Human breast cancer: correlation of relapse and survival with amplification of the HER-2/neu oncogene

Mechanistic Regulation of Epidermal Growth Factor and Hormonal Receptors by Kinase Inhibitors and Organofluorines in Breast Cancer Therapy

Differential expression patterns of growth factor (EGFR, HER-2) and hormonal (ER, PR) receptors in breast cancer (BC) remain crucial for evaluating and tailoring therapeutic interventions. This study investigates differential expression profiles of hormonal and growth factor receptors in BC patients and across age groups, major subclasses, disease stages and tumor histology and survival rates, the efficacy of emerging clinical trial drugs (Dabrafenib and Palbociclib) and elucidating their molecular interaction mechanisms for efficient therapeutic strategies. Gene and protein expression analysis in the normal vs BC and across age groups and major subclasses reveals divergent patterns as EGFR and HER-2 levels are reduced in tumors versus normal tissue, while ER and PR levels are higher, particularly in luminal subtypes. However, there was no significant difference in survival rates among high and low/medium expression levels of EGFR and PR receptors. Conversely, patients with high HER-2 and ER expression exhibited poorer survival rates compared to low or medium expression levels. The in vitro findings indicate that Dabrafenib exhibits greater effectiveness than Palbociclib in suppressing various BC cells such as MCF-7 (Luminal), MDA-MB-231 (Triple-Negative), SKBR-3 (HER-2 + ) proliferation, promoting cell death, (IC50 of Dab < Pal) at 24 and 48 h, ROS production, and reduced ER and PR, elevated HER-2 with no change in EGFR expression. Molecular simulation studies revealed Dabrafenib's thermodynamically stable interactions (ΔG), tighter binding, and less structural deviation in the order EGFR > HER-2 > ER > PR as compared to Palbociclib (HER-2 > ER > PR = EGFR). These results indicate that Dabrafenib, compared to Palbociclib, more effectively regulates breast cancer cell proliferation through specific interactions with hormonal and growth factor receptors towards a repurposing approach.

Decoding mutational signatures in breast cancer: Insights from a multi-cohort study

PURPOSE

Diagnosis and treatment decisions of hormonal breast cancers (BC) are now guided by genomic mutations determination, combined into mutational signatures, and provide insight into the patients' genomic landscape. This work aims to compare genomic data and signatures extracted from tissue samples collected in the CICLADES study to existing cohorts. Ultimately, the goal is to prove the accuracy of smaller cohorts and provide new relevant data.

MATERIALS AND METHODS

DNA from patients of the CICLADES cohort was extracted, sequenced, and custom filtering was applied to the resulting files. Genomic data was pulled from 6 BC cohorts available on cBioPortal.com. In total, 2303 samples were analyzed. Mutational signatures were extracted and matched to known signatures of the Catalogue of Somatic Mutations in Cancer (COSMIC). Tumor Mutation Burden (TMB) and hypermutation were estimated and compared between samples.

RESULTS

PIK3CA and TP53 represented the two genes highly mutated across all cohorts. TMB was similar between the CICLADES and CBSM groups, however the MSKCC population showed a significantly higher TMB than both. Nine signatures were extracted, with recurring Single Base Substitutions (SBS) signatures like SBS1, SBS2 and SBS5. The presence of APOBEC-specific signatures was concordant with cohorts presenting APOBEC enrichment. The mean number of mutations was significantly higher in enriched samples for each analyzed cohort.

CONCLUSION

The use of comprehensive genomic profiling provided accurate evaluation of the TMB and extraction of signatures consistent with published literature. The genomic analysis of the tissue samples of the CICLADES cohort brings new and relevant data, comparable to results found in bigger cohorts.

Image analysis for bright-field HER2 in situ hybridization: validation for clinical use

The aim of the present study was to develop and validate a quantitative image analysis (IA) algorithm to aid pathologists in assessing bright-field HER2 in situ hybridization (ISH) tests in solid cancers. A cohort of 80 sequential cases (40 HER2-negative and 40 HER2-positive) were evaluated for HER2 gene amplification with bright-field ISH. We developed an IA algorithm using the ISH Module from HALO software to automatically quantify HER2 and CEP17 copy numbers per cell as well as the HER2/CEP17 ratio. We observed a high correlation of HER2/CEP17 ratio, an average of HER2 and CEP17 copy number per cell between visual and IA quantification (Pearson's correlation coefficient of 0.842, 0.916, and 0.765, respectively). IA was able to count from 124 cells to 47,044 cells (median of 5565 cells). The margin of error for the visual quantification of the HER2/CEP17 ratio and of the average of HER2 copy number per cell decreased from a median of 0.23 to 0.02 and from a median of 0.49 to 0.04, respectively, in IA. Curve estimation regression models showed that a minimum of 469 or 953 invasive cancer cells per case is needed to reach an average margin of error below 0.1 for the HER2/CEP17 ratio or for the average of HER2 copy number per cell, respectively. Lastly, on average, a case took 212.1 s to execute the IA, which means that it evaluates about 130 cells/s and requires 6.7 s/mm2. The concordance of the IA software with the visual scoring was 95%, with a sensitivity of 90% and a specificity of 100%. All four discordant cases were able to achieve concordant results after the region of interest adjustment. In conclusion, this validation study underscores the usefulness of IA in HER2 ISH testing, displaying excellent concordance with visual scoring and significantly reducing margins of error.

NK cell immunopotentiators-loaded nanoliposomes enhance ADCC effect for targeted therapy against HER2-positive breast cancer

Trastuzumab serves as a cornerstone of first-line therapy for HER2-positive (HER2+) breast cancer; however, a significant challenge arises due to the emergence of resistance within approximately one year of commencement of treatment, particularly in advanced cases with metastatic disease where its efficacy is limited. Our investigation into the tumor tissue from HER2+ breast cancer patients, employing single-cell sequencing and bioinformatics analysis, has elucidated a crucial mechanism underlying the reduced responsiveness of tumors to trastuzumab: the diminished infiltration and activity of natural killer (NK) cells within the tumor microenvironment (TME). To counteract this impediment, we meticulously selected two potent immune-modulating peptides TKD and IP-10p, which are known to recruit and enhance the activity of NK cells. Through in vitro experiments, we substantiated that bolstering the tumor infiltration and activity of NK cells can lead to an enhanced antibody-dependent cell-mediated cytotoxicity (ADCC) effect, thereby amplifying the anti-tumor activity of trastuzumab. Building upon this foundational discovery, we further designed HER2-targeted pH-sensitive nanoliposomes to encapsulate TKD and IP-10p peptides. The novel designed nanoliposomes were strategically employed in conjunction with NK cell supplement therapy within a HER2+ breast cancer model undergoing trastuzumab treatment, yielding a striking anti-tumor response and indicating that the combination strategy effectively reinvigorated the anti-tumor immune response. In essence, this study not only underscores a critical link between the diminished ADCC effect mediated by trastuzumab and the development of resistance in HER2+ breast cancer but also demonstrates leveraging HER2-targeted nanoliposomes to deliver NK cell immunopotentiators can significantly enhance the functional activity of NK cells and their infiltration within the TME, culminating in improved antitumor efficacy of trastuzumab through the augmentation of the ADCC effect.

STANCE: a unified statistical model to detect cell-type-specific spatially variable genes in spatial transcriptomics

One of the major challenges in spatial transcriptomics is to detect spatially variable genes (SVGs), whose expression patterns are non-random across tissue locations. Many SVGs correlate with cell type compositions, introducing the concept of cell type-specific SVGs (ctSVGs). Existing ctSVG detection methods treat cell type-specific spatial effects as fixed effects, leading to tissue spatial rotation-dependent results. Moreover, SVGs may exhibit random spatial patterns within cell types, meaning an SVG is not always a ctSVG, and vice versa, further complicating detection. We propose STANCE, a unified statistical model for both SVGs and ctSVGs detection under a linear mixed-effect model framework that integrates gene expression, spatial location, and cell type composition information. STANCE ensures tissue rotation-invariant results, with a two-stage approach: initial SVG/ctSVG detection followed by ctSVG-specific testing. We demonstrate its performance through extensive simulations and analyses of public datasets. Downstream analyses reveal STANCE's potential in spatial transcriptomics analysis.

Apolipoprotein Fusion Enables Spontaneous Functionalization of mRNA Lipid Nanoparticles with Antibody for Targeted Cancer Therapy

The mRNA-lipid nanoparticles (mRNA@LNPs) offer a novel opportunity to treat targets previously considered undruggable. Although antibody conjugation is crucial for enhancing the specificity, delivery efficiency, and minimizing the toxicity of mRNA therapeutics, current chemical conjugation methods are complex and produce heterogeneous particles with misoriented antibodies. In this work, we introduce a chemical-free approach to functionalize mRNA@LNPs with antibodies, mimicking protein corona formation for targeted mRNA delivery. By fusing apolipoprotein to the Fc domain of a targeting antibody, we enabled the antibody to spontaneously display on the surface of mRNA@LNPs without altering the existing LNP process or employing complex chemical conjugation techniques. We demonstrated precise protein expression using trastuzumab-bound mRNA@LNPs, facilitating specific mRNA expression in HER2-positive cancer cells. mRNA was efficiently delivered to the tumor site after intravenous administration. While the control LNPs lacking targeting antibodies caused acute liver toxicity, trastuzumab-displayed LNPs showed no systemic toxicity. The tumor-specific delivery of p53 tumor suppressor mRNA led to the complete regression of cancer cells. Thus, apolipoprotein fusion enables a straightforward and scalable production of antibody-functionalized mRNA@LNPs, offering significant therapeutic potential in gene therapy.

Cannabinoids as Promising Inhibitors of HER2-Tyrosine Kinase: A Novel Strategy for Targeting HER2-Positive Ovarian Cancer

Human epidermal growth factor receptor 2 (HER2) is a transmembrane receptor within the ErbB family that plays a pivotal role in the progression of various aggressive cancers. HER2-positive tumors often develop resistance to standard therapies, necessitating the exploration of innovative treatment options. Cannabinoids, bioactive compounds from Cannabis sativa such as cannabidiol (CBD), cannabigerol (CBG), and cannabinol (CBN), have gained attention for their potential anticancer properties. This study evaluates the efficacy of CBD, CBG, and CBN in targeting HER2-positive ovarian cancer through kinase inhibition assays, surface plasmon resonance (SPR), molecular docking, and cell viability assessments. SPR analysis revealed that cannabinoids bind strongly to HER2-tyrosine kinase (HER2-TK), with CBD showing the highest affinity (K D = 6.16 μM), significantly better than afatinib (K D = 26.30 μM), and CBG demonstrating moderate affinity (K D = 17.07 μM). In kinase inhibition assays, CBG was the most potent inhibitor (IC50 = 24.7 nM), followed by CBD (IC50 = 38 nM), suggesting their ability to disrupt HER2-mediated signaling pathways. Molecular docking studies highlighted critical interactions between cannabinoids and essential HER2 residues (Leu796, Thr862, Asp863). In cell viability assays, CBD and CBG effectively inhibited the growth of HER2-positive SKOV3 cells (IC50 = 13.8 μM and 16.6 μM, respectively), comparable to traditional tyrosine kinase inhibitors. These findings underscore the therapeutic potential of cannabinoids, particularly CBD and CBG, as alternative or adjunct therapies for HER2-positive cancers, with the promise of mitigating resistance and adverse effects associated with existing treatments.

Adaptive Proteomic Changes in Protein Metabolism and Mitochondrial Alterations Associated with Resistance to Trastuzumab and Pertuzumab Therapy in HER2-Positive Breast Cancer

HER2 (human epidermal growth factor receptor 2) is overexpressed in approximately 15-20% of breast cancers, leading to aggressive tumour growth and poor prognosis. Anti-HER2 therapies, such as trastuzumab and pertuzumab, have significantly improved the outcomes for patients with HER2-positive breast cancer by blocking HER2 signalling. However, intrinsic and acquired resistance remains a major clinical challenge, limiting the long-term effectiveness of these therapies. Understanding the mechanisms of resistance is essential for developing strategies to overcome it and improve the therapeutic outcomes. We generated multiple HER2-positive breast cancer cell line models resistant to trastuzumab and pertuzumab combination therapy. Using mass spectrometry-based proteomics, we conducted a comprehensive analysis to identify the mechanisms underlying resistance. Proteomic analysis identified 618 differentially expressed proteins, with a core of 83 overexpressed and 118 downregulated proteins. Through a series of advanced bioinformatics analyses, we identified significant protein alterations and signalling pathways potentially responsible for the development of resistance, revealing key alterations in the protein metabolism, mitochondrial function, and signalling pathways, such as MAPK, TNF, and TGFβ. These findings identify mitochondrial activity and detoxification processes as pivotal mechanisms underlying the resistance to anti-HER2 therapy. Additionally, we identified key proteins, including ANXA1, SLC2A1, and PPIG, which contribute to the tumour progression and resistance phenotype. Our study suggests that targeting these pathways and proteins could form the basis of novel therapeutic strategies to overcome resistance in HER2-positive breast cancer.

Six events that shaped antibody approvals in oncology

A little over twenty-five years ago, the European Medicines Agency (EMA) and the Food and Drug Administration (FDA) approved the chimeric antibody rituximab which fundamentally altered the landscape of anti-cancer drugs. While only a few antibodies were approved in the immediate years that followed the rituximab approval, the last decade saw a wave of antibody-drug approvals in the oncology arena. In the last three years, the EMA and FDA greenlighted eighteen antibodies, the majority of them designed in the formats of antibody-drug conjugates (ADC) and bispecific antibodies (BsAb). While the use of ADC and BsAb formats and the current rapid pace of approvals appear routine and almost inevitable, such progress was thought to be quite improbable in the early days of therapeutic antibody development. To understand how we arrived at the current state of antibody development in oncology, we focus on six monumental events that shaped antibody approvals over the last two and half decades. We examine the circumstances that led to the approval of rituximab and trastuzumab, the first successful antibodies for the treatment of hematologic and solid cancers. We detail the generation of the ADC and BsAb formats that dramatically augmented antibody-mediated precision cytotoxicity. Finally, we explore the development of ipilimumab, the first immune checkpoint-inhibiting antibody that activates the immune system to kill cancer cells, and the discovery that allowed the use of checkpoint inhibitors across all cancer types based on the presence of genetic markers. Revisiting these key events provides critical insights into the process of antibody development in oncology.

Next-generation sequencing based deep learning model for prediction of HER2 status and response to HER2-targeted neoadjuvant chemotherapy

INTRODUCTION

For patients with breast cancer, the amplification of Human Epidermal Growth Factor 2 (HER2) is closely related to their prognosis and treatment decisions. This study aimed to further improve the accuracy and efficiency of HER2 amplification status detection with a deep learning model, and apply the model to predict the efficacy of neoadjuvant therapy.

METHODS

We combined Next-Generation Sequencing (NGS) data and IHC staining images of 606 breast cancer patients and developed a Vision Transformer (ViT) deep learning model to identify the amplification of HER2 through these IHC staining images. This model was then applied to predict the efficacy of neoadjuvant therapy in 399 HER2-positive breast cancer patients.

RESULTS

The NGS data of 606 patients were split into training (N = 404), validation (N = 101), and testing (N = 101) sets. The top 3 genes with highest mutation frequency were TP53, ERBB2 and PIK3CA. With the NGS results as deep learning model labels, the accuracy of our ViT model was 93.1% for HER2 amplification recognition. The misidentifications was likely due to the heterogeneity of HER2 expression in cancer tissues. For predicting the efficacy of neoadjuvant therapy, receiver operating characteristic (ROC) curves were plotted, and the combination of image recognition result and clinical pathological features yielded an area under the curve (AUC) value of 0.855 in the training set and 0.841 in the testing set.

CONCLUSIONS

Our study provided a method of HER2 status recognition based on IHC images, improving the efficiency and accuracy of HER2 status assessment, and can be used for predicting the efficacy of anti-HER2 targeted neoadjuvant therapy. We intend our deep learning model to assist pathologists in HER2 amplification recognition.

HER-SAFE study design: an open-label, randomised controlled trial to investigate the safety of withdrawal of pharmacological treatment for recovered HER2-targeted therapy-related cardiac dysfunction

INTRODUCTION

A quarter of breast cancers show human epidermal growth factor-2 (HER2) overexpression, where targeted therapy dramatically improves survival. However, cancer therapy-related cardiac dysfunction (CTRCD) occurs in up to 15% of patients. With the interruption of HER2 therapy, if necessary, and the initiation of heart failure therapy (HFT), HER2 CTRCD recovers in over 80% of cases. The need to continue HFT in 'recovered' HER2 CTRCD following completion of HER2 therapy is unclear and there are potential significant impacts on patient's quality of life (QoL). The Randomised Controlled Trial for the Safety of Withdrawal of Pharmacological Treatment for Recovered HER2 Targeted Therapy Related Cardiac Dysfunction (HER-SAFE) aims to evaluate whether HFT can be safely withdrawn in non-high cardiovascular (CV) risk patients with 'recovered' HER2 CTRCD.

METHODS AND ANALYSIS

This is a multicentre, open-label randomised controlled trial investigating whether withdrawal of HFT is non-inferior to continuation in non-high CV risk, breast cancer survivors with recovered HER2 CTRCD after cancer treatment completion. The primary endpoint is the incidence of guideline-defined cardiac dysfunction or clinical heart failure. Secondary endpoints include changes in cardiac blood biomarkers, cardiovascular magnetic resonance (CMR)-derived strain and tissue mapping and heart failure symptom questionnaires. The study will recruit 90 participants who will undergo serial clinical assessment over 12 months with advanced cardiovascular imaging (CMR scans with automated analysis at baseline, 6 and 12 months), cardiac biomarker measurement (six time points over 12 months), plus complete heart failure QoL and medication disutility questionnaires. This is the first multicentre study to address this significant clinical issue.

ETHICS AND DISSEMINATION

This study was approved by the research ethics committee (London-London Bridge, 23/LO/0152). The results will be disseminated in peer-reviewed scientific journals.

TRIAL REGISTRATION NUMBER

NCT05880160.

Pooled clinical trial analyses evaluating outcomes of HER2-low vs HER2-0 expression in patients with metastatic breast cancer following chemotherapy

The therapeutic importance of subsetting patients with HER2-negative breast cancer according to their tumors' cellular HER2 expression (e.g., HER2-low vs. HER2-0) is relatively new, stemming from the dramatic results of the DESTINY-04 trial which established HER2-low expression as actionable. Most prior observational research of traditionally HER2-negative patients suggests that tumor behavior and biology do not vary according to HER2-low vs. HER2-0 expression, though some studies suggest otherwise. Here we studied this question in women with metastatic breast cancer (MBC) who were treated with standard single agent chemotherapy in the setting of clinical trials carried out in the pre-DESTINY-04 era. After pooling data from 142 female patients with MBC across historic clinical trials and categorizing them according to HER2 expression (i.e., HER2-0 or HER2-low), we evaluated associations between HER2 expression and the outcomes of both progression-free survival (PFS) and overall survival (OS) with both Kaplan-Meier and Cox proportional hazards methods. Studying data from an era when quantifying amounts of tumor HER2 expression in HER2-negative patients was neither standardized nor clinically actionable, we found no meaningful clinical differences in PFS or OS according to HER2-low vs. HER2-0 status, supporting prior findings of no biologic differences.

Serum HER2 as potential prognostic biomarker in primary breast cancer patients

Tissue expressed human epidermal growth factor receptor 2 (HER2) is an established parameter of breast cancer, and it is determined in routine clinical practice by histology. This study aims to assess the prognostic value of serum HER2 protein quantified using ELISA in 66 primary breast cancer patients. The median follow-up period was 94 months. Prognostic performance was assessed through receiver operating characteristic (ROC), Cox proportional hazards regression, and Kaplan-Meier analyses. There was a significant difference between serum HER2 levels of patients with and without recurrence. Prognostic associations were significant for age, grade, nodal status, follicle-stimulating hormone, oestradiol, and serum HER2. The cut-off point for serum HER2 levels was 6.0 ng/mL. Recurrence incidence was 29% in the serum HER2high subgroup, compared to only 10% in the serum HER2low subgroup. Serum HER2 testing by ELISA holds promise as an additional tool alongside routine tissue HER2 analysis for primary breast cancer patients.

Clinicopathological features and prognosis of breast cancer with low HER2 status evaluated by fluorescence in situ hybridization

Although trastuzumab deruxtecan improves the prognosis of patients with HER2-low breast cancer, the characteristics and prognostic value of low HER2 status remains to be elucidated. A prospective database of patients with clinical stage I to III breast cancer who underwent surgery between September 2012 and October 2022 at Teikyo University Hospital (Tokyo, Japan) were analyzed. HER2 was evaluated using fluorescence in situ hybridization assay, and HER2-low and HER2-negative was defined as HER2/CEP17 ratio ≥1.0, and <1.0, respectively. The median age and Ki67 score of the 1,024 patients were 56.0 years (range, 23.0-93.0 years) and 15.0% (range, 0.5-99.0%), respectively. Overall, 908 (88.7%) patients were hormone receptor positive. Among all patients, 902 (88.1%) had HER2-low tumors and 122 (11.9%) had HER2-negative tumors. Positive rates for estrogen receptor (ER) and progesterone receptor (PgR) were significantly higher in HER2-low compared with HER2-negative patients [ER: 804 (89.1%) patients vs. 99 (81.1%) patients, P=0.021; PgR: 723 (80.1%) patients vs. 86 (70.5%) patients, P=0.023]. The median Ki67 score was significantly lower in HER2-low compared with HER2-negative patients (14.5 vs. 18.5%; P=0.013). With a median follow-up time of 46.2 months, the overall survival (OS) was significantly improved in HER2-low compared with HER2-negative patients (97.4 vs. 96.7%; P=0.029). Multivariate logistic regression analyses revealed that HER2-low status was not an independent factor for OS. The findings of the present study suggest that HER2-low status may not have a significant association with prognosis, despite a significant association between Ki67 and hormone receptor expression.

A Clinical Review of Subcutaneous Trastuzumab and the Fixed-Dose Combination of Pertuzumab and Trastuzumab for Subcutaneous Injection in the Treatment of HER2-Positive Breast Cancer

Therapy directed against human epidermal growth factor receptor type 2 (HER2) is the standard of care for patients with early-stage and metastatic HER2-positive breast cancer. Treating patients with HER2-positive breast cancer with anti-HER2-monoclonal antibodies, specifically trastuzumab and pertuzumab, is considered standard of care in the neoadjuvant and adjuvant settings and in the first-line setting for metastatic HER2-positive breast cancer. Pertuzumab and trastuzumab are commonly administered intravenously. Subcutaneous (SC) formulations of trastuzumab alone and as a combined product of pertuzumab and trastuzumab are now available for clinical use. Phase III trial results demonstrate that the efficacy and safety of SC trastuzumab and fixed-dose combination of pertuzumab, trastuzumab, and hyaluronidase-zzxf for subcutaneous (PH FDC SC) injection and the intravenous (IV) formulation counterparts are comparable. SC formulations of anti-HER2 monoclonal antibodies offer several advantages over IV counterparts, including shorter administration time, less need for IV access, and better resource utilization for treatment facilities. This review summarizes the clinical data supporting the use of SC trastuzumab and PH FDC SC injection in treating early-stage and metastatic HER2-positive breast cancer and highlights the benefits of SC injection compared to the IV formulations.

Real-world neoadjuvant and adjuvant Trastuzumab-containing regimen patterns and their association with survival among patients with operable HER2-positive breast cancer from 2007 to 2021

PURPOSE

Chemotherapy in combination with trastuzumab is the standard neoadjuvant and adjuvant therapy for human epidermal growth factor receptor 2 (HER2)-positive breast cancer (BC). Assessing the regimens administered to patients with HER2-positive BC in the real world is lacking. We evaluated neoadjuvant and adjuvant regimen patterns among HER2-positive BC patients (2007 to 2021) identified in a health insurance claims database.

METHODS

Female BC patients ≥ 18 years who received chemotherapy, surgery, and trastuzumab were chosen from Optum's de-identified Clinformatics® Data Mart database. Summary statistics, Joinpoint models, Kaplan-Meier survival curves, and Cox regression models were used to analyze the data.

RESULTS

We identified 6474 patients (median age 60 years), 71.7% were White, 10.9% were Black, 8.6% were Hispanic, 4.1% were Asian, and 4.7% had unknown race/ethnicity. About 33.8% received neoadjuvant therapy and neoadjuvant therapy use increased with an annual percent change of 10.24% (P < .001). The three most common regimens were adjuvant docetaxel, carboplatin, and trastuzumab (TCH; 29.0%); adjuvant paclitaxel and trastuzumab (17.7%); and neoadjuvant TCH with pertuzumab followed by adjuvant trastuzumab (17.7%). The 5-year overall survival (OS) was 96% (95% CI, 95-96%). Patients had an increased risk of death if they were ≥ 59 years at diagnosis, had a health maintenance organization or other insurance plan, had dual Medicare/Medicaid eligibility, had a mastectomy, did not receive 18 cycles of trastuzumab, or received regimens not recommended by the National Comprehensive Cancer Network.

CONCLUSION

Treatment regimen patterns for HER2-positive BC evolved in correspondence with the U.S. Food and Drug Administration's approval of new drugs for this cancer and National Comprehensive Cancer Network treatment guidelines.

A multicenter retrospective study of early cardiac toxicity in operable breast cancer patients receiving concurrent dual or mono anti-HER2 therapy with postoperative radiation therapy

PURPOSE

This study aims to assess whether dual anti-HER2 therapy with trastuzumab and pertuzumab increases early cardiac toxicity compared to trastuzumab alone in breast cancer (BC) patients receiving postoperative radiation therapy (RT).

METHODS

Consecutive operable BC patients receiving postoperative RT and trastuzumab with or without pertuzumab between January 2017 and September 2020 at seven tertiary hospitals in China were retrospectively reviewed. Cardiac examinations included echocardiography, electrocardiogram (ECG), NT-proBNP, and cTnI at baseline before RT and during the follow-up. The cardiac event is any new-onset symptomatic heart disease or abnormality in the cardiac examination after RT.

RESULTS

In total, 681 patients were enrolled in the analysis, of whom 567 were treated with trastuzumab-alone and 124 patients received dual anti-HER2 therapy. The median follow-up was 11 months. Multivariate analysis showed that left-sided breast cancer (HR 2.38; 95%CI 1.65-3.44, p < 0.001) and IMN RT (HR 1.47; 95 % CI 1.01-2.15, P-value = 0.047) are independent risk factors for ECG abnormalities. Age >50 years is an independent risk factor for developing LVDD (HR 5.16; 95%CI 1.17-22.73, P-value = 0.030). Dosimetric analysis showed that patients who developed subclinical cardiac events had increased mean heart dose (412.0 ± 249.6 vs. 347.2 ± 242.6 cGy, P-value = 0.010). Among right-sided patients or patients receiving anthracycline-based chemotherapy, the dual-targeted cohort had a higher risk of developing ECG abnormalities compared to the trastuzumab-only cohort.

CONCLUSION

Compared with trastuzumab-only, dual anti-HER2 therapy does not increase early cardiac toxicity in combination with postoperative RT in BC patients. Cardiac radiation exposure remains the primary risk factor for early toxicity.

99mTc-HYNIC PEGylated Peptide Probe Targeting HER2-Expression in Breast Cancer

Increased HER2 expression during breast cancer and its metastatic spread can be checked by specific probes having high affinity towards the target. This study aimed at developing 99mTc-labelled HER2-specific molecular probe for accurate detection. The two rL-A9 peptide variants, HYNIC-rL-A9 and HYNIC-PEG12-rL-A9 were manually synthesized by solid phase methodology. 99mTc-labelling of peptides was accomplished using EDDA and tricine as co-ligands. [99mTc]Tc-HYNIC-rL-A9 showed poor uptake in HER2-expressing human breast carcinoma SKBR3 cells whereas the PEGylated counterpart [99mTc]Tc-HYNIC-PEG12-rL-A9 demonstrated high specific cellular uptake (3.01% ± 0.14%) and low nanomolar binding affinity (Kd = 17.11 ± 7.63 nM). Tumour uptake (SKBR3) of [99mTc]Tc-HYNIC-PEG12-rL-A9 was higher at 1 and 3 h in comparison to the non-PEGylated radiopeptide. Blocking studies led to 70% reduction in accumulation of radioactivity in the tumour indicating specificity of the radiopeptide. Introduction of polyethylene glycol (PEG12) as pharmacokinetic modifier led to significantly improved biological profile of the [99mTc]Tc-HYNIC-labelled rL-A9 peptide conjugate.

Outcomes and treatment patterns for stage I human epidermal growth factor receptor 2-positive breast cancer in the Surveillance, Epidemiology, and End Results database, 2010-2019

BACKGROUND

The risk of recurrence in patients with small, lymph node-negative, human epidermal growth factor receptor 2 (HER2)-positive breast cancers untreated with adjuvant chemotherapy/HER2-directed therapy is uncertain. To investigate this, the authors conducted a retrospective, population-based study of chemotherapy use and breast cancer-specific survival (BCSS) among patients with stage IA HER2-positive breast cancer.

METHODS

The authors analyzed Surveillance, Epidemiology, and End Results data from patients diagnosed with stage IA HER2-positive breast cancer from 2010 to 2019. They examined the frequency of chemotherapy use by tumor size and hormone receptor (HR) status and applied multivariate logistic regression to assess the factors associated with receipt of chemotherapy. BCSS was evaluated and performed multivariable Cox regression was performed to evaluate the association between chemotherapy receipt and BCSS.

RESULTS

Among 12,896 patients, 74.0% had HR-positive/HER2-positive breast cancer, and 26.0% had HR-negative/HER2-positive breast cancer. Adjuvant chemotherapy was received by to 58.9% of patients, with lower utilization for those who were older, Hispanic or Asian/Pacific Islander, separated/divorced/widowed, or had a lower median household income. The median follow-up was 46 months. Among the patients who had pathologic T1 (pT1) microscopic, pT1a, or pT1b tumors, the 5-year BCSS rate was 97.6%-99.6% in those who had no evidence of chemotherapy receipt in the medical record versus 98.4%-100.0% in those who did receive chemotherapy. Among patients who had pT1c tumors and had no evidence of chemotherapy receipt, the 5-year BCSS rate was 92.1% for those with HR-negative/HER2-positive breast cancer and 96.0% for those with HR-positive/HER2-positive breast cancer. Patients who had pT1c tumors and received chemotherapy had a 5-year BCSS rate of 96.7% in those with HR-negative/HER2-positive breast cancer and 98.7% in those with HR-positive/HER2-positive breast cancer.

CONCLUSIONS

In this large, population-based study of patients with stage IA HER2-positive breast cancer, patients who had tumors ≤1 cm had excellent outcomes with or without chemotherapy. Patients with pT1c tumors had a greater increase in BCSS with the receipt chemotherapy.

Synthesis and Anticancer Evaluation of O-Alkylated (E)-Chalcone Derivatives: A Focus on Estrogen Receptor Inhibition

Cancer remains a leading cause of morbidity and mortality worldwide, highlighting the urgent need for novel therapeutic agents. This study investigated the synthesis and biological evaluation of O-alkyl (E)-chalcone derivatives (4a-4v) as potential anticancer agents. The compounds were synthesized via aldol condensation of substituted aldehydes and acetophenones, with structures confirmed by IR, NMR, and mass spectrometry. In vitro cytotoxicity assays revealed varying effectiveness, with compounds 4a, 4b, 4q, and 4v exhibiting potent activity against MDA-MB-231 and MCF-7, showing IC50 values between 2.08 and 13.58 µM, besides HCT-116 and HeLa cancer cell lines (IC50 values between 6.59 and 22.64 µM). Notably, compound 4b displayed remarkable selectivity, with an IC50 of 54.59 µM against the non-cancerous WI-38 cell line. Additionally, protein kinase inhibition assays indicated that compounds 4b and 4q effectively inhibited EGFR and VEGFR-2, with 4b outperforming the standard inhibitor erlotinib. Molecular docking studies of compound 4q showed strong binding affinities in the ATP-binding pockets of EGFR, HER2, VEGFR2, and CDK2. In silico analyses further highlighted the favorable pharmacokinetic properties of compound 4q, underscoring its potential as a selective tyrosine kinase inhibitor. These findings suggest the therapeutic promise of O-alkyl (E)-chalcone derivatives in cancer treatment.

Methanolic Leaves Extract of Ziziphus spina-christi Inhibits Cell Proliferation and Migration of HER2-Positive Breast Cancer via p38 MAPK Signaling Pathway

Human epidermal growth factor receptor 2 (HER2) is a subtype of breast cancer that is associated with poor prognosis and low survival rates. The discovery of novel anti-cancer agents to manage this subtype of cancer is still needed. Ziziphus spina-christi (ZSC) is a plant species that is native to Qatar. It exerts various biological activities, including cytotoxicity as it contains different essential bioactive constituents, mainly rutin and quercetin. To examine the outcome of ZSC on HER2-positive breast cancer, we standardized the ZSC methanolic leaves extracted by Reverse Phase High-Performance Liquid Chromatography (RP-HPLC) analysis using the flavonoids rutin and quercetin as marker compounds. Here we used two HER2-positive breast cancer cell lines, ZR-75-1 and SK-BR-3, and the chorioallantoic membrane as an angiogenesis model. We found that ZSC extract significantly reduces viability, alters the normal morphological phenotype of HER2-positive breast cancer cells, and inhibits cell migration as well as colony formation; this is accompanied by deregulating different apoptotic markers such as Bax/Bcl-2 and NF-κB in both cell lines. Additionally, ZSC methanolic extract significantly represses the angiogenesis of the chorioallantoic membrane model. Moreover, the molecular pathway investigations pointed out that ZSC extract represses the activity of HER2 and p38 MAPK which could be the main pathways behind the effect of ZSC in HER2-positive cells. Collectively, our results support the potential role of ZSC in the management of HER2-positive breast cancer and form the basis for future investigations.

A signaling molecule from intratumor bacteria promotes trastuzumab resistance in breast cancer cells

Emerging evidence indicates that intratumor bacteria exist as an active and specific tumor component in many tumor types beyond digestive and respiratory tumors. However, the biological impact and responsible molecules of such local bacteria-tumor direct interaction on cancer therapeutic response remain poorly understood. Trastuzumab is among the most commonly used drugs targeting the receptor tyrosine-protein kinase erbB-2 (ErbB2) in breast cancer, but its resistance is inevitable, severely limiting its clinical effectiveness. Here, we demonstrate that the quorum-sensing signaling molecule N-(3-oxo-dodecanoyl) homoserine lactone (3oc), a chemical compound released by Pseudomonas aeruginosa (P. aeruginosa), one tumor-resident bacteria with a relative high abundance in breast cancer, promotes breast cancer cell resistance to trastuzumab. Mechanically, 3oc directly leads to spontaneous dimerization of the transforming growth factor β (TGF-β) type II serine/threonine kinase receptor on the cell membrane in a ligand-independent manner. The 3oc-induced TGF-β signaling subsequently triggers ErbB2 phosphorylation and its downstream target activation, overcoming the inhibition effect of trastuzumab on ErbB2. With specific real-time qPCR, fluorescence in situ hybridization imaging, and liquid chromatography ionization tandem mass spectrometry analyses of clinical samples, we confirmed that P. aeruginosa and its signaling molecule 3oc exist in breast cancer tissues and there is a clinical correlation between P. aeruginosa colonization and trastuzumab resistance. This work expands the biological functions of intratumor bacteria in cancer treatment responsiveness and provides a unique perspective for overcoming trastuzumab resistance.

Computational-aided rational mutation design of pertuzumab to overcome active HER2 mutation S310F through antibody-drug conjugates

Recurrent missense mutations in the human epidermal growth factor receptor 2 (HER2) have been identified across various human cancers. Among these mutations, the active S310F mutation in the HER2 extracellular domain stands out as not only oncogenic but also confers resistance to pertuzumab, an antibody drug widely used in clinical cancer therapy, by impeding its binding. In this study, we have successfully employed computational-aided rational design to undertake directed evolution of pertuzumab, resulting in the creation of an evolved pertuzumab variant named Ptz-SA. This variant, with only two mutations (T30S/D31A) located on its heavy chain, effectively reinstates binding to the mutated antigen, at the expense of a 35-fold reduction in binding affinity to HER2 (S310F) compared to the wild-type pair. Subsequently, Ptz-SA demonstrates potent killing capacity through antigen-dependent cytotoxicity. Moreover, upon engineering Ptz-SA into antibody-drug conjugates, such as Ptz-SA-MMAE, it manifests notable in vitro and in vivo antitumor efficacy by efficiently delivering cytotoxic payload into tumor cells expressing HER2 (S310F). Cryoelectron microscopy studies elucidate the molecular mechanism underlying the restored binding ability of Ptz-SA toward the S310F mutation. The steric hindrance induced by the S310F mutation is efficiently circumvented by the T30S and D31A mutations, which provides adequate space to accommodate the larger phenylalanine. Additionally, Ptz-SA also exhibits binding capacity to HER2 (S310Y), another mutation occurring at the S310 site of HER2 with high frequency. The computational-aided evolution of pertuzumab provides an alternative strategy for overcoming point mutation-mediated resistance to therapeutic antibodies.

Endocrine treatment mechanisms in triple-positive breast cancer: from targeted therapies to advances in precision medicine

Triple-positive breast cancer (TPBC), defined by the co-expression of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2), poses unique therapeutic challenges due to complex signaling interactions and resulting treatment resistance. This review summarizes key findings on the molecular mechanisms and cross-talk among ER, PR, and HER2 pathways, which drive tumor proliferation and resistance to conventional therapies. Current strategies in TPBC treatment, including endocrine and HER2-targeted therapies, are explored alongside emerging approaches such as immunotherapy and CRISPR/Cas9 gene editing. Additionally, we discuss the tumor microenvironment (TME) and its role in treatment resistance, highlighting promising avenues for intervention through combination therapies and predictive biomarkers. By addressing these interdependent pathways and optimizing therapeutic strategies, precision medicine holds significant potential for improving TPBC patient outcomes and advancing individualized cancer care.

Preclinical Comparison of [111In]In- and [225Ac]Ac-DOTA-Trastuzumab IgG, F(ab')2 and Fab for Theranostic SPECT/CT Imaging and α-Particle Radioimmunotherapy of HER2-Positive Human Breast Cancer

Radioimmunotherapy (RIT) with α-particle-emitting, 225Ac complexed to trastuzumab may offer an alternative treatment for patients who progress on HER2-targeted therapies. Moreover, RIT with [225Ac]Ac-DOTA-trastuzumab could be combined with SPECT/CT imaging with [111In]In-DOTA-trastuzumab in a theranostic approach. In this study, we compared DOTA-conjugated trastuzumab IgG, F(ab')2 or Fab complexed to 111In or 225Ac for SPECT/CT imaging and α-particle RIT of subcutaneous (s.c.) HER2-positive 164/8-1B/H2N.luc+ human BC tumors in NRG mice. SPECT/CT imaging and tumor and normal tissue uptake were compared in NRG or NOD-SCID mice coinjected i.v. with [111In]In-DOTA-trastuzumab IgG, F(ab')2 or Fab and [225Ac]Ac-DOTA-trastuzumab IgG, F(ab')2 or Fab. Radiation absorbed doses in the tumor and normal organs for [225Ac]Ac-DOTA-trastuzumab IgG, F(ab')2 or Fab were estimated based on the biodistribution of the [111In]In-DOTA-trastuzumab IgG, F(ab')2 or Fab. Normal tissue toxicity was assessed by hematology and blood biochemistry analyses and monitoring body weight in NRG mice injected i.v. with 2 and 4 kBq of [225Ac]Ac-DOTA-trastuzumab IgG, F(ab')2 or Fab separated by 8 d. RIT studies were performed in NRG mice with s.c. 164/8-1B/H2N.luc+ tumors injected i.v. with 2 kBq and 4 kBq of [225Ac]Ac-DOTA-trastuzumab IgG, F(ab')2 or Fab separated by 8 d or irrelevant [225Ac]Ac-DOTA-IgG1, two doses of unlabeled trastuzumab IgG or 0.9% NaCl. A tumor growth index (TGI) was plotted vs time (d) and Kaplan-Meier median survival estimated. [111In]In-DOTA-trastuzumab IgG or F(ab')2 exhibited 4.1-fold and 3.3-fold significantly greater tumor uptake at 2 d postinjection (p.i.) than Fab at 24 h p.i. However, spleen uptake at 2 d p.i. for [111In]In-DOTA-trastuzumab IgG was 3.3-fold significantly higher than F(ab')2 and 13.2-fold higher than Fab at 24 h p.i. [111In]In-DOTA-trastuzumab F(ab')2 and Fab exhibited higher kidney uptake than IgG. Tumors were imaged by SPECT/CT with [111In]In-DOTA-trastuzumab IgG and F(ab')2 but were not well-visualized with [111In]In-DOTA-trastuzumab Fab. The absorbed dose in the tumor was 2.2-fold greater for [225Ac]Ac-DOTA-trastuzumab F(ab')2 than IgG and 3.4-fold greater than Fab. Hematological toxicity was observed for [225Ac]Ac-DOTA-trastuzumab IgG but not for [225Ac]Ac-DOTA-trastuzumab F(ab')2 or Fab. No kidney or liver toxicity or decreased body weight was observed for any RIT agent. Tumor growth was significantly inhibited by [225Ac]Ac-DOTA-trastuzumab IgG, F(ab')2 or Fab but [225Ac]Ac-DOTA-trastuzumab F(ab')2 was most effective for increasing median survival (46 d vs 22 d for IgG and 29 d for Fab). We conclude that [111In]In- and [225Ac]Ac-DOTA-trastuzumab F(ab')2 exhibited superior properties for theranostic imaging and α-particle RIT of HER2-positive human BC xenografts in NRG mice.

Molecular mechanisms and therapeutic strategies in overcoming chemotherapy resistance in cancer

Cancer remains a leading cause of mortality globally and a major health burden, with chemotherapy often serving as the primary therapeutic option for patients with advanced-stage disease, partially compensating for the limitations of non-curative treatments. However, the emergence of chemotherapy resistance significantly limits its efficacy, posing a major clinical challenge. Moreover, heterogeneity of resistance mechanisms across cancer types complicates the development of universally effective diagnostic and therapeutic approaches. Understanding the molecular mechanisms of chemoresistance and identifying strategies to overcome it are current research focal points. This review provides a comprehensive analysis of the key molecular mechanisms underlying chemotherapy resistance, including drug efflux, enhanced DNA damage repair (DDR), apoptosis evasion, epigenetic modifications, altered intracellular drug metabolism, and the role of cancer stem cells (CSCs). We also examine specific causes of resistance in major cancer types and highlight various molecular targets involved in resistance. Finally, we discuss current strategies aiming at overcoming chemotherapy resistance, such as combination therapies, targeted treatments, and novel drug delivery systems, while proposing future directions for research in this evolving field. By addressing these molecular barriers, this review lays a foundation for the development of more effective cancer therapies aimed at mitigating chemotherapy resistance.

Therapeutic potential of anti-ErbB3 chimeric antigen receptor natural killer cells against breast cancer

ErbB3 is markedly overexpressed in breast cancer cells and is associated with resistance and metastasis. Additionally, ErbB3 expression levels are positively correlated with low densities of tumor-infiltrating lymphocytes, a marker of poor prognosis. Consequently, ErbB3 is a promising therapeutic target for cancer immunotherapy. Here, we report the generation of ErbB3-targeted chimeric antigen receptor (CAR)-modified natural killer (NK) cells by transducing cord blood-derived primary NK cells using vsv-g envelope-pseudotyped lentiviral vectors. Transduced cells displayed stable CAR-expressing activity and increased cytotoxicity against ErbB3-positive breast cancer cell lines. Furthermore, anti-ErbB3 (aErbB3) CAR-NK cells strongly reduced the tumor burden in the SK-BR-3 xenograft mouse model without observable side effects. These findings underscore the potential of aErbB3 CAR-NK cells as targeted immunotherapy for ErbB3-positive breast cancer, suggesting a promising alternative to conventional treatments.

Right ventricular strain as a predictor of trastuzumab-induced chemotherapy-related cardiac dysfunction: A meta-analysis

INTRODUCTION

The survival rates of breast cancer patients have improved drastically in the past few decades due to advancements in anti-neoplastic drugs. Trastuzumab (TZ) chemotherapy is associated with left ventricular dysfunction leading to cardiotoxicity. Two-dimensional speckle-tracking echocardiography has demonstrated efficacy in predicting TZ-induced cardiotoxicity; however, its role in using right ventricular (RV) strain parameters remains unclear.

METHODS

A comprehensive literature search spanning major electronic databases was conducted to identify studies comparing pre- and post-TZ chemotherapy RV strain parameters. The outcomes of interest included RV global longitudinal strain (GLS) and RV free-wall longitudinal strain (FWLS). Mean differences (MD) with 95% confidence intervals (CI) were pooled using the inverse-variance random-effects model. Statistical significance was set at p<0.05.

RESULTS

Four studies involving 275 cancer patients were included. The mean age of the patients was 53.35 ± 11.1 years. The pooled analysis demonstrated significantly reduced RV GLS [MD: -1.94; 95% CI: -2.83, -1.05; p<0.01] and RV FWLS [MD: -2.05; 95% CI: -3.61, -0.50; p<0.01] on follow-up post-TZ chemotherapy compared to pre-TZ baseline values.

CONCLUSION

Following TZ-based chemotherapy, RV subclinical damage ensues without overt clinical signs, leading to the deformation of RV mechanics. This meta-analysis demonstrated a reduction in RV GLS and RV FWLS after TZ-based chemotherapy.

LL-37, the master antimicrobial peptide, its multifaceted role from combating infections to cancer immunity

Antimicrobial peptides (AMPs) represent a unique group of naturally occurring molecules having diverse biological activities, including potent antimicrobial properties. Among them, LL-37 has emerged as a significant player, demonstrating its multifaceted roles during bacterial, fungal, and viral infections, as well as exhibiting intriguing implications in cancer. This review delves into the versatile functions of LL-37, elucidating its mechanisms of action against microbial pathogens and its potential to modulate immune responses. We explored the efficacy of LL-37 in disrupting bacterial membranes, inhibiting fungal growth, and interfering with viral replication, highlighting its potential as a therapeutic agent against a wide array of infectious diseases. Furthermore, we discussed the emerging role of LL-37 in cancer immunity, where its immunomodulatory effects and direct cytotoxicity towards cancer cells offer novel avenues for cancer therapy in the near future. We provided a comprehensive overview of the activities of LL-37 across various diseases and underscored the importance of further research into harnessing the therapeutic potential of this potential antimicrobial peptide along with other suitable candidates.

Ferroptosis-targeting drugs in breast cancer

In 2020, breast cancer surpassed lung cancer as the most common cancer in the world for the first time. Due to the resistance of some breast cancer cell lines to apoptosis, the therapeutic effect of anti-breast cancer drugs is limited. According to recent report, the susceptibility of breast cancer cells to ferroptosis affects the progress, prognosis and drug resistance of breast cancer. For instance, roblitinib induces ferroptosis of trastuzumab-resistant human epidermal growth factor receptor 2 (HER2)-positive breast cancer cells by diminishing fibroblast growth factor receptor 4 (FGFR4) expression, thereby augmenting the susceptibility of these cells to HER2-targeted therapies. In tamoxifen-resistant breast cancer cells, Fascin exacerbates their resistance by repressing solute carrier family 7 member 11 (SLC7A11) expression, which in turn heightens their responsiveness to tamoxifen. In recent years, Chinese herbs extracts and therapeutic drugs have been demonstrated to elicit ferroptosis in breast cancer cells by modulating a spectrum of regulatory factors pertinent to ferroptosis, including SLC7A11, glutathione peroxidase 4 (GPX4), acyl-CoA synthetase long chain family member 4 (ACSL4), and haem oxygenase 1 (HO-1). Here, we review the roles and mechanisms of Chinese herbal extracts and therapeutic drugs in regulating ferroptosis in breast cancer, providing potential therapeutic options for anti-breast cancer.

Switching to a Fixed-dose Combined Pertuzumab and Trastuzumab With Recombinant Human Hyaluronidase Subcutaneous Injection to Treat Human Epidermal Growth Factor Receptor 2-positive Breast Cancer in Real-world UK Clinical Practice

Current standard of care for human epidermal growth factor receptor 2 (HER2)-positive breast cancer is first-line treatment with chemotherapy in combination with the HER2-targeting monoclonal antibodies, trastuzumab and pertuzumab. While this treatment approach is associated with improved clinical outcomes, there is a treatment burden associated with the invasive and time-consuming nature of separate intravenous (IV) administration of pertuzumab and trastuzumab. In 2020, a novel subcutaneous (SC) formulation of pertuzumab plus trastuzumab with recombinant human hyaluronidase, available as a fixed-dose combination vial that can be administered in 5-8 minutes, was approved for use by the US Food and Drug Administration and the European Medicines Agency.

AIM

A UK cancer centre set out to switch all patients currently receiving IV infusion of pertuzumab and trastuzumab over to the combined SC injection in a safe and timely manner and to initiate all future patients on the combined SC injection.

MATERIALS AND METHODS

Organisational governance approval was obtained before a novel project model approach was used to implement the treatment switch which incorporated aspects such as education and multidisciplinary team collaboration.

RESULTS

Of the 97 eligible patients, 99% were switched to the combined SC injection safely and effectively over a 4-week period. Between 1st April 2021 and 30th September 2022, 3062 hours of pharmacy aseptic preparation time and 6764 hours of day unit chair time were saved. The number of aseptic unit operation days above the maximum capacity was reduced post-switch.

CONCLUSION

This initiative demonstrated the ability to rapidly and effectively transition >95% of eligible breast cancer patients from separate IV trastuzumab and pertuzumab to a fixed combined SC formulation. Patient benefits included shorter administration appointments and a less invasive form of treatment, whereas healthcare system benefits included substantial savings in aseptic preparation time and chair time, and a meaningful increase in clinic capacity. The reported treatment-switch process provides a model that can be adopted by other centres wishing to implement similar treatment switches.

ErbB2-NOTCH1 axis controls autophagy in cardiac cells

Although the epidermal growth factor receptor 2 (ErbB2) and Notch1 signaling pathways have both significant roles in regulating cardiac biology, their interplay in the heart remains poorly investigated. Here, we present evidence of a crosstalk between ErbB2 and Notch1 in cardiac cells, with effects on autophagy and proliferation. Overexpression of ErbB2 in H9c2 cardiomyoblasts induced Notch1 activation in a post-transcriptional, p38-dependent manner, while ErbB2 inhibition with the specific inhibitor, lapatinib, reduced Notch1 activation. Moreover, incubation of H9c2 cells with lapatinib resulted in stalled autophagic flux and decreased proliferation, consistent with the established cardiotoxicity of this and other ErbB2-targeting drugs. Confirming the findings in H9c2 cells, exposure of primary neonatal mouse cardiomyocytes to exogenous neuregulin-1, which engages ErbB2, stimulated proliferation, and this effect was abrogated by concomitant inhibition of the enzyme responsible for Notch1 activation. Furthermore, the hearts of transgenic mice specifically overexpressing ErbB2 in cardiomyocytes had increased levels of active Notch1 and of Notch-related genes. These data expand the knowledge of ErbB2 and Notch1 functions in the heart and may allow better understanding the mechanisms of the cardiotoxicity of ErbB2-targeting cancer treatments.

Envisioning Clinical Management of Breast Cancer: a Comprehensive Review

BACKGROUND

Background: Coming to the edge of disease manufacturing in the twenty-- first-century, breast cancer occupies a terrifying scenario in the globe, especially in adult women. Its curiosity endeavours remarkable advances made during the past decennaries for cancer treatment and diagnosis.

OBJECTIVE

It accounts for the fifth leading cause of transience, killing approximately 570,000 people per annum. To reduce the prognosis of clinical oncological development with the application of a new chemical entity, some of the critical challenges, like active pharmaceutical ingredients with high chemical resistance, extreme side effects, and high treatment costs are some of the limitations in the curbing aspects of breast melanoma.

METHODS

In cancer research, hence, the development of drugs that are safe, efficient, and cost-effective remains a 'Holy Grail' that may be considered as a boon to target the malignant tissues with novel therapeutics devices.

RESULTS

Through the findings on overcoming the drawbacks of traditional methods, researchers have given special attention to cancer-preventive and theranostic approaches based on some novel drug delivery systems.

CONCLUSION

The present study forecasts the wide-ranging modern applications, and on developing some novel liposomal drug delivery therapy against breast cancer.

The association of BMI and subclinical myocardial dysfunction in breast cancer patients after single or dual anti-HER2 targeted therapy

BACKGROUND

Anti-HER2 targeted therapy has significantly reduced the recurrence and death of HER2-overexpressing breast cancer patients, but might lead to cardiotoxicity. Some patients with normal myocardial function may suffer from subclinical myocardial dysfunction after anti-HER2 targeted therapy. We sought to evaluate earlier the subclinical myocardial dysfunction in breast cancer patients after single or dual anti-HER2 targeted therapy, and identify the risk factors related to subclinical myocardiotoxicity.

METHODS

In our study, 40 breast cancer patients after single anti-HER2 targeted therapy, and 40 breast cancer patients after dual anti-HER2 targeted therapy were enrolled. Global longitudinal strain (GLS) was measured through echocardiography.

RESULTS

Seven patients in single anti-HER2 therapy group and eight patients in dual anti-HER2 therapy group had GLS lower than - 18%, suggesting subclinical myocardial dysfunction, but no difference between these two groups. Furthermore, we found that increased BMI was associated with reduction of GLS in breast cancer patients after anti-HER2 targeted therapy. Increased BMI (OR 2.683; 95% CI 1.225-5.879) was a risk factor of subclinical cardiotoxicity in dual anti-HER2 targeted therapy group. In addition, the patients with BMI ≥ 25 were more prone to have subclinical myocardial dysfunction in dual anti-HER2 therapy group compared with those with BMI ≥ 25 in single anti-HER2 therapy group.

CONCLUSION

Our results indicate dual anti-HER2 therapy does not increase the risk of subclinical myocardial dysfunction for breast cancer patients, compared with single anti-HER2 therapy. Patients with BMI ≥ 25 are more prone to have subclinical cardiotoxicity after dual anti-HER2 therapy than after single anti-HER2 therapy. Weight reduction should be the major measure to prevent subclinical myocardial dysfunction for these patients.

The relationship between HER2 status acquired from pathological data and metabolic parameters from pre-treatment [18F]FDG PET/CT in gastric adenocarcinomas

OBJECTIVE

Overexpression of Human Epidermal Growth Factor Receptor 2 (HER2) is thought to be more aggressive in gastric cancer. This study aimed to evaluate the predictability of HER2 status and other prognostic pathologic parameters using [18F]FDG PET/CT and to investigate its impact on survival.

METHODS

Pretreatment metabolic parameters measured by [18F]FDG PET/CT as a prognostic factor were retrospectively evaluated in 117 HER2-analysed patients. The relationship between pathological data, tumor metabolic characteristics, and distant metastases was examined, and the effect on survival was investigated.

RESULTS

Among the 117 patients, 17.1% were HER2-positive (HER2+), and 82.9% were HER2-negative (HER2-). There was no significant association between PET/CT parameters in the HER2+ and HER2- patient groups. HER2+ patients had higher 1- and 3-year survival expectations than HER2- patients (80%-%37.9; %47.5-%20; respectively). There was no statistically significant difference in overall survival. In Cox-regression analysis, while the presence of vascular invasion, local invasion, and distant metastasis were poor prognostic factors, HER2 was not a prognostic factor. Vascular invasion and local invasion (T3/T4) were also associated with higher SUVmax values. Patients with distant metastases had significantly higher SUVmax, SUVmean, and TLG.

CONCLUSION

This study showed no association between HER2 expression and [18F]FDG PET/CT metabolic parameters. However, regardless of HER2 status, the results indicated distant metastasis, local invasion, and vascular invasion could be associated with primary tumor metabolism. PET/CT parameters predict tumor aggressiveness and disease prognosis better than HER2 status.

Evaluating the Anticancer Properties of Novel Piscidinol A Derivatives: Insights from DFT, Molecular Docking, and Molecular Dynamics Studies

Cancer is characterized by uncontrolled cell growth and spreading throughout the body. This study employed computational approaches to investigate 18 naturally derived anticancer piscidinol A derivatives (1-18) as potential therapeutics. By examining their interactions with 15 essential target proteins (HIF-1α, RanGAP, FOXM1, PARP2, HER2, ERα, NGF, FAS, GRP78, PRDX2, SCF complex, EGFR, Bcl-xL, ERG, and HSP70) and comparing them with established drugs such as camptothecin, docetaxel, etoposide, irinotecan, paclitaxel, and teniposide, compound 10 emerged as noteworthy. In molecular dynamics simulations, the protein with the strongest binding to the crucial 1A52 protein exceeded druglikeness criteria and displayed extraordinary stability within the enzyme's pocket over varied temperatures (300-320 K). Additionally, density functional theory was used to calculate dipole moments and molecular orbital characteristics, as well as analyze the thermodynamic stability of the putative anticancer derivatives. This finding reveals a well-defined, potentially therapeutic relationship supported by theoretical analysis, which is in good agreement with subsequent assessments of their potential in vitro cytotoxic effects of piscidinol A derivatives (6-18) against various cancer cell lines. Future in vivo and clinical studies are required to validate these findings further. Compound 10 thus emerges as an intriguing contender in the fight against cancer.

The Clinical Study of Intratumoral and Peritumoral Radiomics Based on DCE-MRI for HER-2 Positive and Low Expression Prediction in Breast Cancer

Background

Core biopsy sampling may not fully capture tumor heterogeneity. Radiomics provides a non-invasive method to assess tumor characteristics, including both the core and surrounding tissue, with the potential to improve the accuracy of HER-2 status prediction.

Objective

To explore the clinical value of intratumoral and peritumoral radiomics features from dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) for preoperative prediction of human epidermal growth factor receptor-2 (HER-2) expression status in breast cancer.

Methods

Two tasks were designed, including Task1-distinguished HER-2 positive and HER-2 negative from 382 breast cancer patients and Task2-distinguished HER-2 low and HER-2 zero expression from 249 patients with HER-2 negative. Three radiomics models (intratumoral, peritumoral 5 mm, intratumoral+peritumoral 5 mm) were constructed based on decision tree, and clinical combined radiomics models were constructed with logistic regression based on clinicopathological features and radscore. The area under the curve (AUC), sensitivity, specificity, accuracy and decision curve analysis (DCA) were used to evaluate the predictive performance of models.

Results

Estrogen receptor (ER), progesterone receptor (PR) and Ki67 showed statistically significant in the different groups of HER-2 expression. Additionally, magnetic resonance imaging-reported axillary lymph nodes (MRI-reported ALN) in the positive and negative groups and histological grade in the low and zero expression groups showed significant differences (all P < 0.05). For task 1, the peritumoral radiomics model outperformed the other two radiomics models, with AUC values of 0.774 and 0.727 in the training and testing sets, respectively. For task 2, intratumoral + peritumoral radiomics model in the testing set showed the best predictive performance among the three radiomics models, and the AUC values were 0.777. The addition of clinicopathological features slightly altered the AUC values in both tasks.

Conclusion

Both radiomics methods based on DCE-MRI and the nomogram are helpful for preoperative prediction of HER-2 expression status.

Genomic landscape of circulating tumor DNA in HER2-low metastatic breast cancer

The large population of HER2-low breast cancer patients necessitates further research to provide enhanced clinical guidance. In this study, we retrospectively analyzed 1071 metastatic breast cancer (MBC) patients and the circulating tumor DNA (ctDNA) to investigate clinicopathological and genetic alterations of HER2-low MBC patients. The effect of HER2-low status on different treatment modalities was explored in two prospective clinical trials (NCT03412383, NCT01917279) and a retrospective study. Our findings suggest TP53, PIK3CA, and ESR1 are frequently mutated genes in HER2-low MBC. Compared to the HER2-0 group, mutations observed in the HER2-low group are more closely associated with metabolic pathway alterations. Additionally, among patients with ERBB2 mutations and treated with pyrotinib, the HER2-low group may experience superior prognosis when compared to the HER2-0 group. Notably, we did not find any statistically significant disparity in the response to chemotherapy, endocrine therapy, or CDK4/6 inhibitor therapy between HER2-0 and HER2-low breast cancer patients. Interestingly, within the subgroup of individuals with metabolic pathway-related gene mutations, we found that HER2-low group exhibited a more favorable response to these treatments compared to HER2-0 group. Additionally, dynamic analysis showed the HER2-low MBC patients whose molecular tumor burden index decreased or achieved early clearance of ctDNA after the initial two treatment cycles, exhibited prolonged survival. Moreover, we classified HER2-low MBC into three clusters, providing a reference for subsequent treatment with enhanced precision. Our study offers valuable insights into the biology of HER2-low MBC and may provide reference for personalized treatment strategies.

A trafficking regulatory subnetwork governs αVβ6 integrin-HER2 cross-talk to control breast cancer invasion and drug resistance

HER2 and αVβ6 integrin are independent predictors of breast cancer survival and metastasis. We identify an αVβ6/HER2 cross-talk mechanism driving invasion, which is dysregulated in drug-resistant HER2+ breast cancer cells. Proteomic analyses reveal ligand-bound αVβ6 recruits HER2 and a trafficking subnetwork, comprising guanosine triphosphatases RAB5 and RAB7A and the Rab regulator guanine nucleotide dissociation inhibitor 2 (GDI2). The RAB5/RAB7A/GDI2 functional module mediates direct cross-talk between αVβ6 and HER2, affecting receptor trafficking and signaling. Acute exposure to trastuzumab increases recruitment of the subnetwork to αVβ6, but trastuzumab resistance decouples GDI2 recruitment. GDI2, RAB5, and RAB7A cooperate to regulate migration and transforming growth factor-β activation to promote invasion. However, these mechanisms are dysregulated in trastuzumab-resistant cells. In patients, RAB5A, RAB7A, and GDI2 expression correlates with patient survival and αVβ6 expression predicts relapse following trastuzumab treatment. Thus, the RAB5/RAB7A/GDI2 subnetwork regulates αVβ6-HER2 cross-talk to drive breast cancer invasion but is subverted in trastuzumab-resistant cells to drive αVβ6-independent and HER2-independent tumor progression.

HER2-Positive Serous Endometrial Cancer Treatment: Current Clinical Practice and Future Directions

The most common histological subtypes of endometrial cancer consist of endometrioid and uterine serous carcinoma, with the latter being more aggressive and accompanied by poor prognosis. Human epidermal growth factor receptor 2 (HER2) is a transmembrane tyrosine kinase receptor associated with cell proliferation, differentiation, and survival. HER2 positivity can be diagnosed in many solid tumors. It has been found that approximately one-third of the patients diagnosed with serous carcinoma may overexpress HER2/neu protein and/or show the amplification of the c-erBb2 gene. The prognostic and predictive value of HER2 biomarker is nowadays highlighted and the updates of HER2-directed treatment offer new opportunities for improved efficacy and survival. A number of HER2-targeted therapies have become available in recent years and have had promising results, prompting full drug approvals and additional investigation in many cancer types, among which is endometrial cancer. Data from clinical trials combining classical chemotherapy with anti-HER2 agents, mainly trastuzumab, alone or in combination with pertuzumab, do exist and have been incorporated into international guidelines. Moreover, further research with antibody-drug conjugates and tyrosine kinase inhibitors is being conducted. Acquired resistance remains an important problem, and its underlying mechanisms in endometrial cancer are mostly unknown. Studies exploring earlier use of Her2-directed therapy are also on the way. The purpose of this literature review is to describe the available therapies in the current clinical practice and the most prominent research data regarding the future. In any case, a number of unmet medical needs do exist for HER2-positive serous endometrial cancer, and additional research and studies are warranted to provide further understanding and improved outcomes for this tumor type.

Molecular Biology of Cancer-Interplay of Malignant Cells with Emerging Therapies

Cancer is currently one of the leading causes of death worldwide, and according to data from the World Health Organization reported in 2020, it ranks as the second leading cause of death globally, accounting for 10 million fatalities [...].

[64Cu]Cu-NOTA-Trastuzumab and [89Zr]Zr-DFO-Trastuzumab in Xenografts with Varied HER2 Expression

Positron emission tomography (PET) has potential as a complementary technique to biomarker analysis, especially for human epidermal growth factor receptor 2 (HER2)-expressing tumors characterized by high heterogeneity. In this study, zirconium-89 (89Zr) and copper-64 (64Cu) labeled trastuzumab were employed to monitor varying levels of tumoral HER2 expression. Additionally, we studied the use of the cholesterol-depleting lovastatin as a pharmacological approach to enhance cell-surface HER2 expression in tumors with moderate to low HER2 levels, aiming to increase antibody accumulation in these tumor types. Both 89Zr- and 64Cu-labeled trastuzumab effectively monitor HER2 expression levels in xenografts exhibiting varying HER2 expression. No significant difference in tumor uptake was observed between 89Zr- or 64Cu-labeled trastuzumab, and tumor uptake for both radioimmunoconjugates positively correlated with HER2 protein levels. These findings underscore the potential of PET to monitor HER2 protein levels across heterogeneous tumors. Furthermore, our results suggest that further optimization of statin dosing and timing could offer a promising strategy to enhance trastuzumab accumulation in HER2-high, HER2-moderate, and HER2-low tumors.

Real-World Prevalence, Treatment Patterns, and Outcomes for Patients With HER2 (ERBB2)-Mutant Metastatic Non-Small Cell Lung Cancer, From a US-Based Clinico-Genomic Database

OBJECTIVES

Targeted therapies have been shown to improve outcomes in metastatic non-small cell lung cancer (mNSCLC) with driver mutations. We evaluated the real-world prevalence of human epidermal growth factor receptor 2 (HER2; ERBB2) tumor gene mutations among patients with mNSCLC and described historical treatments and outcomes in patients with HER2-mutant mNSCLC, during a period when there was no approved targeted therapy for HER2-mutant mNSCLC.

MATERIALS AND METHODS

This retrospective observational study used a US nationwide de-identified NSCLC clinico-genomic database. Eligible patients were adults diagnosed with HER2-mutant mNSCLC from January 2014 to July 2021 without co-occuring epidermal growth factor receptor (EGFR) tumor mutations. Descriptive statistics were used to summarize prevalence, baseline characteristics and treatment patterns. Clinical outcomes were estimated with Kaplan-Meier analyses.

RESULTS

Among 9206 patients with mNSCLC, 164 (1.78%) met the eligibility criteria (mean age: 67.3 years, 63.4% White, 56.7% female, and 53.0% with a smoking history). 132/164 (80.5%) had at least one line of treatment. Platinum-based chemotherapy (45.5%) and immune checkpoint inhibitor (ICI) with chemotherapy (28.0%) were the most frequently used first-line treatments. The median (95% confidence interval [CI]) real-world (rw) progression-free survival in first-line was 5.5 (4.8, 6.2) months and 3.0 (2.3, 4.2) months in second-line. The median rw overall survival in first-line was 13.2 (10.6, 18.4) months and 8.2 (6.6, 13.2) months in second-line.

CONCLUSION

During this study period, the most common regimens were platinum-based chemotherapy with or without ICI in first and second line, and median rwOS was 13.2 and 8.2 months, respectively. These results indicate the need for more effective targeted therapies in this patient population.

Cardiovascular Considerations During Cancer Therapy: Gaps in Evidence and JACC: CardioOncology Expert Panel Recommendations

The administration of certain cancer therapies can be associated with the development of cardiovascular toxicity or complications. This spectrum of toxicities is broad and requires nuanced approaches for prevention, identification, and management. This expert panel summarizes the consensus of opinions of diverse health care professionals in several key areas: 1) cardioprotection involves strategies aimed at the primary prevention of cancer therapy-related cardiovascular toxicity; 2) surveillance entails monitoring for cancer therapy-related cardiovascular toxicity during cancer therapy; 3) permissive cardiotoxicity is the informed continuation of cancer therapy in the presence of cardiovascular toxicity, along with the implementation of mitigating cardiovascular treatments; and 4) special considerations include the invasive management of severe cardiovascular disease in patients receiving treatments for advanced cancer and the exploration of drug-drug interactions in cardio-oncology. In this expert panel, we also highlight gaps in evidence in an effort to continue to advance science in the cardiovascular care of our patients undergoing cancer therapy.

Cost-Effectiveness Analysis of Adjuvant Pertuzumab and Trastuzumab in Human Epidermal Growth Factor Receptor 2-Positive Early Breast Cancer in Japan

BACKGROUND AND OBJECTIVE

Human epidermal growth factor receptor 2 (HER2)-positive breast cancer presents considerable treatment challenges owing to its aggressive nature. Global guidelines have endorsed a full year of HER2-targeted therapy for early-stage breast cancer. However, previous cost-effectiveness analyses of dual HER2-targeted therapies have been limited. This study aimed to examine the cost effectiveness of dual HER2-targeted therapy for early-stage breast cancer within the Japanese healthcare system context.

METHODS

In the Markov model-based study, the cost effectiveness of dual anti-HER2 therapy, combining pertuzumab and trastuzumab, was assessed in comparison to trastuzumab monotherapy. Patients in whom treatment was initiated at a median age of 51 years were included. The study utilized quality-adjusted life years (QALYs) and incremental cost-effectiveness ratios (ICERs) as comparison units. Subgroup analyses were conducted to explore variations in cost effectiveness, focusing on node-positive and node-negative patients. Both one-way deterministic and broader probabilistic sensitivity analyses using Monte Carlo simulations with 10,000 samples were performed from the Japanese healthcare payers perspective.

RESULTS

Dual HER2-targeted therapy led to 0.17 QALYs increment at an additional cost of $US15,289, resulting in an ICER of $US92,232 per QALY. In the subgroup of node-positive patients, the benefit of the dual HER2-targeted therapy was more pronounced, with an increase of 0.64 QALYs and an ICER of $US24,561 per QALY. Sensitivity analyses revealed the model's susceptibility to changes in the transition probabilities from invasive disease-free survival to death, from invasive disease-free survival to first-line metastatic breast cancer, and to costs associated with pertuzumab. Probabilistic sensitivity analysis suggests that for node-positive patients, dual HER2-targeted therapy may be a cost-effective option.

CONCLUSIONS

The economic viability of dual HER2-targeted therapy was most pronounced in patients with node-positive high-risk early breast cancer. This study highlights the potential of dual HER2-targeted therapy as a cost-effective addition for these cases.

Apatinib and trastuzumab-based chemotherapy for heavily treated primary trastuzumab-resistant metastatic breast cancer

BACKGROUND

The low incidence and poor prognosis primary trastuzumab resistance (PTR) in HER2-positive breast cancer has limited research into possible treatments. Thus, it remains unclear whether this group of patients could benefit from nontargeting HER2 antiangiogenic therapy.

PATIENTS AND METHODS

We collected the medical data for HER2-positive patients with PTR who received apatinib 250 mg and trastuzumab-based chemotherapy (ATBC) between March 18, 2017, and March 31, 2022. All patients had progressed on ≥2 anti-HER2 treatments, including trastuzumab and small molecular tyrosine kinase inhibitors. We evaluated tumor response and safety profiles to ATBC over a median follow-up time of 34.5 months.

RESULTS

A total of 198 consecutively HER2-positive metastatic breast cancer patients were reviewed; 20 were PTR and received ATBC. The clinical benefit rate of the total cohort was 55.0%. No patient showed a complete response. The median PFS and overall survival (OS) of the entire cohort was 5.7 months (95% CI 2.9-8.5) and 24.6 months (95% CI 6.9-42.4), respectively. The estimated 2-year survival rate was 46.7% (95% CI 38.4-81.6%). The most common nonhematologic adverse events were hypertension (70.0%), hand-foot skin reaction (55.0%), proteinuria (40.0%), and cardiovascular decrease of LVEF (20.0%). No new toxicities were observed.

CONCLUSION

ATBC had favorable effects for PTR breast cancer patients in later line treatment. The toxicity of the triple-combination regimen was tolerable; thus, further research should focus on identifying PTR patients who could benefit from ATBC.

Updates in Treatment of HER2-positive Metastatic Breast Cancer

OPINION STATEMENT

The therapeutic landscape for HER2-positive metastatic breast cancer has exploded in the last two decades following the initial advent of trastuzumab, a monoclonal antibody. While the first line treatment has remained a combination of dual HER2 blockade with taxane chemotherapy, we now have several exciting options in the second line and beyond. The introduction of antibody-drug conjugates, in specific trastuzumab deruxtecan, has resulted in the best progression-free survival among patients with this subtype of breast cancer. Given the excellent outcomes of these drugs, clinical trials are now evaluating the role of ADCs in the front-line setting in previously untreated patients. In addition, there are also clinical trials evaluating the role of other targets in patients with HER2-positive cancers, including PI3KCA mutations, PD-L1 and CDK4/6. Given the predilection for brain metastases in this population, there is enthusiasm to identify the optimal combination of effective treatments. Tucatinib, capecitabine, and trastuzumab combination represent one such promising strategy. With the increasing longevity of these patients, important clinical questions include optimal treatment sequencing, the role of de-escalation of treatment in excellent responders, and the associated financial toxicity. Despite the aggressive nature of this subtype of breast cancer, the outcomes continue to improve for these patients with the evolving treatments.

Performance of a HER2 testing algorithm tailored for urothelial bladder cancer: A Bi-centre study

Aims

This study aimed to develop an AI algorithm for automated HER2 scoring in urothelial bladder cancer (UBCa) and assess the interobserver agreement using both manual and AI-assisted methods based on breast cancer criteria.

Methods and Results

We utilized 330 slides from two institutions for initial AI development and selected 200 slides for the ring study, involving six pathologists (3 senior, 3 junior). Our AI algorithm achieved high accuracy in two independent tests, with accuracies of 0.94 and 0.92. In the ring study, the AI-assisted method improved both accuracy (0.66 vs 0.94) and consistency (kappa=0.48; 95 % CI, 0.443-0.526 vs kappa=0.87; 95 % CI, 0.852-0.885) compared to manual scoring, especially in HER2-low cases (F1-scores: 0.63 vs 0.92). Additionally, in 62.3 % of heterogeneous HER2-positive cases, the interpretation accuracy significantly improved (0.49 vs 0.93). Pathologists, particularly junior ones, experienced enhanced accuracy and consistency with AI assistance.

Conclusions

This is the first study to provide a quantification algorithm for HER2 scoring in UBCa to assist pathologists in diagnosis. The ring study demonstrated that HER2 scoring based on breast cancer criteria can be effectively applied to UBCa. Furthermore, AI assistance significantly improves the accuracy and consistency of interpretations among pathologists with varying levels of experience, even in heterogeneous cases.

Risk of locoregional recurrence after breast cancer surgery by molecular subtype-a systematic review and network meta-analysis

BACKGROUND

The prevention of locoregional recurrence (LRR) is crucial in breast cancer, as it translates directly into reduced breast cancer-related death. Breast cancer is subclassified into distinct intrinsic biological subtypes with varying clinical outcomes.

AIMS

To perform a systematic review and network meta-analysis (NMA) to determine the rate of LRR by breast cancer molecular subtype.

METHODS

A NMA was performed as per PRISMA-NMA guidelines. Molecular subtypes were classified by St Gallen expert consensus statement (2013). Analysis was performed using R and Shiny.

RESULTS

Five studies were included including 6731 patients whose molecular subtypes were available. Overall, 47.3% (3182/6731) were Luminal A (LABC: estrogen receptor (ER) + /human epidermal growth factor receptor-2 (HER2) - /progesterone receptor (PR) + or Ki-67 < 20%), 25.5% (1719/6731) were Luminal B (LBBC: ER + /HER2 - /PR - or Ki-67 ≥ 20%), 11.2% (753/6731) were Luminal B-HER2 + (LBBC-HER2: ER + /HER2 +), 6.9% (466/6731) were HER2 + (HER2 ER - /HER2 +), and finally 9.1% (611/6731) were triple-negative breast cancer (TNBC: ER - /HER2 -). The median follow-up was 74.0 months and the overall LRR rate was 4.0% (271/6731). The LRR was 1.7% for LABC (55/3182), 5.1% for LBBC (88/1719), 6.0% for LBBC-HER2 (45/753), 6.0% for HER2 (28/466), and 7.9% for TNBC (48/611). At NMA, patients with TNBC (odds ratio (OR) 3.73, 95% confidence interval (CI) 1.80-7.74), HER2 (OR 3.24, 95% CI 1.50-6.99), LBBC-HER2 (OR 2.38, 95% CI 1.09-5.20), and LBBC (OR 2.20, 95% CI 1.07-4.50) were significantly more likely to develop LRR compared to LABC.

CONCLUSION

TNBC and HER2 subtypes are associated with the highest risk of LRR. Multidisciplinary team discussions should consider these findings to optimize locoregional control following breast cancer surgery.

Interobserver Variability in HER-2 Immunostaining Interpretation of Metastatic HER2 Low Breast Cancers in Cytology Specimens

BACKGROUND

Approximately, 55% of breast carcinomas are reported to be HER-2 low breast carcinomas. Trastuzumab-Deruxtecan is a new FDA-approved targeted therapy for HER-2 low metastatic breast carcinomas, making it essential that all efforts are made to identify these tumors in specimens submitted for pathologic examination. Cytology specimens are often the first and only modality of this assessment due to the ease of specimen procurement. This study aimed to determine the variability in HER-2 immunostaining interpretation among observers using cytologic specimens from metastatic sites.

DESIGN

A pathology database search was made to identify metastatic breast carcinoma reported in cytology specimens. A manual search was then done to identify cases of HER-2 low category, H&E cell block and HER-2 neu immunostain slides were retrieved for a total of 50 cases. Reviewer #1 and #2 independently interpreted HER-2 immunostain of all 50 cases. Only discordant cases were sent for reviewer-3 interpretation. All three were blinded by the metastatic site, and original HER-2 interpretation.

RESULTS

Of 50 cases, 11 cases (22%) were reported as concordant scores between reviewer #1 and reviewer #2 but had a discordant original IHC report. Additionally, 4 cases (8%) had discordant reporting of HER2 IHC stain between reviewer #1 and reviewer #2 making a total of 15 cases (30%) with overall discordant results.

CONCLUSION

This study highlights the interobserver variability of HER-2 immunostain interpretation for HER-2 low category of breast carcinomas. We recommend the need for more robust laboratory techniques including molecular for uniform identification of these unique targetable metastatic breast carcinoma groups.