Assessment of Pathological Response of Breast Carcinoma in Modified Radical Mastectomy Specimens after Neoadjuvant Chemotherapy

An optimised patient-derived explant platform for breast cancer reflects clinical responses to chemotherapy and antibody-directed therapy

Breast Cancer is the most common cancer among women globally. Despite significant improvements in overall survival, many tumours are refractory to therapy and so novel approaches are required to improve patient outcomes. We have evaluated patient-derived explants (PDEs) as a novel preclinical platform for breast cancer (BC) and implemented cutting-edge digital pathology and multi-immunofluorescent approaches for investigating biomarker changes in both tumour and stromal areas at endpoint. Short-term culture of intact fragments of BCs as PDEs retained an intact immune microenvironment, and tumour architecture was augmented by the inclusion of autologous serum in the culture media. Cell death/proliferation responses to FET chemotherapy in BC-PDEs correlated significantly with BC patient progression-free survival (p = 0.012 and p = 0.0041, respectively) and cell death responses to the HER2 antibody therapy trastuzumab correlated significantly with HER2 status (p = 0.018). These studies show that the PDE platform combined with digital pathology is a robust preclinical approach for informing clinical responses to chemotherapy and antibody-directed therapies in breast cancer. Furthermore, since BC-PDEs retain an intact tumour architecture over the short-term, they facilitate the preclinical testing of anti-cancer agents targeting the tumour microenvironment.

Evaluation of Histomorphological Changes in Breast Cancer Post-Neoadjuvant Chemotherapy

Breast cancer, a leading cause of global female mortality, demands comprehensive diagnostic and therapeutic strategies. This study delves into the nuanced realm of post-neoadjuvant chemotherapy breast cancer specimens, emphasizing the imperative need for pathologists to discern stromal and nuclear alterations adeptly. The investigation, encompassing 100 female patients with a mean age of 47.5 years, elucidates the demographic and clinicopathological parameters. Predominantly presenting as palpable lumps (85%), invasive ductal carcinoma emerged as the predominant histological type (98%). The primary focus of the study revolves around the morphological changes post-neoadjuvant chemotherapy, with a meticulous qualitative analysis encompassing stromal elements (fibrosis, elastosis, calcification) and nuclear features (pyknosis, hyperchromasia). Notably, the response to chemotherapy, classified by the International Union against Cancer criteria, delineates a substantial pathological complete response (55%), partial response (35%), and limited non-response (10%). The therapeutic landscape includes a majority of cases undergoing extensive chemotherapy cycles, primarily featuring the cyclophosphamide, doxorubicin, and paclitaxel regimen. Remarkably, this investigation unveils fibrosis (63%) and elastosis/collagenization (51%) as prevalent stromal changes, while pyknosis (58%) and hyperchromasia (48%) dominate nuclear alterations. In conclusion, this retrospective study provides a comprehensive overview of post-neoadjuvant chemotherapy breast cancer specimens, shedding light on the intricate interplay of clinical parameters, treatment responses, and histopathological changes. The findings underscore the pivotal role of pathologists in accurately diagnosing and grading tumors in the evolving landscape of breast cancer management.

Neoadjuvant chemotherapy for breast cancer: an evaluation of its efficacy and research progress

Neoadjuvant chemotherapy (NAC) for breast cancer is widely used in the clinical setting to improve the chance of surgery, breast conservation and quality of life for patients with advanced breast cancer. A more accurate efficacy evaluation system is important for the decision of surgery timing and chemotherapy regimen implementation. However, current methods, encompassing imaging techniques such as ultrasound and MRI, along with non-imaging approaches like pathological evaluations, often fall short in accurately depicting the therapeutic effects of NAC. Imaging techniques are subjective and only reflect macroscopic morphological changes, while pathological evaluation is the gold standard for efficacy assessment but has the disadvantage of delayed results. In an effort to identify assessment methods that align more closely with real-world clinical demands, this paper provides an in-depth exploration of the principles and clinical applications of various assessment approaches in the neoadjuvant chemotherapy process.

Pathologic response and residual tumor cellularity after neo-adjuvant chemotherapy predict prognosis in breast cancer patients

INTRODUCTION

Residual tumor cellularity (RTC) and pathologic complete response (pCR) after neo-adjuvant chemotherapy (NAC) are prognostic factors associated with improved outcomes in breast cancer (BC). However, the majority of patients achieve partial pathologic response (pPR) and no clear correlation between RTC patterns and outcomes was described. Our aims were to define predictive factors for pCR and compare different outcomes of patients with pCR or pPR and with different RTC patterns.

MATERIALS AND METHODS

Baseline and post-NAC demographics, clinicopathological characteristics, post-operative data, survival and recurrence status were recorded from our institutional database. A multivariable analysis was performed using a logistic regression model to identify independent predictors of pCR. Disease-free survival (DFS), distant disease-free survival (DDFS), and overall survival (OS) analyses were performed using the Kaplan-Meier method.

RESULTS

Overall, of the 495 patients analyzed, 148 (29.9%) achieved pCR, 347 (70.1%) had pPR, and the median RTC was 40%. Multivariable analysis identified 3 independent factors predictive of pCR: tumor stage before NAC (cT1-2 84.5% versus cT3-4 15.5%), BC sub-type (HER2-positive 54.7% versus triple-negative 29.8% versus luminal-like 15.5%), and vascular invasion (absence 98.0% versus presence 2.0%). We found statistically significant longer DFS, DDFS, and OS in patients with pCR and with RTC <40%; no difference was observed in terms of OS between RTC <40% and RTC ≥40% groups.

CONCLUSIONS

Tumor stage before NAC, BC sub-type, and vascular invasion are significant and independent factors associated with pCR. Patients with pCR and with RTC <40% have longer DFS, DDFS, and OS compared with patients with pPR.

Assessing the Correlation of Rate of Pathological Complete Response and Outcome in Post Neoadjuvant Chemotherapy Setting and Molecular Subtypes of Breast Cancer

Background Neoadjuvant chemotherapy (NAC) is being widely used in treating breast cancer (BC). This study aimed to analyze the correlation between clinicopathological features, immunohistochemistry (IHC)-based molecular subtypes, and the pathological response to NAC and its relationship with disease-free survival (DFS) and overall survival (OS). Materials and methods A retrospective analysis of 211 breast cancer patients who received NAC between 2008 and 2018 was performed. Tumors were classified by IHC into luminal A, luminal B, human epidermal growth factor receptor 2 (HER2)-enriched, and triple-negative subtypes. The chi-square test was used to assess the association between pathological response and clinicopathological parameters. Cox regression analysis was used to assess factors related to DFS and OS. Results Post NAC, 19.4% of patients achieved a pathologic complete response (pCR). Estrogen receptor (ER), progesterone receptor (PR), HER2 (p<0.001, 0.005, and 0.02), Ki67 (p=0.03), molecular subtypes (p<0.001), T stage (p=0.04), and N stage (p=0.01) were significantly associated with pathological response. The rate of pCR was highest among HER2-enriched and triple-negative tumors (45.2% and 28%, respectively) with OR=0.13 and p<0.001 for the HER2-enriched subtype. Patients with pCR were 61% less likely to develop metastasis (adjusted hazard ratio [aHR]=0.39, p=0.06, 95% CI=0.14-1.06) and were significantly associated with better OS (aHR=0.07, p=0.02, 95% CI=0.01-0.61). Patients who were ≤40 years old (aHR=2.1, p=0.01), with T4 (aHR=3.4, p=0.02), grade 3 (aHR=2.5, p=0.01), and node-positive disease (HR=2.24, p=0.02) were at an increased risk of developing metastasis. High Ki67 was found to be significantly associated with better DFS (p=0.006). Conclusion HER2-enriched and triple-negative BC were associated with a higher rate of pCR. Patients with pCR had significantly better DFS and OS. Younger age, advanced stage, higher grade, and lymph node involvement were risk factors for metastasis.

Predicting dynamic response to neoadjuvant chemotherapy in breast cancer: a novel metabolomics approach

Neoadjuvant chemotherapy (NACT) outcomes vary according to breast cancer (BC) subtype. Since pathologic complete response is one of the most important target endpoints of NACT, further investigation of NACT outcomes in BC is crucial. Thus, identifying sensitive and specific predictors of treatment response for each phenotype would enable early detection of chemoresistance and residual disease, decreasing exposures to ineffective therapies and enhancing overall survival rates. We used liquid chromatography−high‐resolution mass spectrometry (LC‐HRMS)‐based untargeted metabolomics to detect molecular changes in plasma of three different BC subtypes following the same NACT regimen, with the aim of searching for potential predictors of response. The metabolomics data set was analyzed by combining univariate and multivariate statistical strategies. By using ANOVA–simultaneous component analysis (ASCA), we were able to determine the prognostic value of potential biomarker candidates of response to NACT in the triple‐negative (TN) subtype. Higher concentrations of docosahexaenoic acid and secondary bile acids were found at basal and presurgery samples, respectively, in the responders group. In addition, the glycohyocholic and glycodeoxycholic acids were able to classify TN patients according to response to treatment and overall survival with an area under the curve model > 0.77. In relation to luminal B (LB) and HER2+ subjects, it should be noted that significant differences were related to time and individual factors. Specifically, tryptophan was identified to be decreased over time in HER2+ patients, whereas LysoPE (22:6) appeared to be increased, but could not be associated with response to NACT. Therefore, the combination of untargeted‐based metabolomics along with longitudinal statistical approaches may represent a very useful tool for the improvement of treatment and in administering a more personalized BC follow‐up in the clinical practice.

Contrast enhanced ultrasound quantitative parameters for assessing neoadjuvant chemotherapy response in patients with locally advanced breast cancer

OBJECTIVES

To evaluate the role of contrast-enhanced ultrasound (CEUS) quantitative parameters in predicting neoadjuvant chemotherapy (NACT) response in patients with locally advanced breast cancer (LABC).

METHODS

30 patients with histologically proven LABC scheduled for NACT were recruited. CEUS was performed using a contrast bolus of 4.8 ml and time intensity curves (TICs) were obtained by contrast dynamics software. CEUS quantitative parameters assessed were peak enhancement (PE), time-to-peak (TTP), area under the curve (AUC) and mean transit time (MTT). The parameters were documented on four consecutive instances: before NACT and 3 weeks after each of the three cycles. The gold-standard was pathological response using Miller Payne Score obtained pre NACT and post-surgery.

RESULTS

A decrease in mean values of PE and an increase in mean values of TTP and MTT was observed with each cycle of NACT among responders. Post each cycle of NACT (compared with baseline pre-NACT), there was a statistically significant difference in % change of mean values of PE, TTP and MTT between good responders and poor responders (p-value < 0.05). The diagnostic accuracy of TTP post-third cycle was 87.2% (p = 0.03), and MTT post--second and third cycle was 76.7% (p = 0.004) and 86.7% (p = 0.006) respectively.

CONCLUSION

In responders, a decrease in the tumor vascularity was reflected in the CEUS quantitative parameters as a reduction in PE, and a prolongation in TTP, MTT.

ADVANCES IN KNOWLEDGE

Prediction of NACT response by CEUS has the potential to serve as a diagnostic modality for modification of chemotherapy regimens during ongoing NACT among patients with LABC, thus affecting patient prognosis.

Concordance Between Clinical and Pathological Response Assessment After Neo-Adjuvant Chemotherapy in Patients With Invasive Lobular Carcinoma

Background Neo-adjuvant chemotherapy (NAC) is frequently administered in breast carcinoma patients. The clinical response to NAC guides further treatment. The pathological response is not only an independent prognostic factor, but it also guides further treatment and prognosis. Objectives The aim of our study was to find the degree of concordance between clinical and pathological response assessments after NAC in Invasive lobular Carcinoma (ILC) cases by using World Health Organization (WHO) criteria and different pathological systems, respectively. We also tried to identify any useful parameter of clinical assessment that could better correlate with pathologic assessment and provide a better estimation of residual tumor. Methods This retrospective study was conducted on 26 ILC tumors diagnosed in 24 patients who were treated with NAC followed by surgical resection between January 2009 and December 2020. Medical records and microscopy glass slides were reviewed for clinical and pathological response assessments, respectively. Results The pre-treatment tumor area ranged from 1.8-255 cm² and the mean±SD was 52.2±66.8 cm². After NAC, complete clinical response was observed in four (15.3%) cases. The clinically assessed mean tumor area significantly reduced from 52.2±66.8 cm² to 17.2±22.6 cm² (p-value<0.001). The pathologically assessed mean tumor area (27.4±24.1 cm²) didn't differ significantly from the clinically assessed mean tumor area (17.2±22.6 cm²) (p-value=0.114). Pathologically, the majority of the cases showed partial response, and a complete pathological response was achieved in only two (7.7%) cases. The concordance rates between clinical assessment by the WHO method and pathological assessment of the breast using the Sataloff method, Miller-Payne (MP) system, Residual Cancer Burden system, and Chevallier method were 26.7%, 15.8%, 9%, and 3.5%, respectively, with insignificant p-values. Percentage reduction in clinical size and percentage reduction in tumor cellularity differed significantly (p-value=0.038). Conclusion Clinical response assessment provides a less accurate estimation of residual disease, as it shows poor concordance with pathological assessment using different assessment systems/methods.

Plasma polymerized nanoparticles effectively deliver dual siRNA and drug therapy in vivo

Multifunctional nanocarriers (MNCs) promise to improve therapeutic outcomes by combining multiple classes of molecules into a single nanostructure, enhancing active targeting of therapeutic agents and facilitating new combination therapies. However, nanocarrier platforms currently approved for clinical use can still only carry a single therapeutic agent. The complexity and escalating costs associated with the synthesis of more complex MNCs have been major technological roadblocks in the pathway for clinical translation. Here, we show that plasma polymerized nanoparticles (PPNs), synthesised in reactive gas discharges, can bind and effectively deliver multiple therapeutic cargo in a facile and cost-effective process compatible with up scaled commercial production. Delivery of siRNA against vascular endothelial growth factor (siVEGF) at extremely low concentrations (0.04 nM), significantly reduced VEGF expression in hard-to-transfect cells when compared with commercial platforms carrying higher siRNA doses (6.25 nM). PPNs carrying a combination of siVEGF and standard of care Paclitaxel (PPN-Dual) at reduced doses (< 100 µg/kg) synergistically modulated the microenvironment of orthotopic breast tumors in mice, and significantly reduced tumor growth. We propose PPNs as a new nanomaterial for delivery of therapeutics, which can be easily functionalised in any laboratory setting without the need for additional wet-chemistry and purification steps.

Predictors of Neoadjuvant Chemotherapy Response in Breast Cancer: A Review

Neoadjuvant chemotherapy (NAC) largely increases operative chances and improves prognosis of the local advanced breast cancer patients. However, no specific means have been invented to predict the therapy responses of patients receiving NAC. Therefore, we focus on the alterations of tumor tissue-related microenvironments such as stromal tumor-infiltrating lymphocytes status, cyclin-dependent kinase expression, non-coding RNA transcription or other small molecular changes, in order to detect potentially predicted biomarkers which reflect the therapeutic efficacy of NAC in different subtypes of breast cancer. Further, possible mechanisms are also discussed to discover feasible treatment targets. Thus, these findings will be helpful to promote the prognosis of breast cancer patients who received NAC and summarized in this review.

Characterizing Response to Neoadjuvant Chemotherapy in Invasive Lobular Breast Carcinoma

BACKGROUND

Pathological complete response (pCR) after neoadjuvant chemotherapy (NCT) for breast cancer is associated with improved survival and facilitates conservative surgical strategies. Invasive lobular carcinoma (ILC) has been observed to have decreased response to NCT compared with invasive ductal carcinoma (IDC). This study seeks to evaluate national trends in the use of NCT for ILC compared with IDC, and determine if there is a subset of ILC patients who demonstrate favorable response rates.

METHODS

This is a study using the National Cancer Database. The cohort consisted of patients with stage 1-3 ILC treated between 2010 and 2014, and a reference cohort of patient with IDC. For patients receiving NCT, pCR was assessed and clinically relevant variables were used in multivariable logistic regression models for each histologic subtype, modeling for pCR achievement. Survival analysis was performed for each histologic group to evaluate potential survival benefits of achieving pCR.

RESULTS

Our study cohort consisted of 384,887 women, of which 9.7% had ILC. A significantly lower rate of pCR after NCT was found in the cases of ILC compared with those of IDC (8.7% versus 23.2%). Increased response was seen in ILC patients with HER2-positive and TNBC subtypes. A survival benefit was demonstrated in patients with ILC who achieved pCR.

CONCLUSIONS

While response to NCT in patients with ILC is uncommon, our findings demonstrate a selective benefit for patients with HER2-positive tumors and TNBC. In addition, pCR is correlated with a clear survival advantage in ILC.

Protein Tyrosine Phosphatase 1B Inhibitors from the Stems of Akebia quinata

PTP1B deficiency in mouse mammary tumor virus (MMTV)-NeuNT transgenic mice inhibited the onset of MMTV-NeuNT-evoked breast cancer, while its overexpression was observed in breast cancer. Thus, PTP1B inhibitors are considered chemopreventative agents for breast cancer. As part of our program to find PTP1B inhibitors, one new diterpene glycoside (1) and 13 known compounds (2-14) were isolated from the methanol extract of the stems of Akebia quinata. All isolates were identified based on extensive spectroscopic data analysis, including UV, IR, NMR and MS. Compounds 2, 3, 6, 8 and 11 showed significant inhibitory effects on the PTP1B enzyme, with IC50 values ranging from 4.08 ± 1.09 to 21.80 ± 4.74 μM. PTP1B inhibitors also had concentration-dependent cytotoxic effects on breast cancer cell lines, such as MCF7, MDA-MB-231 and tamoxifen-resistant MCF7 (MCF7/TAMR) (IC50 values ranging from 0.84 ± 0.04 to 7.91 ± 0.39 μM). These results indicate that compounds 6 and 8 from Akebia quinata may be lead compounds acting as anti-breast cancer agents.