Neoadjuvant trastuzumab, pertuzumab, and chemotherapy versus trastuzumab emtansine plus pertuzumab in patients with HER2-positive breast cancer (KRISTINE): a randomised, open-label, multicentre, phase 3 trial

Targeting programmed cell death pathways in gastric cancer: a focus on pyroptosis, apoptosis, necroptosis and PANoptosis

Gastric cancer (GC) is recognized as one of the most prevalent and serious malignancies, distinguished by its high incidence and fatality rates. Given the considerable mortality rate associated with GC, it is imperative to clarify the related pathways of GC development and further identify feasible targets for rational targeted therapy. Accumulating evidence reveals that programmed cell death (PCD) is a crucial element in both the progression and treatment of cancer. Pyroptosis, apoptosis, and necroptosis are three well-studied types of PCD, and a link between them and GC has been established in recent studies. PANoptosis, a comparatively novel type of PCD, shares key traits with pyroptosis, apoptosis, and necroptosis, yet cannot be entirely illustrated by any single model. PANoptosis has been discovered to exert an impact on multiple diseases, including cancer, infections, and inflammatory conditions, consequently offering novel perceptions into the progression and treatment of GC. This review seeks to encapsulate the emerging roles and therapeutic potential of pyroptosis, apoptosis, necroptosis, and PANoptosis in GC, laying the groundwork for the advancement of innovative treatment methods that target important signaling pathways connected with these four forms of PCD.

Comparison of paclitaxel and docetaxel in dual HER2 blockade: efficacy and safety in neoadjuvant treatment of HER2-positive breast cancer

BACKGROUND

Dual HER2 blockade with trastuzumab and pertuzumab combined with neoadjuvant chemotherapy improves outcomes in HER2-positive breast cancer. The optimal taxane backbone (paclitaxel vs. docetaxel) remains unclear.

METHODS

This retrospective study included 220 HER2-positive breast cancer patients treated with anthracycline-based chemotherapy followed by dual HER2 blockade with trastuzumab, pertuzumab, and either paclitaxel (80 mg/m2 for 12 weeks) or docetaxel (75 mg/m2 every three weeks for four cycles). Pathological complete response (pCR), disease-free survival (DFS), overall survival (OS), and toxicity profiles were analyzed.

RESULTS

At the time of diagnosis, 6% of the patients included in the study were at stage I, 70.4% were at stage II, and 23.6% were at stage III. The overall pCR rate was 55%, with no significant difference between the paclitaxel (57.9%) and docetaxel (52.2%) groups (p = 0.418). Higher pCR rates were associated with grade 3 tumors, ER/PR negativity, and Ki- 67 ≥ 20%. Patients achieving pCR had significantly lower relapse rates (2.5% vs. 16.2%, p < 0.001). These factors were significantly associated with pCR in univariate analysis but did not remain independent predictors in multivariate analysis. DFS and OS were higher in the paclitaxel group compared to the docetaxel group (DFS: 96.3% vs. 83.2%, p = 0.025; OS: 100% vs. 95.5%, p = 0.042). Grade 3-4 anemia was more frequent with docetaxel (23% vs. 9%, p = 0.007).

CONCLUSION

Both paclitaxel and docetaxel are effective in neoadjuvant dual HER2 blockade regimens. Paclitaxel demonstrated better DFS, OS, and a favorable safety profile, supporting its use as a preferred option.

Role of imaging based response assesment for adapting neoadjuvant systemic therapy for breast cancer: A systematic review

PURPOSE

The objective of this systematic review is to investigate the role of imaging in response monitoring during neoadjuvant systemic therapy (NST) for breast cancer and assess whether treatment modifications based on imaging response are implemented in clinical practice.

METHODS

A systematic review was conducted, analyzing five clinical practice guidelines and 147 clinical trial publications involving NST for breast cancer. The snowballing technique was employed, using a "start set" of clinical guidelines to trace relevant trials. Additionally, a PubMed search was conducted to identify trials published between 2023-2024. The review analyzed the use of imaging modalities, timing, and response criteria, and whether escalation, de-escalation, or change of treatment occurred based on imaging response.

RESULTS

Imaging was utilized in 81 % (119/147) of the trials, with ultrasound, MRI, and mammography being the most frequently employed modalities. Mid-treatment imaging was applied in 56 % (83/147) of the trials. However, only 15 % (22/147) of the trials implemented treatment modifications based on imaging response, highlighting the limited application of imaging response-guided therapy. No standardized imaging protocols or consistent response-guided treatment strategies were identified across the trials or clinical practice guidelines, with considerable variability in imaging methods, timing, and response criteria.

CONCLUSION

This systematic review underscores the critical need for standardized imaging protocols, response assessment criteria and image-guided treatment decisions. It is therefore evident that imaging for response monitoring during treatment should preferably be performed within clinical trials.

Efficacy and safety of neoadjuvant SHR-A1811 with or without pyrotinib in women with locally advanced or early HER2-positive breast cancer: a randomized, open-label, phase II trial

BACKGROUND

Standard neoadjuvant regimens for human epidermal growth factor receptor 2 (HER2)-positive breast cancer include trastuzumab and pertuzumab combined with chemotherapy, and the efficacy and safety of third-generation HER2-directed antibody-drug conjugate (ADC) remain to be elucidated.

PATIENTS AND METHODS

This open-label, randomized, phase II study enrolled patients aged ≥18 years with stage II-III HER2-positive breast cancer. Patients were randomly assigned (1 : 1 : 1) to receive neoadjuvant treatment either with SHR-A1811 monotherapy, SHR-A1811 with pyrotinib, or nab-paclitaxel combined with carboplatin, trastuzumab, and pertuzumab (PCbHP) for 24 weeks. The primary endpoint was pathological complete response (pCR). Safety was analysed in patients who received at least one dose of study medication.

RESULTS

Between 27 December 2022 and 11 February 2024, 265 patients were randomly allocated to neoadjuvant, mono-SHR-A1811 (n = 87), SHR-A1811 plus pyrotinib (n = 88), or PCbHP (n = 90). The baseline characteristics were well balanced; ∼45% of the patients were hormone receptor (HR) positive, and 70% of the patients were stage III. The pCR rate was 63.2% for mono-SHR-A1811 (50% for HR positive and 74.5% for HR negative), 62.5% for SHR-A1811 plus pyrotinib (44.7% for HR positive and 76% for HR negative), and 64.4% for PCbHP (54.1% for HR positive and 71.7% for HR negative), with no significant difference between the groups. Grade ≥3 treatment-related adverse events occurred in 44.8% of patients with mono-SHR-A1811, 71.6% with SHR-A1811 plus pyrotinib, and 38.8% with PCbHP. One patient experienced grade 2 interstitial lung disease in SHR-A1811, 9.1% of patients experienced grade 3 diarrhoea in SHR-A1811 plus pyrotinib, and no treatment-related deaths occurred.

CONCLUSIONS

This is the first study to report the efficacy and safety of third-generation HER2-directed ADC in the neoadjuvant setting for HER2-positive breast cancer. SHR-A1811 showed robust activity, with a tolerable safety profile.

Efficacy and safety of inetetamab plus pertuzumab and nab-paclitaxel as neoadjuvant therapy for HER2+ breast cancer: A single-arm multicenter phase II clinical trial

The combination of inetetamab and vinorelbine has demonstrated survival benefits with an acceptable toxicity profile in HER2+ metastatic breast cancer (MBC) patients. This multicenter, single-arm, phase II trial further evaluates the efficacy of inetetamab combined with pertuzumab and nab-paclitaxel as neoadjuvant therapy. Treatment-naïve patients with HER2+ early-stage or locally advanced BC received four cycles of intravenous inetetamab (8 mg/kg loading dose, then 6 mg/kg for subsequent doses), intravenous pertuzumab (840 mg loading dose, then 420 mg for subsequent doses), and weekly nab-paclitaxel (125 mg/m2). The primary endpoint was the total pathological complete response (tpCR) rate, defined as ypT0/is and ypN0, assessed by independent central review. From March 2023 to February 2024, 62 patients were enrolled, with the majority (61/62) completing 4 cycles of neoadjuvant therapy. The tpCR rate was 56.5% (95% CI: 43.3%-69.0%). Further analysis showed that patients with estrogen receptor (ER) negative tumors derived greater benefit, with a tpCR rate of 90.9%. The objective response rate was 90.3% (95% CI: 80.1%-96.4%). The most common grade 3 or higher adverse events were neutropenia (32.3%), decreased white blood cell count (19.4%), infectious pneumonia (3.2%), anemia (3.2%), and diarrhea (3.2%). No death occurred during the neoadjuvant treatment. Neoadjuvant treatment with inetetamab, in combination with pertuzumab and nab-paclitaxel, demonstrates good efficacy and tolerability, especially in ER-negative patients.

Breast Tumor-Bed Biopsy for Pathological Complete Response Prediction: The NRG-BR005 Nonrandomized Clinical Trial

Importance

Use of modern neoadjuvant chemotherapy (NAC) regimens has markedly increased rates of pathologic complete response (pCR) in breast cancer, raising the question of whether surgical removal of the primary tumor is required for patients with pCR. For surgery to be omitted, one must be able to accurately predict pCR before surgery.

Objective

To investigate if adding post-NAC core needle biopsy of the tumor bed to trimodality imaging in patients who have clinical complete response (cCR) will predict pCR (resolution of both invasive disease and ductal carcinoma in situ) in 90% or more cases.

Design, Setting, and Participants

This was a phase 2, prospective, nonrandomized clinical trial. Patients were enrolled from August 2017 to June 2019. This is the final analysis, which was completed in December 2023. The setting included academic and community hospital center members of NRG (ie, the National Surgical Adjuvant Breast and Bowel Project, the Radiation Therapy Oncology Group, and the Gynecologic Oncology Group) in the US and Canada. Patients with operable (T1-T3, stage I-III) invasive ductal carcinoma who completed NAC and achieved cCR and radiological complete response (rCR) or near rCR by mammography (mass ≤1 cm and no malignant microcalcifications), ultrasound (mass ≤2 cm), and magnetic resonance imaging (no mass with rapid rise or washout kinetics).

Interventions

Patients underwent marker-directed stereotactic multiple-core needle biopsy of the tumor bed with marker placement before breast-conservation surgery.

Main Outcomes and Measures

End points were negative predictive value (NPV) and sensitivity of the biopsy.

Results

A total of 105 patients were enrolled with 101 evaluable (mean [SD] age, 52.8 [10.5] years); 77 patients (76.2%) were younger than 60 years, and all breast cancer subtypes were represented with 32 (31.7%) triple-negative breast cancer, 21 (20.8%) hormone receptor-positive/epidermal growth factor receptor 2 (ERBB2; formerly HER2)-negative (ERBB2-) breast cancer, and 46 (45.5%) ERBB2-positive (ERBB2+) breast cancer. In 101 evaluable patients, 36 had residual disease at surgery (pCR = 64%). With imaging criteria, NPV of the biopsy was 78.3% (95% CI, 67.9%-86.6%), and the sensitivity of the biopsy was 50% (95% CI, 32.9%-67.1%). In an exploratory subset analysis, the NPV in patients with ERBB2+ breast cancer was 90% (95% CI, 76.3%-97.2%). On retrospective central review, 62 of 101 enrolled patients met imaging eligibility criteria. In this exploratory post hoc analysis, NPV in these patients was 86.8% (95% CI, 74.7%-94.5%).

Conclusions and Relevance

These findings do not support breast conservation treatment without surgery based on the study criteria for cCR and rCR/near rCR by trimodality imaging and negative tumor-bed biopsy. Strict adherence to imaging criteria may be required to achieve acceptable predictive values.

TRIAL Registration

ClinicalTrials.gov Identifier: NCT03188393.

Chemotherapy-free neoadjuvant pembrolizumab combined with trastuzumab and pertuzumab in HER2-enriched early breast cancer (WSG-KEYRICHED-1): a single-arm, phase 2 trial

BACKGROUND

Accumulating evidence indicates that about 30-40% of patients with HER2-positive early breast cancer might achieve excellent outcomes without chemotherapy. Therefore, we aimed to test the pathological complete response after the addition of pembrolizumab to dual anti-HER2 blockade and omission of chemotherapy in patients with HER2-enriched breast cancer.

METHODS

WSG-KEYRICHED-1 was a single-arm, multicentre, open-label, hypothesis-generating phase 2 trial done at 15 breast cancer centres in Germany. Women aged 18 years and older, with previously untreated clinical stage T1c-T3, N0-N2, M0, primary unilateral early invasive breast cancer, and locally confirmed HER2 immunohistochemistry score 2+ or 3+ status, and hormone receptor-positive or receptor-negative status, were enrolled. Women with centrally confirmed HER2-enriched subtype by prediction analysis of microarrays 50 gene set (PAM50) and an Eastern Cooperative Oncology Group performance status of 0-1 were allocated to four cycles of intravenous pembrolizumab (200 mg every 3 weeks for 12 weeks), intravenous trastuzumab biosimilar ABP 980 (8 mg/kg loading dose, then 6 mg/kg every 3 weeks for 12 weeks), and intravenous pertuzumab (840 mg loading dose, then 420 mg every 3 weeks for 12 weeks). The primary outcome was the proportion of patients with a pathological complete response (defined as ypN0 or ypT0/is), assessed in the full analysis set, which included all patients who had at least one dose of trial treatment and had central tumour assessment within 3 weeks after the end of trial treatment. For the primary endpoint to be met, at least 52·2% of patients had to have a pathological complete response to support the hypothesis that the proportion of patients with pathological complete response after trial treatment would be higher than 40% with statistical significance. Safety was analysed in all patients who had at least one dose of trial treatment. The study is registered with ClinicalTrials.gov, NCT03988036, and has been completed.

FINDINGS

Between Sept 2, 2020, and May 5, 2021, 48 women were enrolled, of whom four did not have surgery, and one had only a local pathological complete response assessment. Therefore, 43 patients with central pathological complete response assessment were included in the full analysis set. Median follow-up was 8·6 months (IQR 8·3-9·0). 20 (47%) of 43 patients had a pathological complete response by central assessment (lower bound of the one-sided 95% CI 33%), thus the null hypothesis (40% pathological complete response) could not be rejected (p=0·22). Four (8%) of 48 patients had grade 3-4 adverse events deemed related to drug treatment. The most common grade 3-4 adverse events were increased alanine aminotransferase (n=1), drug hypersensitivity (n=1), nephritis (n=1), and panic attack (n=1). Serious adverse events occurred in four (8%) of 48 patients, which were drug hypersensitivity (n=1), panic attack (n=1), pyrexia (n=1), and COVID-19 (n=1). Pembrolizumab was discontinued or postponed due to adverse events in three (6%) of 48 patients. No deaths occurred.

INTERPRETATION

Although the null hypothesis could not be rejected, the WSG-KEYRICHED-1 trial highlights the potential of a short chemotherapy-free combination of pembrolizumab with dual anti-HER2 therapy, warranting the initiation of randomised trials investigating the immunotherapy without chemotherapy in patients with HER2-enriched breast cancer.

FUNDING

Merck Sharp & Dohme and NanoString Technologies.

HER2 (2+)/SISH-positive vs. HER2 (3+) Breast Cancer: Pre-treatment MRI Differences and Accuracy of pCR Prediction on Post-treatment MRI

RATIONALE AND OBJECTIVES

To evaluate whether HER2 (human epidermal growth factor receptor 2) (2+)/SISH (silver-enhanced in situ hybridization)+ and HER2 (3+) breast cancers exhibit distinct imaging characteristics on pre-treatment MRI and assess differences in pCR (pathologic complete response) prediction accuracy on post-treatment MRI, considering interobserver variability.

METHODS

This retrospective study included 301 HER2-positive breast cancer patients (mean age, 54 ± 10 years) who underwent NAC and surgery. Pre-treatment MRI features were analyzed in consensus. Two radiologists independently assessed post-treatment MRI for shrinkage patterns and response according to RECIST v1.1, further categorizing complete responses into rCR (radiologic complete response) and near-rCR. Interobserver agreement was measured (Cohen's kappa), and pCR was defined as no residual invasive or in situ tumor in the breast (ypT0) on the final pathology report. Sensitivity, specificity, and AUC were used to evaluate pCR prediction.

RESULTS

Fifty-four patients had HER2 (2+)/SISH+ and 247 had HER2 (3+) tumors. pCR rates were significantly higher in HER2 (3+) (58.7% vs. 18.5%, p < 0.001). On pre-treatment MRI, HER2 (2+)/SISH+ tumors more often appeared as single masses, while HER2 (3+) tumors showed more NME (non-mass enhancement) (44.5% vs. 16.7%, p < 0.001) and mass with NME (33.6% vs. 9.3%, p = 0.005). Post-treatment MRI showed simple concentric shrinkage in HER2 (2+)/SISH+ and no enhancement in HER2 (3+). Agreement was moderate (κ = 0.541-0.588). For pCR prediction, rCR alone yielded AUCs ranging from 0.659 to 0.756. Adding near-rCR improved specificity but reduced sensitivity, with a significant AUC increase for one reader (p = 0.011).

CONCLUSION

Pre-treatment MRI revealed distinct imaging characteristics between subgroups. While pCR rates were higher in HER2 (3+), MRI-based pCR prediction showed similar performance, though near-rCR reduced sensitivity.

HER2 mRNA Score From Quantitative ERBB2 mRNA Expression of Oncotype Dx : Can It Replace the HER2 Immunohistochemistry?

As novel human epidermal growth factor receptor-2 (HER2) and drug conjugates have proven to be effective treatments for both HER2-positive breast cancer (BC) and HER2-low BC, the need to develop more accurate methods to quantify HER2 status has increased. We compared the correlation between the HER2 mRNA score (HS), obtained using the Oncotype DX (ODX) test, and HER2 immunohistochemistry (IHC) to verify the accuracy of HER2 quantification and its correlation with clinicopathologic characteristics. We retrospectively collected ODX test data from 1524 estrogen-receptor positive, HER2-negative patients with BC. No significant differences in clinicopathologic characteristics, including ODX Recurrence Score (RS), were observed between HER2-0 and HER2-low BC. The median HS value of the HER2-low subgroup was significantly higher than that of the HER2-0 subgroup ( P <0.001) and increased significantly between the 4 subgroups classified by HER2 IHC ( P <0.001). The receiver operating characteristic curve showed acceptable utility in distinguishing HER2-0 from HER2-low (area under the curve=0.76) and HER2-null and HER2-ultralow subgroups (area under the curve=0.81), but the overlap between subgroups was also prominent. After defining 8.9 as a suboptimal cutoff mRNA score, multivariate analysis revealed that low Ki-67 (<20%) and RS (≤25) were statistically associated with higher HS (>8.9), whereas progesterone receptor negativity, high Ki-67, high nuclear grade, lower HS, and older age (>50 y) were statistically associated with high RS. Our study revealed that HS is significantly associated with HER2 IHC results and clinicopathologic parameters other than HER2 IHC.

Pharmacovigilance study of adverse reactions of anti-HER-2 drugs for the treatment of HER-2-positive breast cancer based on the FAERS database

OBJECTIVE

There are three categories of drugs that treat human epidermal growth factor receptor type 2 (HER-2) positive breast cancer: monoclonal antibodies (mAbs), antibody-drug conjugates (ADCs), and tyrosine kinase inhibitors (TKIs). The purpose of this study is to analyze and compare the adverse reactions of three classes of anti-HER-2 drugs to various body systems in patients based on the FDA Adverse Event Reporting System (FAERS).

METHODS

All data reports were extracted from the FAERS between 2004 and 2024. Data mining of adverse events associated with anti-HER-2 drugs was carried out using disproportionality analysis. A multivariate logistic regression analysis was conducted to explore the risk factors associated with AEs leading to hospitalization.

RESULTS

A total of 47,799 patients were screened for the three classes of drugs, among which ADC drugs caused the largest proportion of deaths. MAb has the strongest ADR signals associated with "cardiac disorders". Moreover, trastuzumab was associated with a greater risk of cardiotoxicity. Logistic regression analysis revealed that the treatment with mAbs should be wary of serious adverse reactions in "infections and infestations" and "metabolism and nutrition disorders". Moreover, "endocrine disorders" were the factor associated with the highest risk of prolonged hospitalization due to trastuzumab deruxtecan (T-DXd). The safety of tucatinib among TKI drugs is greater than that of other drugs.

CONCLUSION

In general, from the perspective of the effects of the three classes of drugs on the various body systems of patients, we should focus on mAb-associated "cardiac disorders", ADC-associated "hepatobiliary disorders", "respiratory, thoracic and mediastinal disorders", and TKI-associated "gastrointestinal disorders.

Multiparametric MRI-based Interpretable Machine Learning Radiomics Model for Distinguishing Between Luminal and Non-luminal Tumors in Breast Cancer: A Multicenter Study

RATIONALE AND OBJECTIVES

To construct and validate an interpretable machine learning (ML) radiomics model derived from multiparametric magnetic resonance imaging (MRI) images to differentiate between luminal and non-luminal breast cancer (BC) subtypes.

METHODS

This study enrolled 1098 BC participants from four medical centers, categorized into a training cohort (n = 580) and validation cohorts 1-3 (n = 252, 89, and 177, respectively). Multiparametric MRI-based radiomics features, including T1-weighted imaging (T1WI), T2-weighted imaging (T2WI), diffusion-weighted imaging (DWI), apparent diffusion coefficient (ADC), and dynamic contrast-enhanced (DCE) imaging, were extracted. Five ML algorithms were applied to develop various radiomics models, from which the best performing model was identified. A ML-based combined model including optimal radiomics features and clinical predictors was constructed, with performance assessed through receiver operating characteristic (ROC) analysis. The Shapley additive explanation (SHAP) method was utilized to assess model interpretability.

RESULTS

Tumor size and MR-reported lymph node status were chosen as significant clinical variables. Thirteen radiomics features were identified from multiparametric MRI images. The extreme gradient boosting (XGBoost) radiomics model performed the best, achieving area under the curves (AUCs) of 0.941, 0.903, 0.862, and 0.894 across training and validation cohorts 1-3, respectively. The XGBoost combined model showed favorable discriminative power, with AUCs of 0.956, 0.912, 0.894, and 0.906 in training and validation cohorts 1-3, respectively. The SHAP visualization facilitated global interpretation, identifying "ADC_wavelet-HLH_glszm_ZoneEntropy" and "DCE_wavelet-HLL_gldm_DependenceVariance" as the most significant features for the model's predictions.

CONCLUSION

The XGBoost combined model derived from multiparametric MRI may proficiently differentiate between luminal and non-luminal BC and aid in treatment decision-making.

CRITICAL RELEVANCE STATEMENT

An interpretable machine learning radiomics model can preoperatively predict luminal and non-luminal subtypes in breast cancer, thereby aiding therapeutic decision-making.

Screening and exploration of neoadjuvant "de-escalation" therapy for early breast cancer

Background

Neoadjuvant therapy for breast cancer improves the prognosis of high-risk patients. However, whether pathological completed response (pCR) can be used as a surrogate endpoint for de-escalation therapy in patients who are relatively sensitive to treatment remains to be elucidated.

Methods

We retrospectively reviewed 143 breast cancer patients, with clinical stage (cStage) II-IIIA who received neoadjuvant chemotherapy and achieved pCR in a short time (within 16 weeks) from 2012 to 2022. The prognosis of patients was analysed using the Kaplan-Meier method, Cox proportional hazards regression models to identify independent clinicopathologic factors affecting prognosis.

Results

The median follow-up period was 47 months, the overall 4-year disease-free survival (DFS) and overall survival (OS) were 95.3% and 96.9%, respectively, in 143 patients with pCR after neoadjuvant chemotherapy. The 4-year DFS between the postoperative adjuvant chemotherapy and no adjuvant chemotherapy groups was 76.4% and 95.2%, with a significant statistical difference between both groups (P < 0.05). For HER2-positive (HER2+) and Triple negative breast cancer (TNBC), the addition of targeted therapy or platinum-based drugs had no impact on prognosis. Univariate and multivariate analyses of prognosis showed that only postoperative adjuvant chemotherapy significantly affected prognosis.

Conclusion

Patients with operable cStage II-IIIA breast cancer who achieved pCR after a short period of neoadjuvant chemotherapy have a satisfactory prognosis and may be suitable for chemotherapy "de-escalation." This approach is also a dominant application of neoadjuvant "tailoring therapy."

Toxicities and management strategies of emerging antibody-drug conjugates in breast cancer

Antibody-drug conjugates (ADCs) offer a promising therapeutic approach for various cancers, enhancing the therapeutic window while mitigating systemic adverse effects on healthy tissues. ADCs have achieved remarkable clinical success, particularly in treating breast cancer, becoming a standard therapy across all subtypes, including hormone receptor-positive, human epidermal growth factor receptor 2-positive, and triple-negative breast cancer. Although designed to selectively target antigens via monoclonal antibodies, ADCs can exhibit toxicity in normal tissues, often due to off-target effects of their cytotoxic payloads. Understanding and managing these toxicities according to established guidelines are crucial for enhancing ADC clinical efficacy, minimizing adverse events, and ultimately improving patient outcomes. This review comprehensively examines the toxicities of ADCs employed in breast cancer treatment and explores their management strategies. Furthermore, we investigate novel ADCs beyond trastuzumab deruxtecan and sacituzumab govitecan, evaluating their potential efficacy and corresponding safety profiles.

Antibody-drug conjugates in breast cancer: current evidence and future directions

Antibody-drug conjugates (ADCs) are a rapidly evolving class of antitumor drugs and have already revolutionized the treatment strategy of many hematologic and solid cancers. So far, trastuzumab emtansine (T-DM1), trastuzumab deruxtecan (T-DXd), sacituzumab govitecan (SG) and datopotamab deruxtecan (Dato-DXd) are the four ADCs that have been approved by US food and drug administration (FDA) in treatment of breast cancer, and SKB264 has been approved by Chinese national medical products administration (NMPA). Many ADCs for treatment of breast cancer are currently being tested in late-phase clinical trials, with several encouraging results achieved recently. However, major issues arise during the use of ADCs, including emergence of acquired resistance, occurrence of treated-related toxicities, and identification of biomarkers of response and resistance. ADCs are being increasingly tested in combination with other agents, and novel next-generation ADC development is progressing rapidly. A better understanding of the design and development of ADCs will promote ADC development for cancer treatment. In this review, we aim to provide a broad overview of the design and the recent advances of ADCs in breast cancer. We also propose several notable future directions of ADCs in treatment of breast cancer.

HER2-targeted therapy in colorectal cancer: a comprehensive review

Colorectal cancer (CRC) is the third most common cancer and the second leading cause of cancer-related deaths worldwide. Despite treatment advancements in the last decades, CRC remains heterogeneous with significant clinical and genetic diversity. Human epidermal growth factor receptor 2 (HER2) proto-oncogene plays a critical role, as its amplification or overexpression leading to abnormal cell proliferation and tumorigenesis. HER2 overexpression or amplification is identified in 2-4% of metastatic CRCs (mCRC) patients, representing a potential therapeutic target. It is also associated with resistance against epidermal growth factor receptor (EGFR)-targeted therapies like cetuximab and panitumumab, for treatment of RAS wild-type mCRC. Although HER2-positive mCRC is rare, assessing HER2 levels is important. Furthermore, anti-HER2 therapies exhibited non-toxic profile and high efficacy in chemorefractory cases. This review delves into modern management of anti-HER2 therapies in CRC with a particular focus on recent advances and current knowledge about the prognostic and predictive value of HER2.

HER2-positive gastric cancer: from targeted therapy to CAR-T cell therapy

Gastric cancer (GC) ranks as the fifth most prevalent cancer on a global scale, with HER2-positive GC representing a distinct subtype that exhibits more intricate biological characteristics. Conventional chemotherapy typically exhibits restricted efficacy in the management of HER2-positive GC. In light of the incessant advancement in molecular targeted therapies, targeting HER2 has emerged as a promising therapeutic approach for this subtype. The advent of antibody-drug conjugates (ADCs) and chimeric antigen receptor T-cell therapy (CAR-T) has furnished novel treatment alternatives for HER2-positive GC. Nevertheless, owing to the pronounced heterogeneity of GC and the complex tumor microenvironment, drug resistance frequently emerges, thereby substantially influencing the effectiveness of HER2-targeted therapy. This article comprehensively summarizes and deliberates upon the strategies of HER2-targeted therapy as well as the underlying resistance mechanisms.

Pertuzumab in Combination with Trastuzumab and Docetaxel as Adjuvant Doublet Therapy for HER2-Positive Breast Cancer: A Systematic Review

Breast cancer is the most clinically relevant pathology of the mammary gland and is currently the most diagnosed malignant disease among women worldwide. In breast cancer prevention, it is important to consider that the risk of developing the disease is not the same for the entire population. This pathology presents heterogeneous clinical manifestations and the most common classification is related to the following hormonal receptors: estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2), and triple-negative (TNBC). Currently, a new class of therapy is being used for cancer treatment: anti-body-drug conjugates. A bibliographic search was performed by establishing keywords and then combining them using Boolean operators OR and AND. Thus, the search equation was formulated according to the PICO search question to be used in the PubMed database. Results: Fifteen studies that met the established inclusion criteria were analyzed, and their methodological quality was assessed using the Joanna Briggs Institute approach, demonstrating high reliability in the results obtained, the analyzed studies focus on the combination of adjuvant Pertuzumab + Trastuzumab with chemotherapy for the treatment of HER2-positive breast cancer. Scientific evidence suggests that the combination of pertuzumab and trastuzumab not only improves the survival of patients with HER2-positive breast cancer but also provides a safe and flexible treatment option.

Breast cancer: pathogenesis and treatments

Breast cancer, characterized by unique epidemiological patterns and significant heterogeneity, remains one of the leading causes of malignancy-related deaths in women. The increasingly nuanced molecular subtypes of breast cancer have enhanced the comprehension and precision treatment of this disease. The mechanisms of tumorigenesis and progression of breast cancer have been central to scientific research, with investigations spanning various perspectives such as tumor stemness, intra-tumoral microbiota, and circadian rhythms. Technological advancements, particularly those integrated with artificial intelligence, have significantly improved the accuracy of breast cancer detection and diagnosis. The emergence of novel therapeutic concepts and drugs represents a paradigm shift towards personalized medicine. Evidence suggests that optimal diagnosis and treatment models tailored to individual patient risk and expected subtypes are crucial, supporting the era of precision oncology for breast cancer. Despite the rapid advancements in oncology and the increasing emphasis on the clinical precision treatment of breast cancer, a comprehensive update and summary of the panoramic knowledge related to this disease are needed. In this review, we provide a thorough overview of the global status of breast cancer, including its epidemiology, risk factors, pathophysiology, and molecular subtyping. Additionally, we elaborate on the latest research into mechanisms contributing to breast cancer progression, emerging treatment strategies, and long-term patient management. This review offers valuable insights into the latest advancements in Breast Cancer Research, thereby facilitating future progress in both basic research and clinical application.

Tumor-infiltrating lymphocytes in HER2-positive breast cancer: potential impact and challenges

INTRODUCTION

In this review, we evaluate the role of stromal tumor-infiltrating lymphocytes (sTILs) as a biomarker in human epidermal growth factor receptor 2 (HER2)-positive breast cancer, exploring the prognostic and predictive potential in various treatment settings.

METHODS

Data from multiple clinical trials in the early and metastatic settings, focusing on TILs' correlation with pathologic complete response (pCR), progression-free survival (PFS), and overall survival across early and metastatic HER2-positive breast cancer were summarized. This review also discusses TILs' assessment methods, interobserver variability, and emerging technologies to assess TILs.

RESULTS

TILs have been identified as a highly reproducible biomarker that predicts pCR in patients receiving neoadjuvant therapy and serves as a prognostic indicator for long-term outcomes in several breast cancer subtypes, including HER2-positive. Studies indicate that higher TIL levels correlate with better recurrence-free survival rates. Despite these findings, there is no consensus on the optimal TIL threshold for clinical decision making, and further research is required on how to incorporate TILs into routine clinical practice.

CONCLUSIONS

TILs represent a promising biomarker in HER2-positive breast cancer, particularly in early disease settings. This assessment could guide treatment de-escalation or intensification, tailoring therapies to individual patient profiles. Due to their prognostic importance, TILs can be added to pathology reports. However, further validation in clinical trials is essential for the widespread adoption of TILs in clinical practice.

Poor response of HER2-positive mucinous carcinomas of breast to neoadjuvant HER2-targeted therapy: A study of four cases

BACKGROUND

Breast mucinous carcinoma (MC) is typically positive for estrogen receptor (ER) and progesterone receptor (PR) expressions and negative for human epidermal growth factor receptor (HER2) overexpression. HER2 positive MC is a rare entity; its response to neoadjuvant HER2-targeted therapy remains unclear.

METHODS

Four cases of HER2 positive MC and seven cases of HER2 positive invasive ductal carcinoma with mucinous features (MCF) were identified. Clinicopathologic features were collected. Patients' germline data was gathered if available. Tumor's response to HER2-directed treatment were recorded and compared.

RESULTS

Two HER2 positive MCs were treated with neoadjuvant HER2-directed treatment and showed no response in the subsequent surgical resection specimens including one positive lymph node showing no treatment effect. One patient had upfront surgery. The fourth patient presented with advanced stage and showed progression on HER2-directed treatment. Six HER2 positive MCFs received neoadjuvant HER2-directed therapy; two cases showed complete pathologic response and four had only minimal residual carcinomas in the breast. Two cases with positive lymph nodes had complete response in the lymph nodes. The seventh patient presented at an advanced stage and was stable on HER2-directed treatment.

CONCLUSIONS

Our findings suggest that HER2 positive MCs may be resistant to HER2-directed treatment. This is in contrast with the excellent treatment response observed in HER2 positive MCFs. It is important to report mucinous carcinoma percentage in biopsies on HER2 positive tumors as it may be related to treatment response. Further investigation of the underlying mechanisms may help optimize clinical management in this patient population.

Resistance to antibody-drug conjugates: A review

Antibody-drug conjugates (ADCs) are antitumor drugs composed of monoclonal antibodies and cytotoxic payload covalently coupled by a linker. Currently, 15 ADCs have been clinically approved worldwide. More than 100 clinical trials at different phases are underway to investigate the newly developed ADCs. ADCs represent one of the fastest growing classes of targeted antitumor drugs in oncology drug development. It takes advantage of the specific targeting of tumor-specific antigen by antibodies to deliver cytotoxic chemotherapeutic drugs precisely to tumor cells, thereby producing promising antitumor efficacy and favorable adverse effect profiles. However, emergence of drug resistance has severely hindered the clinical efficacy of ADCs. In this review, we introduce the structure and mechanism of ADCs, describe the development of ADCs, summarized the latest research about the mechanisms of ADC resistance, discussed the strategies to overcome ADCs resistance, and predicted biomarkers for treatment response to ADC, aiming to contribute to the development of ADCs in the future.

Adjuvant Trastuzumab Plus Pertuzumab Versus Trastuzumab Alone in Patients Achieving Pathologic Complete Response After Chemotherapy With Trastuzumab and Pertuzumab: A Retrospective Cohort Study

BACKGROUND

For patients who achieve pathologic complete response (pCR) after neoadjuvant chemotherapy with trastuzumab (T) and pertuzumab (P), the benefit of adding P to T remains uncertain. We compared survival outcomes according to the type of adjuvant anti-HER2 therapy in patients with pCR after chemotherapy with TP.

METHOD

Patients who achieved pCR in both the breast and axilla after neoadjuvant chemotherapy with TP were included. Recurrence-free survival (RFS) and distant recurrence-free survival (DRFS) were evaluated. Univariate and multivariate Cox proportional hazards analyses were used to assess the impact of different adjuvant therapies on RFS and DRFS.

RESULTS

In total, 386 patients were included, with 69 (17.9%) receiving adjuvant TP and 317 (82.1%) receiving adjuvant T alone. At a median follow-up of 49 months, the 3-year RFS rate was 96.1%. There was no significant difference in the 3-year RFS between groups (94.2% in TP and 95.6% in T), with an adjusted hazard ratio (HR) of 1.15 (95% CI, 0.37-3.55, P = .806). In the clinical node-positive group (n = 294), there was no difference in survival between groups (HR 1.64, 95% CI, 0.58-4.65, P = .35). The multivariate analysis showed no significant predictors of recurrence or distant recurrence, including clinical tumor size, nodal status, ER/PR/HER2 status, and adjuvant radiotherapy receipt. Among 11 patients with brain metastasis after pCR, there was no difference according to the type of adjuvant anti-HER2 therapy.

CONCLUSIONS

In patients with pCR who responded to chemotherapy and dual HER2 blockade (TP), the 3-year RFS and brain metastasis-free survival did not differ according to the type of adjuvant anti-HER2 therapy.

Effect of different intraoperative blood pressure regulation levels on postoperative myocardial injury in patients undergoing radical mastectomy for breast cancer after receiving neoadjuvant chemotherapy: a study protocol for a randomised controlled trial

INTRODUCTION

For patients with breast cancer receiving preoperative neoadjuvant chemotherapy with anthracyclines, there is an increased risk of postoperative myocardial injury due to the cardiotoxicity of the chemotherapeutic agents. The optimal intraoperative blood pressure regulation regimen for these patients is unclear. This study is being conducted to determine whether targeting mean arterial pressure (MAP) to 100%-120% of the patient's baseline blood pressure reduces the incidence of myocardial injury after non-cardiac surgery (MINS) compared with targeting MAP to 80%-100%. MINS is defined as elevated cardiac troponin levels within 30 days after non-cardiac surgery with or without clinical and electrocardiographic signs of cardiac ischaemia.

METHODS AND ANALYSIS

The study is a single-centre, single-blind, prospective randomised controlled trial. It is expected to enrol 166 subjects receiving neoadjuvant chemotherapy with anthracyclines, between the ages of 40 and 75 years, scheduled for radical mastectomy. Participants will be randomised 1:1 to a lower-level group:intraoperative MAP control at 80%-100% of baseline values or a higher-level group:intraoperative MAP control at 100%-120% of baseline values. The primary outcome is defined by the incidence of MINS at 6-8 hours, 24 hours and 48 hours postoperatively. The secondary outcomes are heart-type free fatty acid-binding protein values at 1-2 hours, 6-8 hours and 24 hours postoperatively; the incidence of acute kidney injury within 48 hours postoperatively; the Quality of Recovery-15 score at 24 hours, 48 hours postoperatively; post-anaesthesia care unit length of stay; other postoperative cardiovascular complications; the number of times rescue analgesia and antiemetics are required; the time to first ambulation and length of postoperative hospitalisation.

ETHICS AND DISSEMINATION

This study involves the participation of human subjects and has received approval from the Clinical Trial Ethics Committee at The Affiliated Lianyungang Hospital of Xuzhou Medical University (approval number: KY-20230915001). Study results will be presented at scientific meetings and in scientific publications.

TRIAL REGISTRATION NUMBER

ChiCTR2300077675.

The optimal neoadjuvant treatment strategy for HR+/HER2 + breast cancer: a network meta-analysis

The efficacy of neoadjuvant therapy varies significantly with hormone receptor (HR) status for patients with human epidermal growth factor receptor 2 (HER2) positive breast cancer (BC). Despite extensive research on HER2 + BC, the optimal neoadjuvant strategy for HR+/HER2 + BC remains inconclusive. This study aimed to identify the optimal neoadjuvant regimen for HR+/HER2 + BC treatment. We conducted a systematic search for trials comparing neoadjuvant regimens for HR+/HER2 + BC and a network meta-analysis. Odds ratios for pathological complete response (pCR) and hazard ratios for event-free survival (EFS) were calculated. Treatment regimens were ranked using the surface under the cumulative ranking curve. 20 trials with 2809 patients were included. In pCR analysis, three neoadjuvant regimens sequentially ranked at the top, namely those comprising T-DM1, pertuzumab with trastuzumab, and tyrosine kinase inhibitor with trastuzumab, demonstrating significantly higher pCR rates than monotherapies. In EFS analysis, pertuzumab with trastuzumab ranked the first while T-DM1 containing regimen ranked the last. Anthracycline-free regimens showed a marginally higher pCR rate than anthracycline-containing regimens, while carboplatin-containing regimens demonstrated a numerically higher pCR rate than carboplatin-free regimens. Significant heterogeneity was observed in endocrine therapy analysis, which may be caused by different strategies for incorporating endocrine therapy. In conclusion, trastuzumab plus pertuzumab stands out as the optimal neoadjuvant HER2-targeting regimen for HR+/HER2 + BC Furthermore, anthracycline-free carboplatin-containing chemotherapy emerges as a promising combination treatment. Further investigation is required to clarify the role of endocrine therapy in HR+/HER2 + BC to guide its clinical application.

An exploration of the optimal combination chemotherapy regimen based on neoadjuvant therapy containing pyrotinib for HER2-positive breast cancer: A multicenter real-world study

BACKGROUND

The combination of pyrotinib (Py) with cytotoxic agents proved to be effective in early human epidermal growth factor receptor 2 (HER2)-positive breast cancer (BC). However, the optimal chemotherapy regimen is unknown. This study attempts to explore it from real-world research data.

METHODS

Information was collected from patients with early-stage HER2-positive BC from 23 centers across the country. They were categorized into the anthracycline group (A group) and non-anthracycline group (non-A group). Patients in the non-A group were further categorized into the platinum group and non-platinum group and the short-cycle (≤4 cycles) taxane group and long-cycle (>4 cycles) taxane group. Total pathological complete response (tpCR, ypT0/is ypN0) and breast pathological complete response (bpCR, ypT0/is) rates were assessed.

RESULTS

A total of 107 patients were enrolled. Postoperative pathology indicated a tpCR rate of 36.8 %, a bpCR rate of 42.1 % in the A group, the non-A group had a tpCR rate of 47.8 %, and a bpCR rate of 53.6 %, with P-values of 0.273 and 0.254, respectively. In the long-cycle taxane group, the tpCR and bpCR rates were 60.8 % and 66.7 %, respectively. In the short-cycle taxane group, the tpCR and bpCR rates were 11.1 % and 16.7 %, respectively (both P<0.001). The platinum group had higher tpCR rate (62.9 % vs. 32.4 %, respectively; P = 0.011) and bpCR rate (65.7 % vs. 41.2 %, respectively; P = 0.041).

CONCLUSION

As for a neoadjuvant therapy regimen with Py, an anthracycline-free regimen is feasible. Besides, platinum-containing, long-cycle taxane regimens appear to achieve superior efficacy under anthracycline-removed conditions.

Neoadjuvant atezolizumab in combination with dual HER2 blockade plus epirubicin in women with early HER2-positive breast cancer: the randomized phase 2 ABCSG-52/ATHENE trial

The role of anthracyclines in the treatment of early breast cancer (EBC) is increasingly being challenged, especially in de-escalation strategies. However, owing to their immunogenic effects, anthracyclines are promising combination partners with immunotherapies. In the randomized phase 2 trial ABCSG-52 (EudraCT no. 2019-002364-27), we investigated epirubicin plus immunotherapy in women with human epidermal growth factor receptor 2 (HER2)-positive EBC. A total of 58 patients were randomized 1:1 to two cycles of a chemotherapy-free induction phase (part 1) of dual HER2 blockade with trastuzumab and pertuzumab (TP) plus the anti-programmed death ligand 1 antibody atezolizumab (TP-A) or TP alone. Thereafter, all patients received four cycles of TP-A in combination with epirubicin (part 2). The primary endpoint, pathological complete response (pCR), was met in 35 patients (60.3%; 95% confidence interval (CI) 47.5% to 71.9%), 19 patients (65.5%) in the TP-A group and 16 patients (55.2%) in the TP group. The residual cancer burden 0/I rate and objective response rate (secondary endpoints) in all patients with evaluable data were 80.0% (n = 44/55; 95% CI 67.6% to 88.4%) and 89.3% (n = 50/56; 95% CI 78.5% to 95.0%), respectively. Grade ≥3 adverse events were reported in 17 patients (29.3%). Based on our findings, we conclude that a neoadjuvant chemotherapy de-escalation immunotherapy regimen with trastuzumab, pertuzumab, atezolizumab and epirubicin is effective and safe in patients with HER2-positive EBC.

De-escalated neoadjuvant weekly nab-paclitaxel with trastuzumab and pertuzumab versus docetaxel, carboplatin, trastuzumab, and pertuzumab in patients with HER2-positive early breast cancer (HELEN-006): a multicentre, randomised, phase 3 trial

BACKGROUND

A previous phase 2 trial showed promising outcomes for patients with HER2-positive early-stage breast cancer using neoadjuvant de-escalation chemotherapy with paclitaxel, trastuzumab, and pertuzumab. We aimed to evaluate the efficacy of weekly nab-paclitaxel compared with the standard regimen of docetaxel plus carboplatin, both with trastuzumab and pertuzumab, as neoadjuvant therapies for patients with HER2-positive breast cancer.

METHODS

HELEN-006 was a multicentre, randomised, phase 3 trial done at six hospitals in China. We enrolled patients aged 18-70 years with untreated, histologically confirmed stage II-III invasive HER2-positive breast cancer and an Eastern Cooperative Oncology Group performance status of 0 or 1. Using an interactive response system, patients were randomly assigned (1:1) under a permuted block randomisation scheme (block size of four), stratified by tumour stage, nodal status, and hormone receptor status. Patients received either intravenous nab-paclitaxel (125 mg/m2 on days 1, 8, and 15) for six 3-week cycles, or intravenous docetaxel (75 mg/m2 on day 1) plus intravenous carboplatin (area under the concentration-time curve 6 mg/mL per min on day 1) for six 3-week cycles. Both groups also received concurrent intravenous trastuzumab, with an initial loading dose of 8 mg/kg and a maintenance dose of 6 mg/kg on day 1, as well as intravenous pertuzumab with a loading dose of 840 mg and a maintenance dose of 420 mg on day 1. This report is the final analysis of the primary endpoint, pathological complete response (ypT0/is ypN0), analysed in all patients who started treatment (modified intention to treat). The trial is registered with ClinicalTrials.gov, NCT04547907, and follow-up of the adjuvant phase is ongoing.

FINDINGS

Between Sept 20, 2020, and March 1, 2023, 789 patients were screened for eligibility, 689 of whom were randomly assigned (343 to the nab-paclitaxel group and 346 to the docetaxel plus carboplatin group). All 689 patients were Asian women. 669 patients received at least one dose of the study treatment and were included in the full analysis set (332 in the nab-paclitaxel group and 337 in the docetaxel plus carboplatin group). Median age of the patients was 50 years (IQR 43-55). Median follow-up time was 26 months (IQR 19-32). 220 (66·3% [95% CI 61·2-71·4]) patients in the nab-paclitaxel group had a pathological complete response, compared with 194 (57·6% [52·3-62·9]) in the docetaxel plus carboplatin group (combined odds ratio 1·54 [95% CI 1·10-2·14]; stratified p=0·011). 100 (30%) patients in the nab-paclitaxel group and 128 (38%) in the docetaxel plus carboplatin group had grade 3-4 adverse events. The most common grade 3-4 adverse events were nausea (22 [7%] in the nab-paclitaxel group vs 76 [23%] in the docetaxel plus carboplatin group), diarrhoea (25 [8%] vs 55 [16%]), and neuropathy (43 [13%] vs eight [2%]). Serious drug-related adverse events were reported in three (1%) patients in the nab-paclitaxel group and five (2%) in the docetaxel plus carboplatin group. No treatment-related deaths were reported in either group.

INTERPRETATION

These findings might suggest a potential advantage of nab-paclitaxel combined with trastuzumab and pertuzumab compared with the standard regimen in neoadjuvant therapy for patients with HER2-positive early breast cancer, suggesting that this new combination might establish a new standard for neoadjuvant treatment in this patient population.

FUNDING

National Natural Science Foundation of China, and Science and Technology Research Projects of Henan Province, China.

TRANSLATION

For the Chinese translation of the abstract see Supplementary Materials section.

Unusual Metastatic Lymph Node to Retro-Scapular Area in Occult Breast Cancer: A Case Report

Introduction

Breast cancer typically metastasizes to axillary, internal mammary and supraclavicular lymph node chains. In contrast, occult breast cancer (OBC), a rare form of breast cancer, usually presents as axillary lymphadenopathy and rarely metastasizes regionally or distally.

Case Presentation

In this case report, we present a 45-year-old female patient with unusual presentation of breast cancer initially as axillary lymphadenopathy without breast mass. She was diagnosed by magnetic resonance imaging as OBC and later presented with a rare pathological spread to the ipsilateral subscapular region. The retro-scapular nodal disease was first detected via follow-up computed tomography scan and confirmed by positron emission tomography after 18 months of her initial diagnoses. This occurred following completion of OBC management, which included neoadjuvant chemotherapy, axillary lymph node dissection, without mastectomy, followed by adjuvant radiation treatment to regional lymph nodes and ipsilateral whole breast. Her recurrent nodal disease was subsequently managed by surgical resection followed by radiation therapy to surgical bed.

Conclusion

This case report emphasizes the diverse locations where metastatic breast cancer can manifest and underscores the advancements in diagnostic tools that have enhanced the detection of these metastatic sites.

Incidence of antibody-drug conjugate-related hepatotoxicity in breast cancer: a systematic review and meta-analysis

Background

Antibody-drug conjugates (ADCs), as a new type of targeted drug, have been widely used in breast cancer patients in recent years. However, while achieving better efficacy, its hepatotoxicity should not be ignored.

Objectives

To clarify the incidence of hepatotoxicity associated with ADCs and compare the incidence of hepatotoxicity of ADCs with different drugs.

Design

We performed a systematic review and meta-analysis to summarize the clinical trials and combined the data using meta-analysis.

Methods

We searched the PubMed, Embase, and Web of Science databases up to March 12, 2023. The primary outcome was the incidence of ADC-related hepatotoxicity in breast cancer patients. The data were merged using Stata 17.0 software.

Results

ADCs caused a high incidence of all grades of hepatotoxicity. Sacituzumab govitecan caused the highest incidence of all grades of alanine aminotransferase (ALT) elevation at 25.30% (95% confidence interval (CI): 19.29-31.82). Trastuzumab deruxtecan caused the highest incidence of all grades of aspartate aminotransferase (AST) elevation. The highest incidence of AST elevation was 31.89% (95% CI: 18.56-46.85). Conversely, trastuzumab emtansine caused the highest incidence of grade ⩾3 AST and ALT elevation (incidence rates were 3.95% (95% CI: 2.39-5.85) and 3.42% (95% CI: 1.95-5.24), respectively).

Conclusion

Hepatotoxicity is an adverse reaction that cannot be ignored when ADCs are used for treating breast cancer. Moreover, clinicians should pay more attention to the assessment of patients' liver function and monitoring of liver indices, particularly ALT and AST, when using ADCs.

Interventions for prevention and treatment of trastuzumab-induced cardiotoxicity: an umbrella review of systematic reviews and meta-analyses

Background

Trastuzumab therapy for HER2-positive cancers is associated with cardiotoxicity. This umbrella review synthesizes evidence from systematic reviews and meta-analyses on cardioprotective interventions during trastuzumab treatment.

Methods

A comprehensive search was conducted in PubMed, Embase, Cochrane Library, and Web of Science. Systematic reviews and meta-analyses examining cardioprotective interventions in patients receiving trastuzumab were included. The methodological quality was assessed using the AMSTAR-2 tool. Data on cardiac events, treatment interruptions, left ventricular ejection fraction (LVEF) changes, and exercise interventions were synthesized.

Results

Ten systematic reviews met the inclusion criteria. Statins demonstrated the strongest cardioprotective effect (RR = 0.47, 95% CI: 0.26-0.84), potentially preventing more than half of cardiac events during trastuzumab therapy, followed by beta-blockers (RR = 0.61, 95% CI: 0.39-0.93). Beta-blockers and ACEIs effectively reduced treatment interruptions, enabling approximately 40% more patients to maintain treatment continuity (RR = 0.63, 95% CI: 0.47-0.86). Among non-pharmacological interventions, structured exercise programs showed significant benefits in preserving cardiac function, demonstrating meaningful improvements in resting LVEF (WMD = -3.27%, 95% CI: -5.86 to -0.68).

Discussion

This review demonstrates that cardioprotective interventions, particularly statins and beta-blockers, significantly reduce the risk of cardiac complications during trastuzumab therapy. The positive impact on cardiac events and treatment interruptions suggests these interventions may enhance overall treatment efficacy by allowing more patients to complete their prescribed course.

Conclusion

Evidence strongly supports the systematic implementation of cardioprotective strategies in clinical practice, particularly statins and beta-blockers, as part of routine care protocols for patients receiving trastuzumab therapy. These interventions demonstrate significant potential in preventing cardiac complications and maintaining treatment continuity. Further research should focus on optimizing personalized approaches and evaluating long-term outcomes.

Dual HER2 inhibition: mechanisms of synergy, patient selection, and resistance

HER2-targeted therapies for patients with HER2+ breast cancer are rapidly evolving, offering a range of more complex and personalized treatment options. Currently, an array of anti-HER2 monoclonal antibodies, tyrosine kinase inhibitors and antibody-drug conjugates are administered, sometimes alongside chemotherapy or endocrine therapy, both in curative and palliative contexts. However, the heterogeneous nature of HER2+ breast cancer demands a deeper understanding of disease biology and its role in responsiveness to novel HER2-targeted agents, as well as non-HER2-targeted therapies, in order to optimize patient outcomes. In this Review, we revisit the mechanisms of action of HER2-targeted agents, examine the evidence supporting the use of dual HER2 blockade in patients with HER2-amplified tumours, and explore the role of biomarkers in guiding future treatment strategies. We also discuss potential implications for the future treatment of patients with HER2+ breast cancer.

Effect of Estrogen Receptor on the Relationship Between HER2 Immunohistochemistry Score and Pathological Complete Response to Neoadjuvant Treatment in HER2-Positive Breast Cancer

Purpose: We aimed to investigate whether estrogen receptor (ER) status affects the predictive role of the human epidermal growth factor receptor 2 (HER2) immunohistochemistry (IHC) score on the efficacy of neoadjuvant treatment for HER2-positive breast cancer. Methods: This retrospective study comprised 167 individuals diagnosed with HER2-positive invasive breast cancer who had undergone neoadjuvant treatment and surgery. Uni- and multivariable logistic regression analyses were performed on the relationship between the HER2 IHC score and total pathological complete response (tpCR), breast pathological complete response (bpCR), or axillary partial response (apCR). Subgroup analyses were used to investigate whether the relationship between the HER2 IHC score and tpCR, bpCR, or apCR differed by ER or PR status. Results: The overall tpCR rate for HER2-positive breast cancers treated with neoadjuvant treatment was 41.32% (69 of 167). The tpCR, bpCR, and apCR rates were greater in the HER2 IHC 3+ group (tpCR: IHC 3 + 47.69% vs. IHC 2 + 18.92%, p=0.009). Significant interactions between HER2 IHC score and tpCR or bpCR were found in subgroup analyses based on ER status (tpCR: p for interaction = 0.001; bpCR: p for interaction = 0.001). Among ER-positive patients, the HER2 IHC 2+ group had substantially decreased tpCR, bpCR, and apCR rates than the HER2 IHC 3+ group (tpCR rate: p=0.003; bpCR rate: p=0.002; apCR rate: p=0.002). For ER-negative individuals, the tpCR, bpCR, and apCR rates did not differ significantly among the HER2 IHC 3+ versus HER2 IHC 2+ groups. Similarly, interactions between HER2 IHC score and tpCR, bpCR, or apCR were found in subgroup analyses based on PR status. Conclusion: HER2 IHC 2+ may indicate a decreased tpCR rate, bpCR rate, and apCR rate to neoadjuvant treatment in HR-positive patients having HER2-positive breast cancer, but not in HR-negative patients.

Cardiac toxicity of HER-2 targeting antibody-drug conjugates: overview and clinical implications

Antibody-drug conjugates (ADCs) have recently emerged as a promising therapeutic option that combine the specificity of monoclonal antibodies and the cytotoxic effect of chemotherapy. With numerous ADCs approved and on the market, a particular concern of ADCs that target HER-2 has been their cardiac side effects, in view of the crucial role of HER-2 in cardiac development and physiology. While rarely toxic and generally safe, numerous publications have outlined the consistent association of trastuzumab emtansine (T-DM1) and trastuzumab deruxtecan (T-DXd) with the development of cardiac toxicity. Despite not being clinically relevant in most cases, cardiac baseline evaluation, monitoring and early detection of cardiac adverse events remain pivotal with HER-2 targeting ADCs. This review aims to summarize and better characterize the complete cardiac toxicity profile of HER-2 ADCs, with the goal of improving clinical understanding of this adverse event, leading to better recognition, monitoring and management.

Comprehensive Axillary Management of Clinically Node-Positive (cN+) Breast Cancer Patients: A Narrative Review on Neoadjuvant Chemotherapy

BACKGROUND

In breast cancer (BC) patients, axillary management has undergone major improvements over the last few years, and efforts to identify the optimal strategy for the management of axillary surgery are still ongoing.

METHODS

In current clinical practice, women with clinically node-positive (cN+) BC usually receive neoadjuvant chemotherapy (NACT) with the aim of reducing the extent of primary disease and, thus, allowing for axillary-conservative surgery. Remarkably, after NACT, up to one out of three patients achieves an axillary pathologic complete response, which, in turn, is associated with a more favorable prognosis than residual axillary disease. However, NACT is not without drawbacks, as NACT-associated inflammation can damage lymphatic vessels. Furthermore, varying degrees of response may occur in the axillary lymph nodes, increasing the false negative rate for sentinel biopsy.

RESULTS

At present, there is no consensus on the optimal approach in patients with cN+ BC undergoing NACT, although multidisciplinary management seems to be recommended.

CONCLUSIONS

This narrative review provides a comprehensive overview of axillary management in cN+ BC patients undergoing NACT. It uses a multidisciplinary approach that encompasses the oncological management perspectives, as well as surgical and chemotherapeutic viewpoints.

Shifting the Paradigm: The Transformative Role of Neoadjuvant Therapy in Early Breast Cancer

The use of neoadjuvant systemic therapy (NST) has become increasingly important in the treatment of breast cancer because of its various advantages. These include the ability to downstage tumors without compromising locoregional control and the potential to obtain valuable information about clinical and biological response to therapy with implications for individual prognoses. Surgical response assessment paves the way for response-adapted therapy, and pathological complete response (pCR; defined as ypT0/is ypN0) serves as an additional endpoint for drug development trials. Recommended NST regimens commonly consist of anthracyclines and taxane, with dose-dense anthracyclines and weekly paclitaxel often preferred, whenever feasible. For patients with human epidermal growth factor receptor-2 (HER2)-positive tumors, dual anti-HER2 therapy (trastuzumab and pertuzumab) is indicated together with NST in case of elevated risk of recurrence. For patients with triple-negative breast cancer (TNBC), adding carboplatin to NST correlates with improved pCR and survival rates, as does the addition of immune checkpoint inhibitors. For hormone receptor (HR)-positive/HER2-negative cancers, emerging data on NST including immune checkpoint inhibitors may elevate the significance of NST in high-risk luminal breast cancer. Here, we present a synthesis of the results from neoadjuvant clinical trials that aim at optimizing treatment options for patients with high-risk breast cancer.

Antibody drug conjugates in recurrent or metastatic cervical cancer: a focus on tisotumab vedotin state of art

Cervical cancer (CC) is still characterized by a poor prognosis despite the progress made in its treatment in recent years. Although immunotherapy has improved outcomes for advanced/recurrent disease, there is a significant gap in addressing patients' needs when they progress after platinum and immunotherapy treatments. In this setting, traditional chemotherapy showed limited effectiveness. In this context, antibody-drug conjugates (ADCs) emerged as a promising tool within targeted cancer therapies. Tisotumab vedotin (TV), an ADC targeting tissue factor, represents the first ADC approved by the US Food and Drug Administration for the treatment of recurrent or metastatic CC with disease progression on or after chemotherapy. In phase I-III published trials, TV has already demonstrated an advantage in terms of objective response rate (17.8%-54.4%) and progression-free survival (3.1-6.9 months) in patients who progressed to the first-line standard therapy. Data concerning the addition of TV to platinum/pembrolizumab first-line chemotherapy are still under analysis and strongly expected. However, several questions are still unresolved: (1) the identification of the most suitable timing for ADCs administration in the treatment sequence of advanced/recurrent CC; (2) the evaluation of combination therapies as a tool to minimize the emergence of resistant clones and to enhance overall effectiveness; and (3) the assessment of tolerability and correct management of special toxicities (e.g. ocular and neurological adverse events). In the near future, an improvement in patient selection via biomarker-driven strategies should be crucial for optimizing both treatment benefits and maintaining an acceptable toxicity profile.

HER2-targeted therapies for HER2-positive early-stage breast cancer: present and future

Breast cancer (BC) has the second highest incidence among cancers and is the leading cause of death among women worldwide. The human epidermal growth factor receptor 2 (HER2) is overexpressed in approximately 20%-30% of BC patients. The development of HER2-targeted drugs, including monoclonal antibodies (mAbs), tyrosine kinase inhibitors (TKIs) and antibody-drug conjugates (ADCs), has improved the operation rate and pathological remission rate and reduced the risk of postoperative recurrence for HER2-positive early-stage BC (HER2+ EBC) patients. This review systematically summarizes the mechanisms, resistance, therapeutic modalities and safety of HER2-targeted drugs and helps us further understand these drugs and their use in clinical practice for patients with HER2+ EBC.

Unveiling Neoadjuvant Therapy: Insights and Outlooks for HER2-Positive Early Breast Cancer

OPINION STATEMENT

This perspective underscores the evolution and significance of neoadjuvant therapy in breast cancer, tracing its history and efficacy in improving outcomes. It delves into the correlation between achieving complete response and long-term survival, emphasizing the predictive value of treatment response estimation. Neoadjuvant chemotherapy in HER2-positive early breast cancer, particularly with taxanes and anti-HER2 therapies, emerges as a cornerstone, offering enhanced breast conservation rates and prognostic insights. The focus on individualized care, tailored to treatment response, underscores the need for adaptive strategies. Additionally, the article discusses the ongoing debate surrounding anthracyclines' role and the benefits of dual HER2 blockade. Ultimately, advocating for a personalized approach, guided by treatment response assessment, ensures optimal outcomes in HER2-positive breast cancer management.

Targeted multimodal synergistic therapy of drug-resistant HER2-positive breast cancer by pyrotinib-ICG self-assembled nanoparticles

Neoadjuvant targeted therapy combining targeted agents with chemotherapy significantly improve survival rates of patients suffering from human epidermal receptor (HER2)-positive breast cancer (BC) in early or locally advanced stages. However, approximately 50% of patients fail to achieve a pathological complete response. In response, targeted photothermal therapy (PTT) and photodynamic therapy (PDT) have emerged as effective strategies to bolster primary tumors treatment. In this context, we developed a novel nanodrug, referred to as "P/ICG", which comprised of a tyrosine-kinase inhibitor pyrotinib and the photosensitizer indocyanine green (ICG). This formulation was created for the targeted and multimodal synergistic therapy of HER2-positive BC. Upon irradiation with near-infrared light, ICG generates high levels of intracellular reactive oxygen species and elevated temperature, enhancing chemotherapy effects of pyrotinib. This synergistic action boosts a highly effective anticancer effect promoting the ferroptosis pathway, providing an efficient therapeutic strategy for treating HER2-positive BC.

Trastuzumab-Induced Cardiotoxicity: When and How Much Should We Worry?

This review critically analyzes the incidence of trastuzumab-induced left ventricular systolic dysfunction and congestive heart failure (CHF), distinguishing between cases with and without prior anthracycline exposure. It highlights the fact that the elevated risk of trastuzumab-induced cardiotoxicity is closely associated with prior anthracycline exposure. In the absence of prior anthracycline exposure, the incidence rates of trastuzumab-induced cardiotoxicity, particularly CHF (ranging from 0% to 0.5%), are largely comparable with those reported in the general population, especially when reversibility is taken into account. Current cardiac surveillance recommendations during trastuzumab treatment have not yet adapted to the increasing adoption of nonanthracycline treatment strategies and the associated low risk of cardiotoxicity. We propose a refined monitoring protocol to reduce the frequency of cardiac evaluations for low-risk to moderate-risk patients, especially those receiving nonanthracycline treatments. By focusing on patients at high risk or those with prior anthracycline exposure, this strategy seeks to optimize the cost-effectiveness of cardiac care in oncology.

Long-term outcomes of neoadjuvant trastuzumab emtansine + pertuzumab (T-DM1 + P) and docetaxel + carboplatin + trastuzumab + pertuzumab (TCbHP) for HER2-positive primary breast cancer: results of the randomized phase 2 JBCRG20 study (Neo-peaks)

PURPOSE

The randomized phase 2 Neo-peaks study examined usefulness of neoadjuvant trastuzumab emtansine + pertuzumab (T-DM1 + P) following docetaxel + carboplatin + trastuzumab + pertuzumab (TCbHP) as compared with the standard TCbHP regimen. We previously reported that pCR rate after neoadjuvant therapy tended to be higher with TCbHP followed by T-DM1 + P. We conducted an exploratory analysis of prognosis 5 years after surgery.

METHODS

Neoadjuvant treatment with TCbHP (6 cycles; group A), TCbHP (4 cycles) followed by T-DM1 + P (4 cycles; group B), and T-DM1 + P (4 cycles; group C, + 2 cycles in responders) were compared. Group C non-responders after 4 cycles were switched to an anthracycline-based regimen. We evaluated 5-year disease-free survival (DFS), distant DFS (DDFS), and overall survival (OS).

RESULTS

Data from 203 patients (50, 52, and 101 in groups A-C, respectively) were analyzed. No significant intergroup differences were found for DFS, DDFS, or OS. The 5-year DFS rates (95% CI) were 91.8% (79.6-96.8%), 92.3% (80.8-97.0%), and 88.0% (79.9-93.0%) in groups A-C, respectively. TCbHP followed by T-DM1 + P and T-DM1 + P with response-guided addition of anthracycline therapy resulted in similar long-term prognosis to that of TCbHP.

CONCLUSIONS

In patients who achieved pCR after neoadjuvant therapy with T-DM1 + P, omission of adjuvant anthracycline may be considered, whereas treatment should be adjusted for non-pCR patients with residual disease. T-DM1 + P with response-guided treatment adjustment may be useful for minimizing toxicity.

TRIAL REGISTRATION NUMBER AND DATE OF REGISTRATION

UMIN-CTR, UMIN000014649, prospectively registered July 25, 2014. Some of the study results were presented as a Mini Oral session at the ESMO Breast Cancer 2023 (Berlin, Germany, 11-13 May 2023).

Antibody-drug conjugates in cancer therapy: mechanisms and clinical studies

Antibody-drug conjugates (ADCs) consist of monoclonal antibodies that target tumor cells and cytotoxic drugs linked through linkers. By leveraging antibodies' targeting properties, ADCs deliver cytotoxic drugs into tumor cells via endocytosis after identifying the tumor antigen. This precise method aims to kill tumor cells selectively while minimizing harm to normal cells, offering safe and effective therapeutic benefits. Recent years have seen significant progress in antitumor treatment with ADC development, providing patients with new and potent treatment options. With over 300 ADCs explored for various tumor indications and some already approved for clinical use, challenges such as resistance due to factors like antigen expression, ADC processing, and payload have emerged. This review aims to outline the history of ADC development, their structure, mechanism of action, recent composition advancements, target selection, completed and ongoing clinical trials, resistance mechanisms, and intervention strategies. Additionally, it will delve into the potential of ADCs with novel markers, linkers, payloads, and innovative action mechanisms to enhance cancer treatment options. The evolution of ADCs has also led to the emergence of combination therapy as a new therapeutic approach to improve drug efficacy.

Neoadjuvant inetetamab and pertuzumab with taxanes and carboplatin (TCbIP) In locally advanced HER2-positive breast cancer: a prospective cohort study with propensity-matched analysis

BACKGROUND

Inetetamab is the first domestically developed innovative anti-HER2 monoclonal antibody in China, proven effective and safe in HER2-positive advanced breast cancer. However, its efficacy and safety in neoadjuvant treatment of HER2-positive locally advanced breast cancer (LABC) remain to be validated.

METHODS

This prospective cohort study aimed to evaluate the efficacy and safety of inetetamab combined with pertuzumab, taxanes, and carboplatin (TCbIP) in neoadjuvant therapy for HER2-positive LABC, comparing it to data from patients treated with the TCbHP regimen (trastuzumab combined with pertuzumab, taxanes, and carboplatin) using propensity score matching (PSM). The primary endpoint was total pathological complete response (tpCR). Adverse events (AEs), objective response rate (ORR), and near-pCR were key secondary endpoints.

RESULTS

Forty-four patients with clinical stage IIA-IIIC HER2-positive LABC were prospectively enrolled and treated with the TCbIP regimen. The tpCR rate among 28 patients who completed surgery was 60.7%, comparable to and slightly higher than the TCbHP group in PSM (60.7% vs. 53.6%, P = 0.510). The ORR was 96.4%, and the DCR reached 100.0%. The most common ≥ grade 3 AE was neutropenia (21.4% vs. 11.9%, P = 0.350). No significant reduction in left ventricular ejection fraction was observed, and no patient withdrew from treatment due to AEs.

CONCLUSION

Neoadjuvant therapy with TCbIP showed good efficacy and safety in patients with HER2-positive LABC and might be another promising option for neoadjuvant treatment.

TRIAL REGISTRATION

NCT05749016 (registration date: Nov 01, 2021).

Cost-utility and budget impact analysis of neoadjuvant dual HER2 targeted therapy for HER2-positive breast cancer in Sri Lanka

This study aimed to assess the cost-utility and budget impact of dual to single HER2 targeted neoadjuvant therapy for HER2-positive breast cancer in Sri Lanka. A five-health state Markov model with lifetime horizon was used to assess the cost-utility of neoadjuvant trastuzumab (T) plus pertuzumab (P) or lapatinib (L) compared to single therapy of T with chemotherapy (C), in public healthcare system and societal perspectives. Input parameters were estimated using local data, network meta-analysis, published reports and literature. Costs were adjusted to year 2021 (1USD = LKR194.78). Five-year budget impact for public healthcare system was assessed. Incremental cost-effectiveness ratios in societal perspective for neoadjuvantLTC plus adjuvantT (strategy 3), neoadjuvantPTC plus adjuvantT (strategy 2), neoadjuvantLTC plus adjuvantLT (strategy 5), and neoadjuvantPTC plus adjuvantPT (strategy 4) compared to neoadjuvantTC plus adjuvantT (strategy 1) were USD2716, USD5600, USD6878, and USD12127 per QALY gained, respectively. One GDP per-capita (USD3815) was considered as the cost-effectiveness threshold for the analysis. Even though only the ICER for strategy 3 was cost-effective, uncertainty of efficacy parameter was revealed. For strategy 2 neoadjuvant PTC plus adjuvant T, a 25% reduction of neoadjuvant regimen cost was required to be cost effective for use in early HER2 positive breast cancer.

Spotlight on ideal target antigens and resistance in antibody-drug conjugates: Strategies for competitive advancement

Antibody-drug conjugates (ADCs) represent a novel and promising approach in targeted therapy, uniting the specificity of antibodies that recognize specific antigens with payloads, all connected by the stable linker. These conjugates combine the best targeted and cytotoxic therapies, offering the killing effect of precisely targeting specific antigens and the potent cell-killing power of small molecule drugs. The targeted approach minimizes the off-target toxicities associated with the payloads and broadens the therapeutic window, enhancing the efficacy and safety profile of cancer treatments. Within precision oncology, ADCs have garnered significant attention as a cutting-edge research area and have been approved to treat a range of malignant tumors. Correspondingly, the issue of resistance to ADCs has gradually come to the fore. Any dysfunction in the steps leading to the ADCs' action within tumor cells can lead to the development of resistance. A deeper understanding of resistance mechanisms may be crucial for developing novel ADCs and exploring combination therapy strategies, which could further enhance the clinical efficacy of ADCs in cancer treatment. This review outlines the brief historical development and mechanism of ADCs and discusses the impact of their key components on the activity of ADCs. Furthermore, it provides a detailed account of the application of ADCs with various target antigens in cancer therapy, the categorization of potential resistance mechanisms, and the current state of combination therapies. Looking forward, breakthroughs in overcoming technical barriers, selecting differentiated target antigens, and enhancing resistance management and combination therapy strategies will broaden the therapeutic indications for ADCs. These progresses are anticipated to advance cancer treatment and yield benefits for patients.

In situ HER2 RNA expression as a predictor of pathologic complete response of HER2-positive breast cancer patients receiving neoadjuvant chemotherapy and anti-HER2 targeted treatment

BACKGROUND

Immunohistochemistry (IHC) and in situ hybridization (ISH) remain standard biomarkers for therapeutic decisions in human epidermal growth factor 2 (HER2)-positive breast cancers (BCs); however, they are insufficient to explain the heterogeneous anti-HER2 response.

METHODS

We aimed to investigate the correlation of in situ HER2 RNA expression (isHRE), using RNAscope, with HER2 biomarkers and the impact of isHRE on the pathological complete response (pCR) rates of 278 patients with HER2 IHC/fluorescence ISH (FISH)-positive BC receiving neoadjuvant chemotherapy and anti-HER2 targeted treatment (NCTT).

RESULTS

We validated HER2 RNAscope scoring as a semiquantitative method to determine isHRE and showed a positive correlation between RNAscope scores and pCR rates, with particularly different rates between patients with a score of 5 versus 1-4 BCs (66.7% vs. 15.9%, p < 0.0001). There were higher RNAscope scores and pCR rates in patients with HER2 IHC 3 + versus IHC 2+/FISH + BCs and HER2 RNAscope scores and pCR rates showed similar non-linear positive correlations with HER2 copy numbers and HER2/centromere 17 ratios. Moreover, in each HER2-positive IHC/FISH category, higher pCR rates were observed in patients with RNAscope scores of 5 versus 1-4 BC. Patients achieving pCR had BCs with notably higher HER2 RNAscope scores. Multivariate analysis identified HER2 RNAscope 5 as a strong pCR predictor [odds ratio = 10.865, p < 0.001]. The combined impact of multivariate analysis-defined pCR predictors demonstrated that a higher pCR rate was observed in patients with a score of 5 versus a score of 1-4 BCs regardless of the status of hormone receptor and mono-or dual anti-HER2 blockade.

CONCUSIONS

Our results demonstrated that high isHRE (RNAscope score 5) is a strong pCR predictor in patients with HER2-positive BCs receiving NCTT, highlighting the complementary role of isHRE in stratifying HER2 status in tissue. Such stratification is relevant to anti-HER2 therapeutic efficacy, particularly using the cutoff of score 1-4 versus 5.

Mechanisms of action and resistance to anti-HER2 antibody-drug conjugates in breast cancer

Human epidermal growth factor 2 (HER2)-positive breast cancer (BC) represents nearly 20% of all breast tumors. Historically, these patients had a high rate of relapse and dismal prognosis. The advent of HER2-targeting monoclonal antibodies such as trastuzumab followed by pertuzumab had improved the prognosis of HER2-positive metastatic BC. More recently, antibody-drug conjugates (ADCs) are now reshaping the treatment paradigm of solid tumors, especially breast cancer. Tratsuzumab emtansine (T-DM1) was one of the first ADC developed in oncology and was approved for the management of HER2-positive metastatic BC. In a head-to-head comparison, trastuzumab deruxtecan (T-DXd) defeated T-DM1 as a second-line treatment. The efficacy of ADCs is counterbalanced by the appearance of acquired resistance to these agents. In this paper, we summarize the mechanisms of action and resistance of T-DM1 and T-DXd, as well as their clinical efficacy. Additionally, we also discuss potential strategies for addressing resistance to ADC.

Comparison of anthracycline-containing and anthracycline-free regimens in neoadjuvant HER-2 positive breast cancer treatment

While some clinics have adopted abbreviated neoadjuvant treatment for HER2-positive breast cancer, there remains a shortage of comprehensive clinical data to support this practice. This is a retrospective, multicenter study. A total of 142 patients were included in the study who are HER2-positive breast cancer, aged ≤ 65 years, with left ventricular ejection fraction ≥ 50%, received neoadjuvant chemotherapy and underwent surgery at 10 different oncology centers in Türkiye between October 2016 and December 2022. The treatment arms were divided into 4-6 cycles of docetaxel/trastuzumab/pertuzumab for arm A, 4 cycles of adriamycin/cyclophosphamide followed by 4 cycles of taxane/TP for arm B. There were 50 patients (35.2%) in arm A and 92 patients (64.8%) in arm B. The median follow-up of all of the patients was 19.9 months (95% CI 17.5-22.3). The 3-year DFS rates for treatment arms A and B were 90.0% and 83.8%, respectively, and the survival outcomes between the groups were similar (p = 0.34). Furthermore, the pathologic complete response rates were similar in both treatment arms, at 50.0% and 51.1%, respectively (p = 0.90). This study supports shortened neoadjuvant treatment of HER2-positive breast cancer, a common practice in some clinics.