCR rate of HER2-positive patients who received NAC combined targeted therapy was higher than that of patients who only received NAC (P = .003). The disease-free survival (DFS) rate of TNBC patients who achieved pCR was significantly higher than that of non-pCR TNBC patients (P = .026). The IHC marker conversion after NAC mainly existed in PR (P = .041). Ki67 expression decreased in the luminal B subtype and increased in the HER2 enriched subtype after NAC (all P < .001). Patients with Ki67 expression change after NAC had longer overall survival (OS) and DFS than unchanged patients (all P < .05). HER2-positive is an independent indicator for predicting pCR, and HE2-positive patients who received NAC combined targeted therapy were favorable to achieving pCR. IHC markers of BC patients exhibit varying degrees of alterations after NAC, and changes in Ki67 expression after NAC could serve as a marker to predict a better prognosis.

Transfer learning of pre-treatment quantitative ultrasound multi-parametric images for the prediction of breast cancer response to neoadjuvant chemotherapy

Locally advanced breast cancer (LABC) is a severe type of cancer with a poor prognosis, despite advancements in therapy. As the disease is often inoperable, current guidelines suggest upfront aggressive neoadjuvant chemotherapy (NAC). Complete pathological response to chemotherapy is linked to improved survival, but conventional clinical assessments like physical exams, mammography, and imaging are limited in detecting early response. Early detection of tissue response can improve complete pathological response and patient survival while reducing exposure to ineffective and potentially harmful treatments. A rapid, cost-effective modality without the need for exogenous contrast agents would be valuable for evaluating neoadjuvant therapy response. Conventional ultrasound provides information about tissue echogenicity, but image comparisons are difficult due to instrument-dependent settings and imaging parameters. Quantitative ultrasound (QUS) overcomes this by using normalized power spectra to calculate quantitative metrics. This study used a novel transfer learning-based approach to predict LABC response to neoadjuvant chemotherapy using QUS imaging at pre-treatment. Using data from 174 patients, QUS parametric images of breast tumors with margins were generated. The ground truth response to therapy for each patient was based on standard clinical and pathological criteria. The Residual Network (ResNet) deep learning architecture was used to extract features from the parametric QUS maps. This was followed by SelectKBest and Synthetic Minority Oversampling (SMOTE) techniques for feature selection and data balancing, respectively. The Support Vector Machine (SVM) algorithm was employed to classify patients into two distinct categories: nonresponders (NR) and responders (RR). Evaluation results on an unseen test set demonstrate that the transfer learning-based approach using spectral slope parametric maps had the best performance in the identification of nonresponders with precision, recall, F1-score, and balanced accuracy of 100, 71, 83, and 86%, respectively. The transfer learning-based approach has many advantages over conventional deep learning methods since it reduces the need for large image datasets for training and shortens the training time. The results of this study demonstrate the potential of transfer learning in predicting LABC response to neoadjuvant chemotherapy before the start of treatment using quantitative ultrasound imaging. Prediction of NAC response before treatment can aid clinicians in customizing ineffectual treatment regimens for individual patients.

Inflammatory indicators as a prognostic factor of clinical response in locally advanced breast cancer (LABC) patients receiving neoadjuvant chemotherapy (NAC)

ObjectivesBreast cancer is a prevalent and fatal cancer worldwide. Neoadjuvant chemotherapy is a treatment option used to reduce tumor size in patients with locally advanced breast cancer. The neutrophil–lymphocyte ratio (NLR), lymphocyte–monocyte ratio (LMR), and platelet–lymphocyte ratio (PLR) are inflammatory markers that have been studied as prognostic factors in breast cancer. This cross-sectional study aimed to investigate the role of NLR, LMR, and PLR in the clinical response to neoadjuvant chemotherapy in women with locally advanced breast cancer. Materials and methodsWe used a cross-sectional research design for this study with the aim of observing the relation between NLR, LMR, and PLR and the clinical response of neoadjuvant chemotherapy. The study was conducted in Cipto Mangunkusumo General Hospital. We analyzed the medical records of 84 patients treated with neoadjuvant chemotherapy between 2016 and 2021. ResultsOur study found that majority of the subjects receives CAF combination of NAC with inoperable breast cancer. Most of the subjects have luminal B type of breast cancer and no clinical response to chemotherapy regimen. Surgery has significant association with clinical response in patients receiving NAC (P = <.001). There are no significant correlation between NLR, LMR, and PLR with clinical response to neoadjuvant chemotherapy. However, we did observe a significant association between NLR and 1-year mortality rate. ConclusionIn conclusion, significant association between NLR and 1-year morality rate suggest that NLR may serve as a useful prognostic factor in breast cancer patients receiving neoadjuvant chemotherapy.

Quantitative ultrasound radiomics guided adaptive neoadjuvant chemotherapy in breast cancer: early results from a randomized feasibility study.

In patients with locally advanced breast cancer (LABC) receiving neoadjuvant chemotherapy (NAC), quantitative ultrasound (QUS) radiomics can predict final responses early within 4 of 16-18 weeks of treatment. The current study was planned to study the feasibility of a QUS-radiomics model-guided adaptive chemotherapy. The phase 2 open-label randomized controlled trial included patients with LABC planned for NAC. Patients were randomly allocated in 1:1 ratio to a standard arm or experimental arm stratified by hormonal receptor status. All patients were planned for standard anthracycline and taxane-based NAC as decided by their medical oncologist. Patients underwent QUS imaging using a clinical ultrasound device before the initiation of NAC and after the 1st and 4th weeks of treatment. A support vector machine-based radiomics model developed from an earlier cohort of patients was used to predict treatment response at the 4th week of NAC. In the standard arm, patients continued to receive planned chemotherapy with the treating oncologists blinded to results. In the experimental arm, the QUS-based prediction was conveyed to the responsible oncologist, and any changes to the planned chemotherapy for predicted non-responders were made by the responsible oncologist. All patients underwent surgery following NAC, and the final response was evaluated based on histopathological examination. Between June 2018 and July 2021, 60 patients were accrued in the study arm, with 28 patients in each arm available for final analysis. In patients without a change in chemotherapy regimen (53 of 56 patients total), the QUS-radiomics model at week 4 of NAC that was used demonstrated an accuracy of 97%, respectively, in predicting the final treatment response. Seven patients were predicted to be non-responders (observational arm (n=2), experimental arm (n=5)). Three of 5 non-responders in the experimental arm had chemotherapy regimens adapted with an early initiation of taxane therapy or chemotherapy intensification, or early surgery and ended up as responders on final evaluation. The study demonstrates the feasibility of QUS-radiomics adapted guided NAC for patients with breast cancer. The ability of a QUS-based model in the early prediction of treatment response was prospectively validated in the current study. clinicaltrials.gov, ID NCT04050228.