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.

Overall Survival with Pembrolizumab in Early-Stage Triple-Negative Breast Cancer.

BACKGROUND: In patients with early-stage triple-negative breast cancer, the phase 3 KEYNOTE-522 trial showed significant improvements in pathological complete response and event-free survival with the addition of pembrolizumab to platinum-containing chemotherapy. Here we report the final results for overall survival. METHODS: We randomly assigned, in a 2:1 ratio, patients with previously untreated stage II or III triple-negative breast cancer to receive neoadjuvant therapy with four cycles of pembrolizumab (at a dose of 200 mg) or placebo every 3 weeks plus paclitaxel and carboplatin, followed by four cycles of pembrolizumab or placebo plus doxorubicin-cyclophosphamide or epirubicin-cyclophosphamide. After definitive surgery, patients received adjuvant pembrolizumab (pembrolizumab-chemotherapy group) or placebo (placebo-chemotherapy group) every 3 weeks for up to nine cycles. The primary end points were pathological complete response and event-free survival. Overall survival was a secondary end point. RESULTS: Of the 1174 patients who underwent randomization, 784 were assigned to the pembrolizumab-chemotherapy group and 390 to the placebo-chemotherapy group. At the data-cutoff date (March 22, 2024), the median follow-up was 75.1 months (range, 65.9 to 84.0). The estimated overall survival at 60 months was 86.6% (95% confidence interval [CI], 84.0 to 88.8) in the pembrolizumab-chemotherapy group, as compared with 81.7% (95% CI, 77.5 to 85.2) in the placebo-chemotherapy group (P = 0.002). Adverse events were consistent with the established safety profiles of pembrolizumab and chemotherapy. CONCLUSIONS: Neoadjuvant pembrolizumab plus chemotherapy followed by adjuvant pembrolizumab resulted in a significant improvement, as compared with neoadjuvant chemotherapy alone, in overall survival among patients with early-stage triple-negative breast cancer. (Funded by Merck Sharp and Dohme, a subsidiary of Merck [Rahway, NJ]; KEYNOTE-522 ClinicalTrials.gov number, NCT03036488.).

A plain language summary of the CAPItello-291 study: Capivasertib in hormone receptor-positive advanced breast cancer.

WHAT IS THIS SUMMARY ABOUT?: This is a summary of the article discussing the results of the CAPItello-291 study. In the study, participants had advanced breast cancer that could not be completely removed with surgery, and that was diagnosed as a type of breast cancer where tumor cells had hormone receptors (HR-positive) but did not have HER2 receptors (HER2-negative). All participants were also required to have previously received treatment with a type of therapy called an aromatase inhibitor (with or without a CDK4/6 inhibitor), but over time their cancer cells had still grown or spread. The CAPItello-291 study researchers wanted to find out if a treatment combination of the medications capivasertib plus fulvestrant worked better than placebo plus fulvestrant. Capivasertib is a drug that blocks the activity of a protein called AKT, which is found inside breast cancer cells. WHAT ARE THE KEY TAKEAWAYS?: The main finding was that participants who took capivasertib plus fulvestrant lived longer without their disease getting worse (progressing) compared with those treated with placebo plus fulvestrant. This is called progression-free survival. This result was seen across all participants (median progression-free survival of 7.2 months with capivasertib plus fulvestrant vs 3.6 months with placebo plus fulvestrant). It was also seen in participants whose tumors had detectable genetic alterations in genes called PIK3CA, AKT1, and/ or PTEN (median progression-free survival of 7.3 months with capivasertib plus fulvestrant vs 3.1 months with placebo plus fulvestrant). The most common side effects experienced by participants included diarrhea and different types of rash. These were as expected (given how capivasertib works). The CAPItello-291 study is still ongoing, and more results are expected to be released in the future. WHAT WERE THE MAIN CONCLUSIONS REPORTED BY THE RESEARCHERS?: Results from the CAPItello-291 study showed that capivasertib plus fulvestrant compared with placebo plus fulvestrant improved progression-free survival in participants with HR-positive/ HER2-negative advanced breast cancer whose cancer had grown or spread despite hormone therapy (with/without a CDK4/6 inhibitor).Clinical Trial Registration: NCT04305496 (CAPItello-291) (ClinicalTrials.gov).

Single-cell RNA sequencing in endometrial cancer: exploring the epithelial cells and the microenvironment landscape.

Single-cell RNA sequencing (scRNA-seq) technology has emerged as a powerful tool for dissecting cellular heterogeneity and understanding the intricate biology of diseases, including cancer. Endometrial cancer (EC) stands out as the most prevalent gynecological malignancy in Europe and the second most diagnosed worldwide, yet its cellular complexity remains poorly understood. In this review, we explore the contributions of scRNA-seq studies to shed light on the tumor cells and cellular landscape of EC. We discuss the diverse tumoral and microenvironmental populations identified through scRNA-seq, highlighting the implications for understanding disease progression. Furthermore, we address potential limitations inherent in scRNA-seq studies, such as technical biases and sample size constraints, emphasizing the need for larger-scale research encompassing a broader spectrum of EC histological subtypes. Notably, a significant proportion of scRNA-seq analyses have focused on primary endometrioid carcinoma tumors, underscoring the need to incorporate additional histological and aggressive types to comprehensively capture the heterogeneity of EC. By critically evaluating the current state of scRNA-seq research in EC, this review underscores the importance of advancing towards more comprehensive studies to accelerate our understanding of this complex disease.

Results from the randomized KEYNOTE-355 study of pembrolizumab plus chemotherapy for Asian patients with advanced TNBC.

In the phase 3 KEYNOTE-355 study (NCT02819518), pembrolizumab plus chemotherapy demonstrated statistically significant and clinically meaningful improvements in progression-free survival (PFS) and overall survival (OS) versus placebo plus chemotherapy among patients with previously untreated locally recurrent inoperable or metastatic triple-negative breast cancer (TNBC) and programmed cell death ligand 1 (PD-L1) combined positive score (CPS) ≥ 10 tumors. We analyzed outcomes for the subgroup of patients enrolled in Asia in KEYNOTE-355. Patients received pembrolizumab 200 mg or placebo (2:1 randomization) every 3 weeks for 35 cycles plus investigator's choice chemotherapy. Primary endpoints were PFS per Response Evaluation Criteria in Solid Tumors version 1.1 and OS. Among patients enrolled in Hong Kong, Japan, Korea, Malaysia and Taiwan (pembrolizumab plus chemotherapy, n = 113; placebo plus chemotherapy, n = 47), 117 (73.1%) had PD-L1 CPS ≥ 1 and 56 (35.0%) had PD-L1 CPS ≥ 10. Median time from randomization to data cutoff (June 15, 2021) was 43.8 (range, 36.8‒53.2) months (intent-to-treat [ITT] population). Hazard ratios (HRs [95% CI]) for PFS in the CPS ≥ 10, CPS ≥ 1, and ITT populations were 0.48 (0.24‒0.98), 0.58 (0.37‒0.91), and 0.66 (0.44‒0.99), respectively. Corresponding HRs (95% CI) for OS were 0.54 (0.28‒1.04), 0.62 (0.40‒0.97), and 0.57 (0.39‒0.84). Grade 3/4 treatment-related adverse events (AEs) occurred in 77.9% versus 78.7% of patients with pembrolizumab plus chemotherapy versus placebo plus chemotherapy. No grade 5 AEs occurred. Clinically meaningful improvement in PFS and OS with manageable toxicity were observed with pembrolizumab plus chemotherapy versus placebo plus chemotherapy in patients enrolled in Asia with previously untreated, inoperable or metastatic TNBC.Trial registration: ClinicalTrials.gov, NCT02819518.

The DEBBRAH trial: Trastuzumab deruxtecan in HER2-positive and HER2-low breast cancer patients with leptomeningeal carcinomatosis.

BACKGROUND: Leptomeningeal disease (LMD) is associated with poor survival and diminished quality of life. Trastuzumab deruxtecan (T-DXd) has shown remarkable intracranial and extracranial activity in human epidermal growth factor receptor 2 (HER2)-positive and HER2-low advanced breast cancer (ABC). The DEBBRAH trial was designed to evaluate its efficacy and safety in patients with HER2-positive and HER2-low ABC with a history of brain metastases (BMs) and/or LMD. Here, we report results from cohort 5, which specifically included patients with pathologically confirmed LMD. METHODS: This single-arm, open-label, five-cohort, phase 2 trial enrolled seven patients in cohort 5 who received 5.4 mg/kg T-DXd intravenously every 21 days until disease progression or unacceptable toxicity. The primary endpoint was overall survival (OS). Key secondary endpoints included progression-free survival (PFS) and safety profile. FINDINGS: At data cutoff (April 4, 2023), the median duration of follow-up was 12.0 months (range, 2.5-18.6). The median OS was 13.3 months (95% confidence interval [CI], 5.7-NA, p < 0.001), meeting the primary endpoint. The median PFS was 8.9 months (95% CI, 2.1-NA). Two (28.6%) of seven patients remained on treatment after 18.6 and 11.9 months, respectively. Of the five patients who progressed and died, none had intracranial progression or clinical worsening of leptomeningeal symptoms. Notably, 71.4% (95% CI, 29.0-96.3) achieved prolonged stabilization (≥24 weeks) by response evaluation criteria in solid tumors (RECIST) v.1.1. No unexpected safety signals and no treatment-related deaths were observed. CONCLUSIONS: T-DXd showed promising antitumor activity in patients with HER2-positive and HER2-low ABC with previously untreated, pathologically confirmed LMD. These encouraging data warrant further investigation to address the unmet need in this difficult-to-treat condition. FUNDING: This work was funded by Daiichi Sankyo/AstraZeneca. This trial is registered with ClinicalTrials.gov: NCT04420598.

High mechanical conditioning by tumor extracellular matrix stiffness is a predictive biomarker for anti-fibrotic therapy in HER2-negative breast cancer.

BACKGROUND: Tumor progression has been linked to stiffening of the extracellular matrix (ECM) caused by fibrosis. Cancer cells can be mechanically conditioned by stiff ECM, exhibiting a 1004-gene signature (MeCo score). Nintedanib has demonstrated anti-fibrotic activity in idiopathic pulmonary fibrosis. This study explores nintedanib's anti-fibrotic effect on breast cancer outcomes. METHODS: We present long-term follow-up and analysis of a neoadjuvant randomized Phase 2 trial in early HER2-negative breast cancer. Patients (N = 130) underwent a baseline biopsy and received 12 paclitaxel courses alone (control arm) or in combination with nintedanib (experimental arm). Tumor MeCo score was determined by RNAseq. The primary aim was to assess nintedanib's impact on event-free survival (EFS) based on MeCo scores. RESULTS: Follow-up data were retrieved from 111 patients; 75 baseline and 24 post-run-in phase samples were sequenced. After median follow-up of 9.67 years, median EFS was not statistically different between arms (P = 0.37). However, in the control arm, High versus Low MeCo patients had a statistically higher relapse risk: hazard ratio (HR) = 0.21; P = 0.0075. This risk was corrected by nintedanib in the experimental arm: HR = 0.37; P = 0.16. Nintedanib demonstrated pharmacodynamic engagement, reducing the MeCo score by 25% during the run-in phase (P<0.01). Patients with Low MeCo after run-in had the best long-term prognosis (HR = 0.087; P = 0.03). CONCLUSIONS: High MeCo is predictive of poor outcomes in HER2-negative early breast cancer, although this risk can be mitigated by nintedanib, which is able to specifically reduce mechanical conditioning.

Sacituzumab govitecan for hormone receptor-positive HER2-negative advanced breast cancer.

INTRODUCTION: Initial treatment for hormone-receptor positive (HR+)/human epidermal growth factor receptor 2 negative (HER2-) advanced breast cancer (ABC) typically involves endocrine therapy (ET) combined with different targeted agents. When hormonal therapies fail, until recently, the only option available was chemotherapy (ChT), presenting a significant therapeutic challenge. However, the recent introduction of antibody-drug conjugates (ADCs) has provided new treatment alternatives in this context. Sacituzumab govitecan (SG), a novel trophoblast cell-surface antigen 2 (Trop-2)-targeting ADC, has been evaluated following disease progression to ET and ChT in HR+/HER2- ABC. AREAS COVERED: This review examines the latest clinical trials, including phase I/II and III studies and evaluates the impact of SG on HR+/HER2- ABC. The literature search focused on clinical outcomes, particularly regarding efficacy and safety, comparing them with traditional ChT. EXPERT OPINION: SG has demonstrated to be an effective treatment for patients with HR+/HER2- ABC after progression to ET and cyclin-dependent kinase 4/6 inhibitors (CDKi) in any setting, and at least two ChT-containing regimens in the advanced setting. With a manageable toxicity profile, SG represents a significant advancement in the treatment landscape for this patient population. However, further research is essential to optimize its application and establish long-term benefits.

Elacestrant in ER+, HER2- MBC with ESR1-mutated tumors: Subgroup Analyses from the Phase III EMERALD Trial by Prior Duration of Endocrine Therapy Plus CDK4/6 Inhibitor and in Clinical Subgroups.

PURPOSE: Elacestrant significantly prolonged progression-free survival (PFS) with manageable safety versus standard-of-care (SOC) endocrine therapy (ET) in patients with ER+, HER2- mBC and tumors harboring ESR1 mutation following ET plus a cyclin-dependent kinase 4/6 inhibitor (ET+CDK4/6i). In patients with ESR1-mutated tumors, we evaluated the efficacy and safety of elacestrant versus SOC based on prior ET+CDK4/6i duration, and in clinical subgroups with prior ET+CDK4/6i ≥12 months. METHODS: EMERALD, an open-label phase III trial, randomized patients with ER+, HER2- mBC, 1-2 prior lines of ET, mandatory CDK4/6i, and ≤1 chemotherapy to elacestrant (345 mg daily) or SOC (aromatase inhibitor or fulvestrant). PFS was assessed across subgroups in post-hoc exploratory analyses without adjustment for multiple testing. RESULTS: In patients with ESR1-mutated tumors and prior ET+CDK4/6i ≥12 months, median PFS (mPFS) for elacestrant versus SOC was 8.6 versus 1.9 months (HR, 0.41; 95% CI, 0.26-0.63). In this population, mPFS (in months) for elacestrant versus SOC was 9.1 versus 1.9 (bone metastases), 7.3 versus 1.9 (liver and/or lung metastases), 9.0 versus 1.9 (<3 metastatic sites), 10.8 versus 1.8 (≥3 metastatic sites), 5.5 versus 1.9 (PIK3CA mutation), 8.6 versus 1.9 (TP53 mutation), 9.0 versus 1.9 (HER2-low), 9.0 versus 1.9 (ESR1 D538G-mutated tumors), and 9.0 versus 1.9 (ESR1 Y537S/N-mutated tumors). Subgroup safety was consistent with the overall population. CONCLUSIONS: Duration of prior ET+CDK4/6i ≥12 months in mBC was associated with a clinically meaningful improvement in PFS for elacestrant compared to SOC and was consistent across all subgroups evaluated in patients with ER+, HER2-, ESR1-mutated tumors.

Comprehensive Screening of Genetic Variants in the Coding Region of F8 in Severe Hemophilia A Reveals a Relationship with Disease Severity in a Colombian Cohort.

Hemophilia A is an X-linked disorder characterized by quantitative deficiency of coagulation factor VIII (FVIII) caused by pathogenic variants in the factor 8 (F8) gene. Our study's primary objective was to identify genetic variants within the exonic region of F8 in 50 Colombian male participants with severe hemophilia A (HA). Whole-exome sequencing and bioinformatics analyses were performed, and bivariate analysis was used to evaluate the relationship between identified variants, disease severity, and inhibitor risk formation. Out of the 50 participants, 21 were found to have 17 different pathogenic F8 variants (var). It was found that 70% (var = 12) of them were premature truncation variants (nonsense, frameshift), 17.6% (var = 3) were missense mutations, and 11.7% (var = 2) were splice-site variants. Interestingly, 35% (var = 6) of the identified variants have not been previously reported in the literature. All patients with a history of positive inhibitors (n = 4) were found to have high-impact genetic variants (nonsense and frameshift). When investigating the relationship between variant location (heavy versus light chain) and specific inhibitor risk, 75% (n = 3) of the inhibitor participants were found to have variants located in the F8 light chain (p = 0.075), suggesting that conserved domains are associated with higher inhibitor risk. In summary, we identified genetic variants within the F8 that can possibly influence inhibitor development in Colombian patients with severe HA. Our results provide a basis for future studies and the development of further personalized treatment strategies in this population.

Capivasertib and fulvestrant for patients with hormone receptor-positive, HER2-negative advanced breast cancer (CAPItello-291): patient-reported outcomes from a phase 3, randomised, double-blind, placebo-controlled trial.

BACKGROUND: CAPItello-291 is an ongoing phase 3 trial in which capivasertib-fulvestrant significantly improved progression-free survival versus placebo-fulvestrant in patients with hormone receptor-positive, HER2-negative advanced breast cancer who had relapse or disease progression during or after aromatase inhibitor treatment, in both the overall population and in patients with PIK3CA, AKT1, or PTEN-altered tumours. This study further explored patient-reported health-related quality of life (HRQOL), functioning, symptoms, and symptom tolerability in CAPItello-291. METHODS: This phase 3, randomised, double-blind, placebo-controlled trial, which was conducted across 193 hospitals and cancer centres in 19 countries, enrolled women with any menopausal status or men, aged ≥18 years (≥20 years in Japan), with hormone receptor-positive, HER2-negative locally advanced or metastatic breast cancer who had relapse or disease progression during or after treatment with an aromatase inhibitor, with or without previous cyclin-dependent kinase (CDK) 4 or 6 inhibitor therapy. Patients had an Eastern Cooperative Oncology Group/WHO performance score of 0 or 1 and could have received up to two previous lines of endocrine therapy and up to one previous line of chemotherapy for advanced disease. Patients were randomly assigned (1:1) using block randomisation (stratified according to the presence or absence of liver metastases, previous use of a CDK4/6 inhibitor [yes vs no], and geographical region) to receive oral capivasertib 400 mg (twice daily for 4 days, followed by 3 days off) plus intramuscular fulvestrant 500 mg (every 14 days for the first three injections, then every 28 days) or placebo with matching fulvestrant dosing. The dual primary endpoint of the trial was investigator-assessed progression-free survival assessed both in the overall population and among patients with PIK3CA, AKT1, or PTEN-altered tumours. The EORTC Quality of Life Questionnaire 30-item core module (QLQ-C30) and breast module (QLQ-BR23), Patient-Reported Outcomes version of the Common Terminology Criteria for Adverse Events (PRO-CTCAE), and Patient Global Impression of Treatment Tolerability (PGI-TT) questionnaires were used to assess patient-reported outcomes. Evaluation of EORTC QLQ-C30 and EORTC QLQ-BR23 were secondary endpoints and evaluation of PRO-CTCAE and PGI-TT were pre-defined exploratory endpoints, and these endpoints are the subject of analysis in this Article. Data were collected at baseline and prespecified timepoints. Patient-reported outcomes were analysed in all randomly assigned patients with an evaluable baseline assessment and at least one evaluable post-baseline assessment. Change from baseline was assessed using mixed model with repeated measures for EORTC QLQ-C30 and summarised for QLQ-BR23. Time to deterioration was described using the Kaplan-Meier method. PGI-TT and PRO-CTCAE responses were summarised at each treatment cycle. Patient-reported outcomes were not prospectively powered for statistical comparison. The trial is registered with ClinicalTrials.gov, NCT04305496. FINDINGS: Between June 2, 2020, and Oct 13, 2021, 901 patients were enrolled, of whom 708 patients were randomly assigned to receive capivasertib-fulvestrant (n=355) or placebo-fulvestrant (n=353). The median age of the patients was 59 years (IQR 51-67) in the capivasertib-fulvestrant group and 58 years (IQR 49-66) in the placebo-fulvestrant group. At data cutoff (Aug 15, 2022), the median duration of follow-up for progression-free survival in censored patients was 13·0 months (IQR 9·1-16·7) for capivasertib-fulvestrant and 12·7 months (IQR 2·0-16·4) for placebo-fulvestrant in the overall population. EORTC QLQ-C30 global health status/quality of life (GHS/QOL) scores were maintained from baseline and were similar between treatment groups throughout the study period (difference in mean change from baseline of -2·5 [95% CI -4·5 to -0·6] with capivasertib-fulvestrant vs -5·6 [-7·9 to -3·4] with placebo-fulvestrant; treatment difference 3·1 [95% CI 0·2 to 6·0]). Median time to deterioration in EORTC QLQ-C30 GHS/QOL was 24·9 months (95% CI 13·8 to not reached) in the capivasertib-fulvestrant group and 12·0 months (10·2 to 15·7) in the placebo-fulvestrant group (hazard ratio [HR] 0·70, 95% CI 0·53 to 0·92). Time to deterioration HRs for all EORTC QLQ-C30 and QLQ-BR23 subscale scores showed little difference between the treatment groups, except for diarrhoea, which was worse in the capivasertib-fulvestrant group than in the placebo-fulvestrant group (HR 2·75, 95% CI 2·01-3·81). In PRO-CTCAE symptom assessment, the proportion of patients reporting loose and watery stools "frequently" or "almost constantly" was 29% higher at cycle 1, day 15 in the capivasertib-fulvestrant group than in the placebo-fulvestrant group, decreasing at subsequent cycles. Other PRO-CTCAE-reported symptoms (rash, mouth or throat sores, itchy skin, and numbness or tingling in hands or feet) were absent or mild in most patients in both groups throughout treatment. According to the PGI-TT, most patients in both groups reported "not at all" or "a little bit" of bother from treatment side-effects. INTERPRETATION: Patient-reported outcomes from CAPItello-291 demonstrated that capivasertib-fulvestrant delayed time to deterioration of GHS/QOL and maintained other dimensions of HRQOL (except symptoms of diarrhoea) similarly to fulvestrant. With the clinical efficacy and manageable safety profile, these exploratory results further support the positive benefit-risk profile of capivasertib-fulvestrant in this population. FUNDING: AstraZeneca.

Olaparib plus trastuzumab in HER2-positive advanced breast cancer patients with germline BRCA1/2 mutations: The OPHELIA phase 2 study.

PURPOSE: To evaluate the efficacy and safety of the combination of olaparib plus trastuzumab in patients with HER2-positive advanced breast cancer (ABC) and germinal BRCA mutations (gBRCAm). METHODS: OPHELIA (NCT03931551) was a single-arm, open-label, phase 2 clinical trial. Patients aged ≥18 years diagnosed with HER2-positive ABC with germinal deleterious mutations in BRCA1 or BRCA2 who had received at least one prior systemic regimen for advanced disease were enrolled. Patients received olaparib plus trastuzumab until disease progression, unacceptable toxicity, or consent withdrawal. The primary endpoint was investigator-assessed clinical benefit rate for at least 24 weeks as per RECIST v.1.1. Key secondary endpoints included overall response rate (ORR) and safety profile. RESULTS: A total of 68 pre-treated HER2-positive ABC patients were screened. Due to slow accrual the trial was stopped after enrolling 5 patients instead of the planned sample size of 20. Four patients achieved clinical benefit (80.0 %, 95 % CI; 28.4-99.5, p < 0.001) and the primary endpoint was met. The ORR was 60.0 % (95 % CI; 14.7-94.7), including one complete response. Four (80.0 %) patients experienced at least one treatment-related treatment-emergent adverse event (TEAE). Most TEAEs were grade 1 or 2. There were no treatment-related deaths and no new safety signals were identified. CONCLUSIONS: This study suggests that the combination of olaparib plus trastuzumab may be effective and safe in pre-treated patients with HER2-positive gBRCAm ABC. This ABC patient population should be further studied and not be pre-emptively excluded from clinical trials of targeted therapy for BRCA1/2-driven cancers.

Trastuzumab deruxtecan versus trastuzumab emtansine in Asian patients with HER2-positive metastatic breast cancer.

The global phase 3 DESTINY-Breast03 study (ClinicalTrials.gov; NCT03529110) showed statistically significant and clinically meaningful improvements in progression-free survival (PFS) and overall survival (OS) with trastuzumab deruxtecan (T-DXd) over trastuzumab emtansine (T-DM1) in patients with human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer (mBC) previously treated with trastuzumab and a taxane. Here, we report a subgroup analysis of Asian patients enrolled in DESTINY-Breast03. In total, 309 patients (149 in the T-DXd arm and 160 in the T-DM1 arm) from Asian countries and regions were randomized. At data cutoff (July 25, 2022), the median duration of follow-up in the Asian subpopulation was 29.0 months with T-DXd and 26.0 months with T-DM1. The PFS (determined by blinded independent central review) hazard ratio was 0.30 (95% confidence interval 0.22-0.41) favoring T-DXd over T-DM1 (median PFS 25.1 vs. 5.4 months). Median OS was not reached in the T-DXd arm and was 37.7 months in the T-DM1 arm. The median treatment duration was 15.4 months with T-DXd and 5.5 months with T-DM1. The incidence of grade ≥3 drug-related treatment-emergent adverse events was similar between both treatment arms (49.0% vs. 46.5%) and was consistent with the overall DESTINY-Breast03 population. Adjudicated drug-related interstitial lung disease or pneumonitis occurred in 12.9% of patients treated with T-DXd and 2.5% treated with T-DM1, with a higher incidence in Japanese patients; none of these were grade ≥4 events. These efficacy and safety data reinforce the favorable benefit-risk profile of T-DXd in HER2-positive mBC, including in the Asian subgroup.

Validation of immunohistochemical overexpression of p16 in the histologic diagnosis of cervical intraepithelial neoplasia grade 2.

An accurate cytohistologic diagnosis is important to avoid overtreatment of cervical intraepithelial lesions. The three-tiered Cervical Intraepithelial Neoplasia (CIN) classification, grades 1, 2 and 3, despite poor agreement among pathologists in diagnosing CIN2, is still being used. The College of American Pathologists recommended an alternative two-tiered classification that has not yet been universally accepted. We review the diagnostic results of 286 biopsies performed by three pathologists using haematoxylin and eosin (H&E) and p16 to establish the level of agreement among the readers. Agreement between pathologists in diagnosing CIN2 with H&E was around 45% and improved to 86.7% when interpreting p16 stained biopsies without H&E; agreement with pathologist 3 was lower, around 60%. Discrepant results from one pathologist when assessing p16 highlights the decisive influence of individual criteria. P16 has shown to improve agreement between pathologists with previous good agreement, but did not correct it for the third pathologist. In equivocal cases, protein p16 is a useful conjunctive tool for a histologic diagnosis.

HER2DX Genomic Assay in HER2-Positive Early Breast Cancer Treated with Trastuzumab and Pertuzumab: A Correlative Analysis from the PHERGain Phase II Trial.

PURPOSE: The purpose of this study was to assess the predictive capability of HER2DX assay following (neo)adjuvant trastuzumab-pertuzumab (HP)-based therapy in HER2-positive (HER2+) early breast cancer. EXPERIMENTAL DESIGN: HER2DX was analyzed in baseline pretreatment tumors from the PHERGain trial. Patients with stage I-IIIA HER2+ early breast cancer were randomized to group A [docetaxel, carboplatin, and HP (TCHP)] and group B (HP ± endocrine therapy). PET response was evaluated after two cycles. Group A received TCHP for six cycles regardless of PET response. Group B continued with HP ± endocrine therapy for six cycles (PET responders) or with TCHP for six cycles (PET nonresponders). The primary objective of this retrospective study was to associate the HER2DX pathologic complete response (pCR) score with pCR. The secondary objective was the association of the HER2DX risk score with 3-year invasive disease-free survival (iDFS). RESULTS: HER2DX was performed on 292 (82.0%) tumors. The overall pCR rate was 38.0%, with pCR rates of 56.4% in group A and 33.8% in group B. In multivariable analysis including treatment and clinicopathologic factors, the HER2DX pCR score (continuous variable) significantly correlated with pCR [OR, 1.29; 95% confidence interval (CI), 1.10-1.54; P < 0.001]. HER2DX-defined pCR-high, -med, and -low groups exhibited pCR rates of 50.4%, 35.8%, and 23.2%, respectively (pCR-high vs. pCR-low OR, 3.27; 95% CI, 1.54-7.09; P < 0.001). In patients with residual disease, the HER2DX high-risk group demonstrated numerically worse 3-year iDFS than the low-risk group (89.8% vs. 100%; HR, 2.70; 95% CI, 0.60-12.18; P = 0.197). CONCLUSIONS: HER2DX predicts pCR in the context of neoadjuvant HP-based therapy, regardless of chemotherapy addition, and might identify patients at higher risk of recurrence among patients with residual disease.

6th and 7th International consensus guidelines for the management of advanced breast cancer (ABC guidelines 6 and 7).

This manuscript describes the Advanced Breast Cancer (ABC) international consensus guidelines updated at the last two ABC international consensus conferences (ABC 6 in 2021, virtual, and ABC 7 in 2023, in Lisbon, Portugal), organized by the ABC Global Alliance. It provides the main recommendations on how to best manage patients with advanced breast cancer (inoperable locally advanced or metastatic), of all breast cancer subtypes, as well as palliative and supportive care. These guidelines are based on available evidence or on expert opinion when a higher level of evidence is lacking. Each guideline is accompanied by the level of evidence (LoE), grade of recommendation (GoR) and percentage of consensus reached at the consensus conferences. Updated diagnostic and treatment algorithms are also provided. The guidelines represent the best management options for patients living with ABC globally, assuming accessibility to all available therapies. Their adaptation (i.e. resource-stratified guidelines) is often needed in settings where access to care is limited.

Trastuzumab deruxtecan versus trastuzumab emtansine in HER2-positive metastatic breast cancer: long-term survival analysis of the DESTINY-Breast03 trial.

Trastuzumab deruxtecan (T-DXd) demonstrated significantly improved efficacy over trastuzumab emtansine (T-DM1) in DESTINY-Breast03 (median follow-up, 28 months). We report updated efficacy and safety analyses, including secondary and exploratory efficacy endpoints (median follow-up, 41 months) of DESTINY-Breast03. Patients with advanced HER2-positive metastatic breast cancer previously treated with taxane and trastuzumab were randomized to T-DXd (5.4 mg per kg (261 patients)) or T-DM1 (3.6 mg per kg (263 patients)). The primary endpoint was progression-free survival (PFS) by blinded independent central review and was previously reported. The key secondary endpoint was overall survival (OS). Other secondary endpoints included objective response rate, duration of response and PFS (all by investigator assessment) and safety. At data cutoff, 20 November 2023, median PFS by investigator assessment was 29.0 versus 7.2 months (hazard ratio (HR), 0.30; 95% confidence interval (CI), 0.24-0.38), the 36-month PFS rate was 45.7% versus 12.4% and median OS was 52.6 versus 42.7 months (HR, 0.73; 95% CI, 0.56-0.94) with T-DXd versus T-DM1, respectively. Treatment-emergent adverse events were consistent with the previous analyses. No new instances of grade ≥3 interstitial lung disease or pneumonitis occurred (all grade rate, 16.7% (T-DXd) versus 3.4% (T-DM1)). With longer follow-up, T-DXd continued to demonstrate superior efficacy over T-DM1 with a manageable safety profile. ClinicalTrials.gov registration: NCT03529110 .

Hidden secrets of the cancer genome: unlocking the impact of non-coding mutations in gene regulatory elements.

Discoveries in the field of genomics have revealed that non-coding genomic regions are not merely "junk DNA", but rather comprise critical elements involved in gene expression. These gene regulatory elements (GREs) include enhancers, insulators, silencers, and gene promoters. Notably, new evidence shows how mutations within these regions substantially influence gene expression programs, especially in the context of cancer. Advances in high-throughput sequencing technologies have accelerated the identification of somatic and germline single nucleotide mutations in non-coding genomic regions. This review provides an overview of somatic and germline non-coding single nucleotide alterations affecting transcription factor binding sites in GREs, specifically involved in cancer biology. It also summarizes the technologies available for exploring GREs and the challenges associated with studying and characterizing non-coding single nucleotide mutations. Understanding the role of GRE alterations in cancer is essential for improving diagnostic and prognostic capabilities in the precision medicine era, leading to enhanced patient-centered clinical outcomes.

Randomized Phase III Study of Amcenestrant Plus Palbociclib Versus Letrozole Plus Palbociclib in Estrogen Receptor-Positive, Human Epidermal Growth Factor Receptor 2-Negative Advanced Breast Cancer: Primary Results From AMEERA-5.

PURPOSE: AMEERA-5 investigated amcenestrant (oral selective estrogen receptor [ER] degrader) plus palbociclib versus letrozole plus palbociclib as first-line treatment for ER-positive/human epidermal growth factor receptor 2-negative (ER+/HER2-) advanced/metastatic breast cancer (aBC). MATERIALS AND METHODS: In AMEERA-5 (ClinicalTrials.gov identifier: NCT04478266), a double-blind, double-dummy, international phase III trial, adult pre-/post-menopausal women and men without previous systemic therapy for ER+/HER2- aBC were randomly assigned 1:1 to amcenestrant 200 mg once daily + standard palbociclib dosage (125 mg once daily, 21 days on/7 days off) or letrozole 2.5 mg once daily + standard palbociclib dosage, stratified by de novo metastatic disease, postmenopausal women, and visceral metastasis. The primary end point was progression-free survival (PFS), compared using a stratified log-rank test with one-sided type I error rate of 2.5%. Secondary end points included overall survival (key secondary), pharmacokinetics, and safety. RESULTS: Between October 14, 2020, and December 2, 2021, 1,068 patients were randomly assigned to amcenestrant + palbociclib (N = 534) or letrozole + palbociclib (N = 534). At the interim analysis (median follow-up 8.4 months), the stratified hazard ratio for PFS was 1.209 (95% CI, 0.939 to 1.557; one-sided P value = .9304); therefore, the study was stopped for futility. The 6-month PFS rate was 82.7% (95% CI, 79.0 to 85.8) with amcenestrant + palbociclib versus 86.9% (95% CI, 83.5 to 89.6) with letrozole + palbociclib. In the amcenestrant + palbociclib versus letrozole + palbociclib groups, treatment-emergent adverse events (any grade) occurred in 85.6% versus 85.4% of patients and grade ≥3 events in 46.3% versus 60.8%, respectively. CONCLUSION: The AMEERA-5 study was discontinued on the basis of the recommendation of the data monitoring committee at the interim futility analysis. No new safety signals were identified.