Pan-Asian adapted ESMO Clinical Practice Guidelines for the diagnosis, staging and treatment of patients with metastatic breast cancer

Thymidine kinase 1 concentration and activity in metastatic breast cancer under CDK4/6 inhibitor therapy

We investigated whether TK1 concentration or activity in the blood, drawn at baseline and under therapy, might have value for therapy management in 110 hormone receptor-positive (HR+), HER2-negative (HER2-) metastatic breast cancer (mBC) patients treated with CDK4/6 inhibitors (CDK4/6i) and/or endocrine therapy (ET). TK1 concentration and activity were not significantly correlated with each other in matched samples. In the CDK4/6i cohort at baseline, high TK1 concentration and activity were significantly associated with a decreased PFS and primary resistance. Longitudinal sampling revealed a higher variability of TK1 concentration under therapy compared to TK1 activity that was reduced during therapy. Elevated TK1 activity after six months of CDK4/6i and an increase in TK1 concentration from baseline to six months under CDK4/6i significantly correlated with a decreased PFS. These results indicate a possible value of TK1 concentration and activity before and during CDK4/6i for HR+/HER2- mBC patients to guide treatment that warrants further investigation.

Quality of Life After Locoregional Treatment in Women with De Novo Metastatic Breast Cancer: A Systematic Review and Meta-Analysis

INTRODUCTION

Primary site locoregional treatment (LRT) of metastatic breast cancer has been performed and evaluated with the aim to improve survival, prevent complications, and alleviate local symptoms. As some studies fail to show a survival benefit, the quality of life is important to consider when deciding on LRT. The aim of this study was to evaluate and quantify the impact of LRT on the quality of life of patients with de novo metastatic breast cancer (dnMBC) through a systematic review of the literature and a meta-analysis.

METHODS

Multiple databases were searched on May 2024 with the following keywords: (i) dnMBC; (ii) LRT, including surgery +/- radiotherapy; and (iii) QOL.

RESULTS

Six studies were included in the qualitative synthesis and four in meta-analysis (481 women, n = 251 in the LRT and n = 230 in the control groups). There was a significant QOL decrease in the LRT group at 18 months (standardized mean difference [SMD] = -0.63; 95% confidence interval [CI] -0.98--0.26; p < 0.001, low heterogeneity I2 = 33%) and after 30 months (SMD -0.82; 95%CI -1.58--0.06; p = 0.034, high heterogeneity I2 = 93%), while no statistically significant difference was observed at short term (6 months, p = 0.333).

CONCLUSIONS

This study shows that there is lacking evidence regarding the QOL benefits after LRT in this population, and even a numerical deterioration in global QOL several months after the treatment. Future and ongoing research may provide additional insights into this question on dnMBC and specifics subgroups.

Expression Patterns of Matricellular Proteins in Metastatic Breast Cancer at the Background of Metabolic Syndrome

BACKGROUND

Metastatic breast cancer (mBCa) is one of the main causes of mortality among postmenopausal women with malignant neoplasms. Numerous studies indicate the feasibility of using bone matrix remodeling proteins to predict the BC course.

AIM

To investigate the relationship between osteopontin (OPN) and osteonectin (ON) expression levels in tumor tissue of patients of menopausal age with primary mBCa (pmBCa) and metabolic syndrome (MetS) taking into account the clinicopathological features of the disease.

MATERIALS AND METHODS

The study included 54 menopausal patients with pmBCa, 23 from whom had manifestations of MetS, while 31 patients were without MetS. The expression of matricellular proteins (OPN and ON) was determined immunohistochemically.

RESULTS

In tumor tissue of patients with MetS and pmBCa of category N3, an increase in the level of OPN expression (H-Score of 265.6 ± 7.7, p < 0.05) was recorded along with a decrease in the expression level of ON (H-Score of 123.2 ± 7.7, p < 0.05). The invasive lobular pmBCa in patients with MetS was characterized by a significant decrease in the level of OPN expression ( H-Score of 219.4 ± 8.4) and an increase in ON expression (H-Score of 144.8 ± 7.5). In the patients with MetS, a significant decrease in ON expression (p < 0.05) was recorded in the tumor tissue of luminal A, luminal B, and Her2/neu subtypes ( H-Scores of 140.2 ± 7.8, 119.3 ± 10.2, and 110.0 ± 7.7, respectively). Among the cases of pmBCa with diagnosed metastatic liver disease, ON expression in tumor tissue was lower in patients with MetS (H-Score of 146.2±9.1).

CONCLUSIONS

The obtained data demonstrated the relationship between the expression indicators of matricellular proteins in the pmBCa tissue and the degree of malignancy and indicated the prospects for further studies of their prognostic value in the presence of MetS.

ACE-Breast-02: a randomized phase III trial of ARX788 versus lapatinib plus capecitabine for HER2-positive advanced breast cancer

This phase III trial aimed to compare ARX788, a site-specific, construct-homogeneous antibody-drug conjugate, with lapatinib plus capecitabine in patients with human epidermal growth factor receptor 2 (HER2)-positive advanced breast cancer (ABC) who had progressed on one line of trastuzumab based regimen. Eligible patients were randomized (1:1) to receive ARX788 (1.5 mg/kg, IV, Q3W) or lapatinib plus capecitabine (LC: lapatinib 1250 mg QD; capecitabine 1000 mg/m2 BID, days 1-14, Q3W) and stratified by prior chemotherapy lines (0-1 versus >1) and visceral metastasis (yes versus no). The primary outcome was progression-free survival (PFS) assessed by a blinded independent central review (BICR). A total of 441 patients were randomly assigned to receive either ARX788 (n = 221) or LC (n = 220). The median PFS was 11.3 (95% confidence interval [CI], 8.4-13.8) months with ARX788 compared with 8.2 (95% CI, 6.9-8.7) months with LC, as per BICR (hazard ratio [HR] 0.64, p = 0.0006). Frequencies of treatment-related adverse events (TRAEs) of any grade were 98.6% and 99.1% for ARX788 and LC, respectively. Grade ≥3 TRAEs were 41.4% and 40.0%, respectively, the most common adverse events were blurred vision (12.3%), dry eye (9.1%), keratopathy (5.9%), and interstitial lung disease (ILD, 5.9%) with ARX788; hand-foot syndrome (18.1%) and hypokalemia (5.1%) with LC; all the hematological and gastrointestinal events of grade ≥3 with ARX788 were less than 3%. Six treatment-related deaths occurred, with three cases possibly related to ILD. ARX788 significantly improved PFS compared with LC in patients with HER2-positive ABC with a distinct toxicity profile, supporting it as a potential treatment option.

Advances in antibody-drug conjugates in the treatment of advanced triple-negative breast cancer: a narrative review

Background and Objective

Triple-negative breast cancer (TNBC) is more aggressive when compared with other breast cancer subtypes, and advanced TNBC (aTNBC) has always been a challenge for clinical treatment. In recent years, significant progress has been made in the research of antibody-drug conjugates (ADCs), especially targeting trophoblast cell-surface antigen 2 (TROP2), as an effective regimen to enhance the potential survival benefit and quality of life of relevant patients. The objective of this narrative review is to provide a comprehensive knowledge on latest progress of ADCs in the treatment of aTNBC. Furthermore, the clinical significance and future research directions for ADCs are also discussed.

Methods

As of December 2023, literature spanning the past decade was comprehensively searched and analyzed across PubMed, Wanfang Data, ClinicalTrials.gov, and relevant academic conferences, to identify the latest published literature or ongoing trials on ADCs for aTNBC. The selected literature primarily focused on the drug structural profile, pharmacological mechanism, important trials targeting different antigens, and other exploratory investigations.

Key Content and Findings

The advent of precision therapy has been facilitated by the new generation ADCs, which have demonstrated the capacity to prolong survival in patients with refractory aTNBC, and promote the research on molecular biological characteristics of aTNBC. Meanwhile, several clinical issues on treatment are emerging, including a detailed understanding of the clinical profile differences among specific ADCs, identification of the potential indications for ADCs, and management strategies for the adverse effects related to ADCs. Additionally, it is essential to clarify the clinical significance of the expression level of the target antigen for ADCs, to comprehend resistance mechanisms to ADCs, and to determine the optimal sequence of treatments between different ADCs. Furthermore, there is a need to investigate the potential of combination immunotherapy with ADCs. Up to date, the preliminary investigations on the aforementioned issues have been initiated, and further research will facilitate the enhancement of ADCs clinical utilization.

Conclusions

The use of ADCs has been recommended by various clinical guidelines, and significantly altering the landscape of treatment for aTNBC. Nevertheless, further investigation are required to determine the most effective use of ADCs.

Exploring breast cancer associated-gene panel for next-generation sequencing and identifying new, pathogenic variants in breast cancer from western China

Breast cancer (BC) is the most frequently diagnosed and the leading cause of cancer-related deaths among women worldwide. It is crucial to develop a cost-effective BC genetic panel for detection and diagnosis. In this study, tissue samples from 52 BC patients and peripheral blood samples from 18 healthy volunteers were collected in western China, followed by gDNA extraction. H&E and IHC analysis were employed to detect the expression of invasive BC tissues. We analyzed data using public databases such as COSMIC/ClinVar/HGMD along with our own previously published data and queried commercial BC panels to select high-risk genes. Using Illumina DesignStudio, gene panel primers consisting of 13 genes were designed with 696 primer pairs. The specificity of all primers was validated through common PCR assays. Once the gene panel was completed, multiple polymerase chain reactions (MPCR) were performed using the designed panel primers. The resulting MPCR products were purified to enrich them as library templates. Subsequently, after passing quality tests for library integrity assessment, Next-generation sequencing (NGS) was conducted. Through bioinformatics analysis of the NGS data, 4,571 variants were identified in the annotation files from 52 samples, classified into different types. Among these variants, 358 (approximately 7.8%) were newly discovered and distributed across 11 genes in 52 patients without in the ExAC database. The KMT2C gene exhibited the highest frequency of variants, presenting in 83.0% of 52 patient samples. Variants in BRCA2 (71%), BRCA1 (48%), PALB2 (40%), PIK3CA (23%), and RNF40 (21%) genes were found in over 20% of patients. Additionally, variants were observed in the AKT1 (12%), ERBB2 (10%), ESR1 (8%), TWIST1 (8%), and PIK3R1 (4%) genes. Further analysis using PolyPhen-2, SIFT, CADD, and Mutation Taster tools analysis showed that out of these new variants, 49 (49/358) had potential pathogenic effects on protein functions and structure across 52 patients. Consequently, a high-risk gene panel has been preliminarily established for early detection/diagnosis that will contribute to earlier prevention and treatment strategies for individuals with BC, particularly those residing in developing or underdeveloped countries. The identification of novel pathogenic variants within our cohort not only expands knowledge regarding genetic diagnosis applications for BC patients but also facilitates genetic counseling services for affected individuals and their families.

Retrospective comparative survival analysis of ablation plus systemic therapy versus systemic therapy alone for breast cancer liver metastases, stratified by extrahepatic metastases status

BACKGROUND

Current decision-making for the treatment of breast cancer liver metastases (BCLM) using ablation lacks strong evidence, especially for patients combined with extrahepatic metastases.

PURPOSE

To assess whether ablation plus systemic therapy (AS) improves survival outcomes in patients with BCLM compared to systemic therapy alone.

MATERIALS AND METHODS

This retrospective study analyzed patients with BCLM who received either AS or systemic therapy alone. Propensity score matching (PSM) and survival analysis were performed, taking into account factors like the characteristics of primary breast cancer, liver metastases and systemic therapies received.

RESULTS

The study included 1021 female patients, with a median follow-up of 39.6 months. Of these patients, 132 underwent AS and 836 received systemic therapy alone. After PSM, among patients with BCLM (≤3 tumors, each ≤3 cm), the median overall survival (OS) for those treated with AS or systemic therapy alone was 65.5 and 40.4 months, respectively (HR = 0.48, p = .003); in the subset of patients with extrahepatic metastases, the median OS for those treated with AS and systemic therapy alone was 46.4 and 40.8 months, respectively (HR = 0.58, p = .047). Among patients with >3 cm or >3 lesions, the median OS for those treated with AS or systemic therapy alone was 45.2 and 29 months, respectively (HR = 0.67, p = .084).

CONCLUSIONS

Among patients with BCLM (≤3 tumors, each ≤3 cm), AS provide longer survival compared to systemic therapy alone, even with extrahepatic metastases. For patients with larger or more numerous metastases (>3 cm or >3 lesions), AS may provide survival benefit, but further validation is needed.

Long-Term Survival of Metachronous Isolated Adrenal Metastasis in Luminal Breast Cancer: A Case Report and Literature Review

Metachronous metastasis occurs many years later in cases of hormone-positive, human epidermal growth factor receptor 2 (HER2)-negative breast cancer, with the most common sites being the lymph nodes, bones, liver, lungs, and brain. The late recurrence of estrogen receptor (ER)-positive breast cancer is attributed to prolonged adjuvant therapy and the high expression of dormancy-associated genes, allowing cancer cells to survive for decades without proliferating. It is a form of chronic breast cancer that remains asymptomatic, with no clinical signs of progression or recurrence. Estrogen receptor-negative breast cancers, on the other hand, have no long-term tumor dormancy due to their fast growth and low expression of dormancy-related genes. Adrenal gland metastasis, particularly as an oligometastatic presentation, is exceedingly rare, and optimal treatment strategies remain elusive. In this report, we present a case demonstrating long-term survival after treatment of adrenal gland metastasis, accompanied by a comprehensive literature review. At the age of 48, our patient was diagnosed with invasive ductal carcinoma of the left breast. Treatment included breast-conserving surgery, radiotherapy, and adjuvant hormone therapy. Ten years later, she developed a solitary left adrenal metastasis. Treatment included laparoscopic adrenalectomy and a change in hormonal therapy. Our patient is currently still asymptomatic with no evidence of disease. Her overall survival of over 20 years is exceptional. Resection of the adrenal metastasis combined with systemic hormonal therapy represents the recommended approach for this metachronous metastasis. In the contemporary context, antihormonal therapy in combination with CDK4/6 inhibitors should be considered. The present case underscores the necessity of establishing a lifelong (inter)national cancer registry to document rare recurrences systematically. Such a registry would provide insights into the prevalence of uncommon scenarios and offer invaluable data on proposed treatments, facilitating the development of uniform treatment strategies.

Optimizing Premenopausal Hormone Receptor-Positive Human Epidermal Growth Factor Receptor 2-Negative Early Breast Cancer Management in India: Insights From Expert Consensus

This research aims to optimize adjuvant ovarian function suppression (OFS) for premenopausal Indian women with hormone receptor-positive (HR+) /human epidermal growth factor receptor 2-negative (HER2-) early breast cancer (eBC). To address specific challenges identified in clinical practice, a comprehensive questionnaire consisting of 21 statements was developed. These statements were reviewed and validated by a scientific committee, ensuring their accuracy and relevance to the study's objectives. A panel of 46 Indian experts and one global expert in the field of eBC were asked to rate their level of agreement/disagreement with each statement. Consensus was defined as achieving ≥80% agreement among participants. Following two rounds of the modified Delphi technique, a consensus was achieved on 19 out of 21 statements addressing critical aspects of premenopausal HR+ HER2- eBC management. The expert panel strongly recommended comprehensive risk stratification for premenopausal patients with HR+ HER2- eBC, highlighting age ≤40 as a high-risk factor and advising composite assessments for patients ≥40 years. For high-risk patients, OFS coupled with an aromatase inhibitor emerged as the recommended therapeutic strategy. The panel recommended a potential duration of up to five years for OFS, provided tolerability is maintained. For patients under 40, simultaneous OFS and chemotherapy is advised when needed. For those over 40, sequential initiation is acceptable. Triptorelin is preferred among luteinizing hormone-releasing hormone analogs, though all options have similar efficacies. The outcomes of this consensus offer valuable clinical guidance, enabling individualized and evidence-based approaches for OFS in Indian patients with HR+ HER2- eBC.

Sacituzumab govitecan in HR+HER2- metastatic breast cancer: the randomized phase 3 EVER-132-002 trial

Sacituzumab govitecan (SG) significantly improved progression-free survival (PFS) and overall survival (OS) versus chemotherapy in hormone receptor-positive human epidermal growth factor receptor 2-negative (HR+HER2-) metastatic breast cancer (mBC) in the global TROPiCS-02 study. TROPiCS-02 enrolled few Asian patients. Here we report results of SG in Asian patients with HR+HER2- mBC from the EVER-132-002 study. Patients were randomized to SG (n = 166) or chemotherapy (n = 165). The primary endpoint was met: PFS was improved with SG versus chemotherapy (hazard ratio of 0.67, 95% confidence interval 0.52-0.87; P = 0.0028; median 4.3 versus 4.2 months). OS also improved with SG versus chemotherapy (hazard ratio of 0.64, 95% confidence interval 0.47-0.88; P = 0.0061; median 21.0 versus 15.3 months). The most common grade ≥3 treatment-emergent adverse events were neutropenia, leukopenia and anemia. SG demonstrated significant and clinically meaningful improvement in PFS and OS versus chemotherapy, with a manageable safety profile consistent with prior studies. SG represents a promising treatment option for Asian patients with HR+HER2- mBC (ClinicalTrials.gov identifier no. NCT04639986 ).

Neutrophil-to-lymphocyte ratio at the end of treatment with CDK4/6 inhibitors is an independent prognostic factor for ER-positive HER2-negative advanced breast cancer

PURPOSE

The aim of this study was to elucidate the clinical significance of peripheral blood biomarkers, including absolute lymphocyte count (ALC) and neutrophil-to-lymphocyte ratio (NLR), at the end of treatment (EOT) with CDK4/6 inhibitors abemaciclib and palbociclib in patients with estrogen receptor-positive human epidermal growth factor receptor 2-negative advanced breast cancer.

METHODS

We included 67 patients treated with fulvestrant plus abemaciclib or palbociclib. Overall survival (OS) since the EOT with CDK/4/6 inhibitors was compared in relation to the levels of ALC and NLR. The cut-off values of ALC and NLR were set at 1000/μL and 3, respectively.

RESULTS

Patients with a high ALC at EOT showed significantly longer OS than those with a low ALC (p = 0.0358). Moreover, patients with a low NLR at EOT showed significantly longer OS than those with a high NLR at EOT (p = 0.0044). Looking at the changes of ALC and NLR between baseline and the EOT, patients with a high ALC both at baseline and at the EOT showed significantly longer OS than others (p = 0.0201). Similarly, patients with a low NLR both at baseline and at the EOT showed significantly longer OS after EOT than others (p = 0.0136). Multivariable analysis revealed that the NLR at EOT (low vs. high) and changes in NLR (low at baseline to low at EOT vs. others) were significant and independent prognostic factors for OS after EOT (p = 0.0337, p = 0.0039, respectively).

CONCLUSION

NLR at EOT with CDK4/6 inhibitors is a significant and independent prognostic marker for patients with ER-positive HER2-negative advanced breast cancer.

Traditional Chinese Medicine Herbs for Breast Cancer Prevention and Survival: A Narrative Review of Epidemiological Studies from Taiwan

PURPOSE OF REVIEW

This review aims to describe the association of integrating traditional Chinese medicine (TCM) herbs into conventional medicine (CM) in preventing breast cancer and improving survival rates among breast cancer patients of Taiwan.

RECENT FINDINGS

Of 7 relevant studies, spanning 2014-2023, 4 investigated breast cancer risk in women with menopausal symptoms and other comorbidities. All 4 reported that TCM herbal use was associated with lower risks of developing breast cancer. Three studies investigated survival in newly-diagnosed breast cancer patients receiving CM. All reported that adjunctive TCM users had lower mortality rates than CM-only patients. However, the heterogeneity of study designs, populations, and interventions may limit the generalizability and robustness of the findings. TCM herbs may promote breast cancer prevention and survival when used alongside CM. More rigorous observational research and clinical trials in specific patient populations are needed to guide clinical decision-making.

Preliminary results from ASCENT-J02: a phase 1/2 study of sacituzumab govitecan in Japanese patients with advanced solid tumors

BACKGROUND

Sacituzumab govitecan (SG) is a Trop-2-directed antibody-drug conjugate approved outside Japan for second-line and later metastatic triple-negative breast cancer (mTNBC), based on the ASCENT study (NCT02574455). We report SG safety and efficacy in an open-label, phase 1/2 bridging study in Japanese patients with advanced solid tumors (ASCENT-J02; NCT05101096; jRCT2031210346).

METHODS

Phase 1 was a standard 3 + 3 design. Patients received intravenous SG 6 mg/kg, escalating to 10 mg/kg, on Days 1 and 8 per 21-day cycle; primary endpoints were safety, incidence of dose-limiting toxicity/toxicities (DLTs), and determination of the recommended phase 2 dose (RP2D). In the multicohort phase 2 study, patients in the mTNBC cohort with previously treated disease received SG at the RP2D; primary endpoint was independent review committee (IRC)-assessed objective response rate (ORR; RECIST v1.1). Safety was a secondary endpoint.

RESULTS

In phase 1 (N = 15), one DLT (grade 3 elevated transaminases) occurred with SG 10 mg/kg; RP2D was SG 10 mg/kg regardless of UGT1A1 status. In phase 2, 36 patients with mTNBC received SG 10 mg/kg. At median follow-up of 6.1 months, IRC-assessed ORR was 25.0% (95% CI 12.1-42.2; P = 0.0077). Median progression-free survival was 5.6 months (95% CI 3.9-not reached [NR]); median overall survival was NR. No treatment-emergent adverse events led to discontinuation or death.

CONCLUSIONS

SG RP2D was established as 10 mg/kg in Japanese patients. SG showed efficacy in Japanese patients with previously treated mTNBC, a manageable safety profile, and no new safety signals, consistent with the previous ASCENT study.

Her2 positive metastatic breast cancer treated with low dose lapatinib in a resource-constrained setting in South India: a retrospective audit

Despite the development of newer anti-Her2 agents, access to these medicines is still restricted with lapatinib being widely used as a second-line agent in Her2-positive metastatic breast cancer. However, lapatinib at approved doses of 1,250 to 1,500 mg/day contributes to a high pill burden and financial toxicity. In a population that has an average national per capita income of only USD 2238.1, lapatinib alone contributes to a financial burden of USD 6153.56 per year (approximately USD 500 per month). A concept of 'value meal' has been suggested - the higher bioavailability of lapatinib with the meal being exploited to reduce its administered dose. This concept was utilised in a resource-constrained tertiary care center in South India and we report the outcomes. In our institution, consecutive patients with Her2 positive metastatic breast cancer from 1 January 2014 to 31 December 2020 who could not afford trastuzumab, lapatinib or any other anti-Her2 agent were offered low-dose lapatinib, 500 mg daily with meal. We conducted a retrospective cohort study of the safety and efficacy of this regimen. Among the 47 patients who received low-dose lapatinib, the majority had de novo metastatic disease (57.4%) and multiple visceral metastases (48.9%). The median number of lines of treatment before lapatinib was one. The disease control rate with lapatinib was 61.7%. The median progression-free survival was 7 months (95% CI: 5.6-8.4 months). The median duration of response was 4.5 months, ranging from 1.3 to 45.8 months. Only eleven patients (23.4%) experienced toxicity, mainly dermatological, with grade 3 in only one (2.1%) and no grade 4 toxicities. Low-dose lapatinib is a regimen that offers an acceptable disease control rate. This strategy requires further exploration, particularly for the benefit of resource-limited areas.

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.

Palbociclib in HR-Positive, HER2-Negative Advanced/Metastatic Breast Cancer: A Systematic Scoping Review of Real-World Evidence from Countries Outside of Western Regions that Are Underrepresented in Clinical Trials

INTRODUCTION

Limited awareness exists regarding real-world data (RWD) for palbociclib in patients with hormone receptor-positive, human epidermal growth factor receptor 2-negative advanced/metastatic breast cancer in populations from certain countries outside of Western regions.

METHODS

A systematic scoping review was conducted using PubMed and Embase to evaluate RWD for palbociclib from countries outside of Western regions that are underrepresented in clinical trials. Search criteria were aligned with our research question for relevant English-language publications, without restrictions on publication date, followed by Phase 1 (title and abstract) and Phase 2 (full-text) screening of retrieved citations as per Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Data analyses of eligible studies were done separately for abstracts and full-text publications to enhance the precision and reliability of the results.

RESULTS

Database search yielded 1485 non-duplicate records, 46 qualified for inclusion, of which 47.8% were published as full text. The analysis of outcomes, based exclusively on full-text publications that collectively included 2048 patients treated with palbociclib, revealed the median progression-free survival (PFS) of 20.2-36.7 months, overall survival (OS) of 39.9 months (reported in one publication) and objective response rate (ORR) of 45.3-80.0% with first-line treatment. In ≥ second line, the median PFS, OS and ORR ranged from 7.0 to 24.2 months, 11 to 19.6 months, and 13.9% to 47.9%, respectively. The safety profile of palbociclib was similar to that reported in pivotal clinical studies, and no new safety concerns were identified.

CONCLUSIONS

A comprehensive volume of evidence demonstrates that palbociclib's effectiveness and safety profile in real-world settings align with those observed in clinical trials, offering valuable insights for clinical decision-making in countries outside of Western regions underrepresented in clinical trials.

Trastuzumab deruxtecan versus treatment of physician's choice in previously treated Asian patients with HER2-low unresectable/metastatic breast cancer: subgroup analysis of the DESTINY-Breast04 study

BACKGROUND

In the global phase 3 DESTINY-Breast04 study (NCT03734029), the anti-human epidermal growth factor 2 (HER2) antibody-drug conjugate trastuzumab deruxtecan (T-DXd) demonstrated a statistically significant improvement in progression-free survival (PFS) and overall survival (OS), with manageable safety compared with treatment of physician's choice (TPC) in patients with HER2-low metastatic breast cancer (mBC) who had received 1-2 prior lines of chemotherapy.

METHODS

This subgroup analysis examined the efficacy and safety of T-DXd versus TPC in 213 patients from Asian countries and regions who were enrolled in the DESTINY-Breast04 trial and randomized to T-DXd (n = 147) or TPC (n = 66).

RESULTS

Median PFS with T-DXd and TPC was 10.9 and 5.3 months, respectively, in Asian patients with hormone receptor-positive mBC, and 10.9 and 4.6 months, respectively, in the overall Asian population. In both populations, median OS was not reached with T-DXd and was 19.9 months with TPC. The objective response rate was higher with T-DXd versus TPC in all Asian patients. Median treatment duration was 8.4 months with T-DXd and 3.5 months with TPC. The most common grade ≥ 3 drug-related treatment-emergent adverse events in Asian patients treated with T-DXd were neutropenia (16.3%), anemia (12.9%), and leukopenia (11.6%); the incidences of neutropenia and leukopenia were higher with TPC versus T-DXd. Adjudicated drug-related interstitial lung disease or pneumonitis with T-DXd was 14.3%; the majority of events were grade 1-2.

CONCLUSIONS

T-DXd demonstrated clinically meaningful survival benefits versus TPC in Asian HER2-low mBC patients, regardless of hormone receptor status, with no new safety signals.

CLINICAL TRIAL REGISTRATION NUMBER

ClinicalTrials.gov, NCT03734029.

Screening and Testing for Homologous Recombination Repair Deficiency (HRD) in Breast Cancer: an Overview of the Current Global Landscape

PURPOSE OF REVIEW

Homologous recombination repair deficiency (HRD) increases breast cancer susceptibility and influences both prophylactic and active management of breast cancer. This review evaluates HRD testing and the therapeutic implications of HRD in a global context.

RECENT FINDINGS

Ongoing research efforts have highlighted the importance of HRD beyond BRCA1/2 as a potential therapeutic target in breast cancer. However, despite the improved affordability of next-generation sequencing (NGS) and the discovery of PARP inhibitors, economic and geographical barriers in access to HRD testing and breast cancer screening do not allow all patients to benefit from the personalized treatment approach they provide. Advancements in HRD testing modalities and targeted therapeutics enable tailored breast cancer management. However, inequalities in access to testing and optimized treatments are contributing to widening health disparities globally.

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 .

Drug exposure and risk factors of maculopathy in tamoxifen users

Tamoxifen, a pivotal therapy for hormone receptor-positive breast cancer, is known for its efficacy in reducing breast cancer recurrence and mortality. However, concerns about potential ocular complications, particularly maculopathy, have emerged. This study aims to investigate the risk and associated factors of diverse macular conditions in tamoxifen users, considering drug exposure, demographics, and systemic diseases. A nationwide cohort of tamoxifen users, comprised of 14,267 tamoxifen users, was analyzed using the health insurance review and assessment database in South Korea. Demographic and clinical characteristics were examined, and the cumulative incidence of macular diseases was stratified by age and cumulative tamoxifen dosage. We conducted logistic regression analysis to identify potential risk factors among clinical variables such as age, sex, indications for tamoxifen use, and systemic diseases associated with various macular conditions. Additionally, Cox proportional hazard models were used to determine the baseline clinical characteristics predictive of these macular conditions, with subsequent calculation of hazard ratios. Cumulative incidences of overall macular diseases, other maculopathy excluding common macular diseases, and macular edema were 26.4, 11.4, and 6.5%, respectively. The incidence of various macular conditions increased with age and the cumulative tamoxifen dose. Age, cumulative dose group, and liver diseases demonstrated significant associations with overall macular diseases and maculopathy excluding common macular diseases in multivariate logistic regression analyses (all P < 0.05). Furthermore, age emerged as significant predictive factors of maculopathy in Cox proportional hazard models. Tamoxifen-induced maculopathy poses a concern for prescribing physicians and ophthalmologists, and this study provides valuable insights into its risk and risk factors. This study may contribute to evidence-based guidelines for tamoxifen maculopathy screening, emphasizing the importance of considering age, cumulative dose, and liver diseases for recommendation on screening timing and frequency.

Genomic Landscape of Circulating Tumor DNA in Patients With Hormone Receptor-Positive/Human Epidermal Growth Factor Receptor-2-Negative Metastatic Breast Cancer Treated With Abemaciclib: Data From the SCRUM-Japan Cancer Genome Screening Project

PURPOSE

To understand the mutational landscape of circulating tumor DNA (ctDNA) and tumor tissue of patients with hormone receptor-positive (HR+), human epidermal growth factor receptor-2-negative (HER2-) metastatic breast cancer (MBC) treated with abemaciclib + endocrine therapy (ET).

METHODS

Blood samples for ctDNA and/or tissue samples were collected from abemaciclib-treated patients with HR+/HER2- MBC enrolled in the SCRUM-Japan MONSTAR-SCREEN project. Blood samples were collected before abemaciclib initiation (baseline) and at disease progression/abemaciclib discontinuation (post abemaciclib treatment). Clinical and genomic characteristics including neoplastic burden (measured by shedding rate and maximum variant allele frequency [VAF]) were assessed at baseline. Genomic alterations in ctDNA were compared in paired baseline and post abemaciclib treatment samples.

RESULTS

All patients (N = 97) were female (median age, 57 years [IQR, 50-67]). In baseline ctDNA (n = 77), PIK3CA (37%), TP53 (28%), ESR1 (16%), and GATA3 (11%) were the most frequently mutated genes. Baseline tissue samples (n = 79) showed similar alteration frequencies. Among patients with baseline ctDNA data, 30% had received previous ET. ESR1 alteration frequency (35% v 8%; P < .01), median shedding rate (3 v 2), and maximum somatic VAF (4 v 0.8; both P < .05) were significantly higher in ctDNA from patients with previous ET than those without previous ET. In paired ctDNA samples (n = 33), PIK3CA and ESR1 alteration frequencies were higher after abemaciclib treatment than at baseline, though not statistically significant. Among the post-treatment alterations, those newly acquired were detected most frequently in FGF3/4/19 (18%); PIK3CA, TP53, CCND1, and RB1 (all 15%); and ESR1 (12%).

CONCLUSION

We summarized the ctDNA and cancer tissue mutational landscape, including overall neoplastic burden and PIK3CA and ESR1 hotspot mutations in abemaciclib-treated patients with HR+/HER2- MBC. The data provide insights that could help optimize treatment strategies in this population.

Advanced Breast Cancer Care: The Current Situation and Global Disparities

OBJECTIVES

Advanced breast cancer (ABC) is an incurable disease. The number of people living with ABC has increased globally. Disparities in ABC care exist at both individual and system levels. ABC cases in most low- and middle-income countries (LMICs) are underreported due to a lack of national cancer registries. Harmonized guidelines for resource stratification and capacity building in LMICs are under way.

DATA SOURCES

MEDLINE, Cochrane, and Google Scholar databases were used.

CONCLUSION

To improve ABC outcomes and resolve disparities, more robust health systems or pathways need to be developed across the cancer continuum in addition to social education.

IMPLICATIONS FOR NURSING PRACTICE

So far, the ABC specialist nurse role has been variable globally, and to conquer such variability, an international online nurse education and training program is in practice.

Ratios of monocytes and neutrophils to lymphocytes in the blood predict benefit of CDK4/6 inhibitor treatment in metastatic breast cancer

Biomarkers to identify metastatic breast cancer (mBC) patients resistant to CDK4/6 inhibition (CDK4/6i) are currently missing. We evaluated the usefulness of the monocyte-to-lymphocyte ratio (MLR), the neutrophil-to-lymphocyte ratio (NLR) and the platelet-to-lymphocyte ratio (PLR) as predictive markers for de novo resistance to CDK4/6i. Various blood cell counts and MLR, NLR, PLR were recorded before treatment initiation (baseline) and four weeks later from 97 mBC patients receiving endocrine therapy (ET) alone or in combination with CDK4/6i. Binary blood cell count/ratios (mean = cut-off) were related to outcome using Cox regression. High MLR (p = 0.001) and high NLR (p = 0.01) at baseline significantly correlated with a shorter progression-free survival (PFS) in the CDK4/6i cohort, independent of any other clinical parameter as determined by multivariate Cox regression. Both, high MLR (p = 0.008) and high NLR (p = 0.043) as well as a decrease in PLR after four weeks of CDK4/6i first line treatment (p = 0.01) indicated a shorter overall survival. Moreover, decreasing PLR (p = 0.043) and increasing mean corpuscular volume (MCV; p = 0.011) within the first cycle of CDK4/6i correlated with a shorter PFS and decreasing MLR (p = 0.039) within the first cycle of first-line CDK4/6i was also correlated with shorter PFS. In summary, easily assessable blood cell parameter were shown to have predictive, monitoring and prognostic value and thus, could, in future, be used for individualized CDK4/6i therapy management. Most importantly, the imbalance of NLR and MLR at baseline might serve as predictive marker for de novo resistance to CDK4/6i in mBC patients.

Real-world treatment patterns and outcomes of pyrotinib-based therapy in patients with HER2-positive advanced breast cancer (PRETTY): A nationwide, prospective, observational study

Pyrotinib, an irreversible pan-ErbB inhibitor, has been approved for treating HER2-positive advanced breast cancer in China. We conducted a nationwide, prospective observational study to examine the real-world data of pyrotinib-based therapy in this population. Patients from 61 sites across China were included. Pyrotinib-based regimens were prescribed at local physician's discretion. Demographics, treatment patterns, prognosis and safety were evaluated. The primary outcome was real-world progression-free survival (rwPFS). Of 1129 patients, pyrotinib-based therapy was prescribed as first-, second- and third- or later-line treatment in 437 (38.7%), 476 (42.2%) and 216 (19.1%) patients, respectively. Median rwPFS (mrwPFS) was 14.3 (95% CI, 13.3-15.2) months in the total population, with the longest mrwPFS of 17.8 (95% CI, 15.2-24.9) months in the first-line setting, followed by 14.4 (95% CI, 12.9-15.3) months in the second-line setting. Patients with third- or later-line treatment also achieved a mrwPFS of 9.3 (95% CI, 8.4-11.8) months. Patients with trastuzumab- or trastuzumab-pertuzumab-treated disease achieved a mrwPFS of 14.3 and 13.6 months, respectively. Dual HER2 blockade with pyrotinib plus trastuzumab showed a mrwPFS of 16.2 months in the total population, with data not mature in the first-line setting. For patients with baseline brain metastases, the mrwPFS was 11.7 months. The most common adverse event was diarrhea (any grade, 73.5%; grade ≥ 3, 15.3%). In real world, pyrotinib-based therapy shows promising effectiveness in the first-, as well as second- and later-line treatment, with acceptable tolerability. Further investigations regarding front-line use or novel combinations of pyrotinib might facilitate to maximize its anti-tumor potential.