Age- and ethnic-driven molecular and clinical disparity of East Asian breast cancers.

BACKGROUND: Breast cancer (BC) is a complex disease with profound genomic aberrations. However, the underlying molecular disparity influenced by age and ethnicity remains elusive. METHODS: In this study, we aimed to investigate the molecular properties of 843 primary and metastatic BC patients enrolled in the K-MASTER program. By categorizing patients into two distinct age subgroups, we explored their unique molecular properties. Additionally, we leveraged large-scale genomic data from the TCGA and MSK-IMPACT studies to examine the ethnic-driven molecular and clinical disparities. RESULTS: We observed a high prevalence of PI3KCA mutations in K-MASTER HER2 + tumors, particularly in older patients. Moreover, we identified increased mutation rates in DNA damage response molecules, including ARID1A, MSH6, and MLH1. The K-MASTER patients were mainly comprised of triple-negative breast cancer (TNBC) and HER2-positive tumors, while the TCGA and MSK-IMPACT cohorts exhibited a predominance of hormone receptor-positive (HR +) subtype tumors. Importantly, GATA3 mutations were less frequently observed in East Asian patients, which correlated with poor clinical outcomes. In addition to characterizing the molecular disparities, we developed a gradient-boosting multivariable model to identify a new molecular signature that could predict the therapeutic response to platinum-based chemotherapy. CONCLUSIONS: Our findings collectively provide unprecedented insights into the significance of age and ethnicity on the molecular and clinical characteristics of BC patients.

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).

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.

SGLT2 inhibition improves PI3Kα inhibitor-induced hyperglycemia: findings from preclinical animal models and from patients in the BYLieve and SOLAR-1 trials.

PURPOSE: Alpelisib plus fulvestrant demonstrated a significant progression-free survival benefit versus fulvestrant in patients with PIK3CA-mutated HR+ /HER2- advanced breast cancer (ABC) (SOLAR-1). Hyperglycemia, an on-target adverse effect of PI3Kα inhibition, can lead to dose modifications, potentially impacting alpelisib efficacy. We report data from preclinical models and two clinical trials (SOLAR-1 and BYLieve) on Sodium glucose cotransporter 2 inhibitor (SGLT2i) use to improve PI3Kα inhibitor-associated hyperglycemia. METHODS: Healthy Brown Norway (BN), mild diabetic Zucker diabetic fatty (ZDF), and Rat1-myr-p110α/HBRX3077 tumor-bearing nude rats treated with alpelisib were analyzed for glucose and insulin control with metformin and dapagliflozin (SGLT2i) and alpelisib efficacy. Hyperglycemia adverse events (AEs) were compared between patients receiving SGLT2i with alpelisib (n = 19) and a propensity score-matched cohort not receiving SGLT2i (n = 74) in both trials. RESULTS: Dapagliflozin and metformin in BN and ZDF rats treated with alpelisib normalized blood glucose and reduced insulin levels. No signs of ketosis or drug-drug interaction were observed when metformin and dapagliflozin was administered with alpelisib. Alpelisib antitumor efficacy was maintained when used with dapagliflozin in tumor-bearing rats. Compared with a matched set of patients without SGLT2i, patients receiving SGLT2i had 4.9 and 6.4 times lower rates of grade ≥ 3 hyperglycemia AEs and hyperglycemia AEs resulting in alpelisib dose adjustments, interruptions, or withdrawals, respectively, and a relative reduction in risk of experiencing these AEs (70.6% and 35.7%). CONCLUSION: These data suggest adding an SGLT2i can effectively manage hyperglycemia, resulting in fewer alpelisib dose modifications and discontinuations in patients with PIK3CA-mutated HR+ /HER2- ABC (SOLAR-1: NCT02437318; BYLieve: NCT03056755).

Long-term hepatobiliary disorder associated with trastuzumab emtansine pharmacovigilance study using the FDA Adverse Event Reporting System database.

Trastuzumab emtansine (T-DM1) is widely utilized as a second-line and subsequent treatment for metastatic HER2+ breast cancer and has shown promise in early breast cancer treatment, particularly in adjuvant settings for residual disease after neoadjuvant chemotherapy. However, concerns have arisen regarding long-term hepatic adverse drug reactions (ADRs) not identified in clinical trials. We investigated potential safety signals of T-DM1 in hepatobiliary disorders and the time-to-onset of ADRs using the FDA Adverse Event Reporting System (FAERS) database. Suspected ADRs were extracted and divided into two groups: T-DM1 (N = 3387) and other drugs (N = 11,833,701). Potential signal for T-DM1 in hepatobiliary disorder were identified (reporting odds ratio [ROR] = 5.66, 95% confidence interval [CI] = 5.11-6.27; information component [IC] = 2.35, 95% Credibility Interval [Crl] = 2.18-2.51). A breast cancer indicated subgroup analysis (2519 T-DM1; 172,329 other drugs) also identified a potential safety signal (ROR = 3.28, 95% CI = 2.92-3.68; IC = 1.53, 95%CrI = 1.35-1.71). The median time-to-onset for T-DM1-associated hepatobiliary disorders was 41 days. For prolonged and chronic hepatobiliary disorders, median times were 322.5 and 301.5 days, respectively. These findings highlight the need for further research to inform clinical decisions on optimal T-DM1 treatment duration, balancing benefits with potential adverse reactions.

Real-time assessment of relative mitochondrial ATP synthesis response against inhibiting and stimulating substrates (MitoRAISE).

BACKGROUND: Mitochondria are known to synthesize adenosine triphosphate (ATP) through oxidative phosphorylation. Understanding and accurately measuring mitochondrial ATP synthesis rate can provide insights into the functional status of mitochondria and how it contributes to overall cellular energy homeostasis. Traditional methods only estimate mitochondrial function by measuring ATP levels at a single point in time or through oxygen consumption rates. This study introduced the relative mitochondrial ATP synthesis response against inhibiting and stimulating substrates (MitoRAISE), designed to detect real-time changes in ATP levels as the cells respond to substrates. METHODS: The sensitivity and specificity of the MitoRAISE assay were verified under various conditions, including the isolation of mitochondria, variations in cell numbers, cells exhibiting mitochondrial damage, and heterogeneous mixtures. Using peripheral blood mononuclear cells (PBMCs), we analyzed MitoRAISE data from 19 patients with breast cancer and 23 healthy women. RESULTS: The parameters observed in the MitoRAISE data increased depending on the quantity of isolated mitochondria and cell count, whereas it remained unmeasured in mitochondrial-damaged cell lines. Basal ATP, rotenone response, malonate response, and mitochondrial DNA copy numbers were lower in PBMCs from patients with breast cancer than in those from healthy women. CONCLUSIONS: The MitoRAISE assay has demonstrated its sensitivity and specificity by measuring relative ATP synthesis rates under various conditions. We propose MitoRAISE assay as a potential tool for monitoring changes in the mitochondrial metabolic status associated with various diseases.

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.

Genomic and transcriptomic profiles associated with response to eribulin and nivolumab combination in HER-2-negative metastatic breast cancer.

BACKGROUND: Biomarkers for predicting response to the immunotherapy and chemotherapy combination in breast cancer patients are not established. In this study, we report exploratory genomic and transcriptomic analyses of pretreatment tumor tissues from patients enrolled in phase II clinical trial of a combination of eribulin and nivolumab for HER-2-negative metastatic breast cancer (MBC) (KORNELIA trial, NCT04061863). METHODS: We analyzed associations between tumor molecular profiles based on genomic (n = 76) and transcriptomic data (n = 58) and therapeutic efficacy. Patients who achieved progression-free survival (PFS) ≥ 6 months were defined as PFS6-responders and PFS6-nonresponders otherwise. FINDINGS: Analyses on tumor mutation burden (TMB) showed a tendency toward a favorable effect on efficacy, while several analyses related to homologous recombination deficiency (HRD) indicated a potentially negative impact on efficacy. Patients harboring TP53 mutations showed significantly poor PFS6 rate and PFS, which correlated with the enrichment of cell cycle-related signatures in PFS6-nonresponders. High antigen presentation gene set enrichment scores (≥ median) were significantly associated with longer PFS. Naïve B-cell and plasma cell proportions were considerably higher in long responders (≥ 18 months). INTERPRETATION: Genomic features including TMB, HRD, and TP53 mutations and transcriptomic features related to immune cell profiles and cell cycle may distinguish responders. Our findings provide insights for further exploring the combination regimen and its biomarkers in these tumors.

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.

Prognostic value of structural variants in early breast cancer patients.

Genomic analysis of structural variants(SVs) in breast cancer (BC) patients has been conducted, but the relationship between genomic alterations and BC prognosis remains unclear. We performed RNA sequencing of 297 early BC fresh-frozen tissues. We identified SVs using three tools (STAR.Arriba, STAR.fusion, and STAR.SEQR) with the COSMIC and Mitelman databases as guide references. We found a median of five to eight fusions per sample. In BC intrinsic subtypes, normal subtype had the fewest fusions (median: 1, interquartile range [IQR]: 0, 3) followed by luminal A (median: 5.5, IQR: 2.75, 10.25), luminal B (median: 9, IQR: 6, 16.5), HER2-enriched (median: 9, IQR: 6, 16.5) and basal (median 10, IQR: 6, 15.5) subtypes (p < 0.05). Intrachromosomal fusion was more frequent observed rather than interchromosomal fusion. In location, chromosome 17 had the most fusions followed by chromosome 1 and 11. When samples were divided into high and low fusion groups based on a cut-off value of 11 fusions, five-year event-free survival (5Y-EFS) was 68.1% in the high fusion group (n = 72) and 80.1% in the low fusion group (n = 125) (p = 0.024) while 75.6% among all patients (95% confidence interval: 0.699, 0.819). Among BC subtype, TNBCs with more fusions had shorter EFS compared to those with fewer fusions (5Y-EFS rate: 65.1% vs. 85.7%; p = 0.013) but no EFS differences were observed in other BC subtypes. ESTIMATE ImmuneScore was also associated with the number of fusions in TNBC (p < 0.005) and TNBCs with high ImmuneScore had better 5Y-EFS compared to those with low ImmuneScore (p = 0.041). In conclusion, diverse fusions were observed by BC subtype, and the number of fusions was associated with BC survival outcome and immune status in TNBC.

Neoadjuvant Chemotherapy Response in Triple-Negative Apocrine Carcinoma: Comparing Apocrine Morphology, Androgen Receptor, and Immune Phenotypes.

CONTEXT.­: Apocrine differentiation and androgen receptor (AR) positivity represent a specific subset of triple-negative breast cancer (TNBC) and are often considered potential prognostic or predictive factors. OBJECTIVE.­: To evaluate the response of TNBC to neoadjuvant chemotherapy (NAC) and to assess the impact of apocrine morphology, AR status, Ki-67 labeling index (Ki-67LI), and tumor-infiltrating lymphocytes (TILs). DESIGN.­: A total of 232 TNBC patients who underwent NAC followed by surgical resection in a single institute were analyzed. The study evaluated apocrine morphology and AR and Ki-67LI expression via immunohistochemistry from pre-NAC biopsy samples. Additionally, pre-NAC intratumoral TILs and stromal TILs (sTILs) were quantified from biopsies using a deep learning model. The response to NAC after surgery was assessed based on residual cancer burden. RESULTS.­: Both apocrine morphology and high AR expression correlated with lower Ki-67LI (P < .001 for both). Apocrine morphology was associated with lower postoperative pathologic complete response (pCR) rates after NAC (P = .02), but the difference in TILs between TNBC cases with and without apocrine morphology was not statistically significant (P = .09 for sTILs). In contrast, AR expression did not significantly affect pCR (P = .13). Pre-NAC TILs strongly correlated with postoperative pCR in TNBCs without apocrine morphology (P < .001 for sTILs), whereas TNBC with apocrine morphology demonstrated an indeterminate trend (P = .82 for sTILs). CONCLUSIONS.­: Although TIL counts did not vary significantly based on apocrine morphology, apocrine morphology itself was a more reliable predictor of NAC response than AR expression. Consequently, although apocrine morphology is a rare subtype of TNBC, its identification is clinically important.

Scalp Cooling in Preventing Persistent Chemotherapy-Induced Alopecia: A Randomized Controlled Trial.

PURPOSE: Current studies of the efficacy of scalp cooling are limited by short-term duration. Therefore, we conducted a randomized controlled trial to evaluate the efficacy of scalp cooling in reducing persistent chemotherapy-induced alopecia (PCIA) 6 months after chemotherapy. METHODS: We conducted an open-label randomized controlled trial comparing scalp cooling versus control in newly diagnosed patients with breast cancer stages I-III scheduled to receive neoadjuvant or adjuvant chemotherapy with curative intent between December 2020 and August 2021. Patients were randomly assigned (2:1 ratio) to scalp cooling or usual clinical practice. The primary outcome was PCIA 6 months after chemotherapy. Hair thickness and density were measured using Folliscope 5.0. CIA-related distress was assessed using the CIA distress scale (CADS), with a higher score reflecting higher stress. RESULTS: The proportion of patients with PCIA at 6 months was 13.5% (12/89) in the scalp-cooling group and 52.0% (26/50) in the control group. The average difference in the change in hair thickness from baseline between the scalp-cooling and control groups was 9.0 µm in favor of the intervention group. The average difference in the change in hair density between intervention and control at the end of the study was -3.3 hairs/cm2. At 6 months after chemotherapy, the average difference in the change in CADS score between the intervention and control groups was -3.2 points, reflecting reduced CIA-related stress in the intervention group. CONCLUSION: Scalp cooling reduced the incidence of PCIA, primarily by increasing hair thickness compared with control. Scalp cooling is helpful in promoting qualitative hair regrowth. Yet, further research is necessary to observe longer-term benefits of scalp cooling.

Neoadjuvant pembrolizumab+chemotherapy/adjuvant pembrolizumab for Early-Stage Triple-Negative breast cancer: Quality-of-Life results from randomized KEYNOTE-522 study.

BACKGROUND: In KEYNOTE-522 (NCT03036488), neoadjuvant pembrolizumab+chemotherapy then adjuvant pembrolizumab significantly improved pathological complete response and event-free survival vs neoadjuvant chemotherapy in early-stage triple-negative breast cancer (TNBC). We report patient-reported outcomes (PROs) from KEYNOTE-522. METHODS: Patients were randomized 2:1 to neoadjuvant pembrolizumab 200 mg or placebo every 3 weeks, plus 4 cycles of paclitaxel+carboplatin then 4 cycles of doxorubicin (or epirubicin)+cyclophosphamide. After surgery, patients received adjuvant pembrolizumab or placebo for up to 9 cycles. EORTC QLQ-30 and QLQ-BR23 were prespecified secondary objectives. Between-group differences in least squares (LS) mean change from baseline (day 1/cycle 1 in both neoadjuvant and adjuvant phases) to the prespecified latest time point with ≥60%/80% completion/compliance were assessed using a longitudinal model (no alpha error assigned). RESULTS: Week 21 (neoadjuvant phase) and week 24 (adjuvant phase) were the latest time points at which completion/compliance rates were ≥60%/80%. In the neoadjuvant phase, between-group differences (pembrolizumab+chemotherapy [N = 762] vs placebo+chemotherapy [N = 383]) in LS mean change from baseline to week 21 in QLQ-C30 GHS/QoL, emotional functioning, and physical functioning were -1.04 (95% CI, -3.46 to 1.38), -0.69 (95% CI, -3.13 to 1.75), and -2.85 (95% CI, -5.11 to - 0.60), respectively. In the adjuvant phase, between-group differences (pembrolizumab [N = 539] vs placebo [N = 308]) in LS mean change from baseline to week 24 were -0.41 (95% CI, -2.60 to 1.77), -0.60 (95% CI, -2.99 to 1.79), and -1.57 (95% CI, -3.36 to 0.21). CONCLUSIONS: No substantial differences in PRO assessments were observed between neoadjuvant pembrolizumab+chemotherapy followed by adjuvant pembrolizumab vs neoadjuvant placebo+chemotherapy in early-stage TNBC. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03036488.

Inhibition of lysine acetyltransferase KAT6 in ER+HER2- metastatic breast cancer: a phase 1 trial.

Inhibition of histone lysine acetyltransferases (KATs) KAT6A and KAT6B has shown antitumor activity in estrogen receptor-positive (ER+) breast cancer preclinical models. PF-07248144 is a selective catalytic inhibitor of KAT6A and KAT6B. In the present study, we report the safety, pharmacokinetics (PK), pharmacodynamics, efficacy and biomarker results from the first-in-human, phase 1 dose escalation and dose expansion study (n = 107) of PF-07248144 monotherapy and fulvestrant combination in heavily pretreated ER+ human epidermal growth factor receptor-negative (HER2-) metastatic breast cancer (mBC). The primary objectives of assessing the safety and tolerability and determining the recommended dose for expansion of PF-07248144, as monotherapy and in combination with fulvestrant, were met. Secondary endpoints included characterization of PK and evaluation of antitumor activity, including objective response rate (ORR) and progression-free survival (PFS). Common treatment-related adverse events (any grade; grades 3-4) included dysgeusia (83.2%, 0%), neutropenia (59.8%, 35.5%) and anemia (48.6%, 13.1%). Exposure was approximately dose proportional. Antitumor activity was observed as monotherapy. For the PF-07248144-fulvestrant combination (n = 43), the ORR (95% confidence interval (CI)) was 30.2% (95% CI = 17.2-46.1%) and the median PFS was 10.7 (5.3-not evaluable) months. PF-07248144 demonstrated a tolerable safety profile and durable antitumor activity in heavily pretreated ER+HER2- mBC. These findings establish KAT6A and KAT6B as druggable cancer targets, provide clinical proof of concept and reveal a potential avenue to treat mBC. clinicaltrial.gov registration: NCT04606446 .

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.

A 10-Gene Signature to Predict the Prognosis of Early-Stage Triple-Negative Breast Cancer.

Purpose: Triple-negative breast cancer (TNBC) is a particularly challenging subtype of breast cancer, with a poorer prognosis compared to other subtypes. Unfortunately, unlike luminal type cancers, there is no validated biomarker to predict the prognosis of patients with early-stage TNBC. Accurate biomarkers are needed to establish effective therapeutic strategies. Materials and Methods: In this study, we analyzed gene expression profiles of tumor samples from 184 TNBC patients (training cohort, n=76; validation cohort, n=108) using RNA sequencing. Results: By combining weighted gene expression, we identified a 10-gene signature (DGKH, GADD45B, KLF7, LYST, NR6A1, PYCARD, ROBO1, SLC22A20P, SLC24A3, and SLC45A4) that stratified patients by risk score with high sensitivity (92.31%), specificity (92.06%), and accuracy (92.11%) for invasive disease-free survival. The 10-gene signature was validated in a separate institution cohort and supported by meta-analysis for biological relevance to well-known driving pathways in TNBC. Furthermore, the 10-gene signature was the only independent factor for invasive disease-free survival in multivariate analysis when compared to other potential biomarkers of TNBC molecular subtypes and T-cell receptor ß diversity. 10-gene signature also further categorized patients classified as molecular subtypes according to risk scores. Conclusion: Our novel findings may help address the prognostic challenges in TNBC and the 10-gene signature could serve as a novel biomarker for risk-based patient care.

Trastuzumab deruxtecan versus treatment of physician's choice in patients with HER2-positive metastatic breast cancer (DESTINY-Breast02): patient-reported outcomes from a randomised, open-label, multicentre, phase 3 trial.

BACKGROUND: In DESTINY-Breast02, patients with HER2-positive unresectable or metastatic breast cancer who received trastuzumab deruxtecan demonstrated superior progression-free and overall survival compared with those receiving treatment of physician's choice. We present the patient-reported outcomes (PROs) and hospitalisation data. METHODS: In this randomised, open-label, phase 3 trial conducted at 227 clinical sites globally, enrolled patients had to be aged 18 years or older with HER2-positive unresectable or metastatic breast cancer that had progressed on trastuzumab emtansine and had an Eastern Cooperative Oncology Group performance status of 0 or 1. Patients were randomly assigned (2:1) using block randomisation (block size of 3) to receive trastuzumab deruxtecan (5·4 mg/kg intravenously once every 21 days) or treatment of physician's choice by an independent biostatistician using an interactive web-based system. Patients and investigators remained unmasked to treatment. Treatment of physician's choice was either capecitabine (1250 mg/m2 orally twice per day on days 1-14) plus trastuzumab (8 mg/kg intravenously on day 1 then 6 mg/kg once per day) or capecitabine (1000 mg/m2) plus lapatinib (1250 mg orally once per day on days 1-21), with a 21-day schedule. The primary endpoint, which was progression-free survival based on blinded independent central review, has previously been reported. PROs were assessed in the full analysis set (all patients randomly assigned to the study) using the oncology-specific European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 (EORTC QLQ-C30), breast cancer-specific EORTC Quality of Life Questionnaire Breast 45 (QLQ-BR45), and the generic HRQoL EQ-5D-5L questionnaire. Analyses included change from baseline and time to definitive deterioration for PRO variables of interest and hospitalisation-related endpoints. This study is registered with ClinicalTrials.gov, NCT03523585, and is closed to recruitment. FINDINGS: Between Sept 6, 2018, and Dec 31, 2020, 608 patients were randomly assigned to receive either trastuzumab deruxtecan (n=406; two did not receive treatment) or treatment of physician's choice (n=202; seven did not receive treatment). Overall, 603 patients (99%) were female and five (<1%) were male. The median follow-up was 21·5 months (IQR 15·2-28·4) in the trastuzumab deruxtecan group and 18·6 months (IQR 8·8-26·0) in the treatment of physician's choice group. Median treatment duration was 11·3 months (IQR 6·2-20·5) in the trastuzumab deruxtecan group and approximately 4·5 months in the treatment of physician's choice group (4·4 months [IQR 2·5-8·7] with trastuzumab; 4·6 months [2·1-8·9] with capecitabine; and 4·5 months [2·1-10·6] with lapatinib). Baseline EORTC QLQ-C30 global health status (GHS) scores were similar with trastuzumab deruxtecan (n=393) and treatment of physician's choice (n=187), and remained stable with no clinically meaningful change (defined as ≥10-point change from baseline) over time. Median time to definitive deterioration was delayed with trastuzumab deruxtecan compared with treatment of physician's choice for the primary PRO variable EORTC QLQ-C30 GHS (14·1 months [95% CI 10·4-18·7] vs 5·9 months [4·3-7·9]; HR 0·5573 [0·4376-0·7099], p<0·0001) and all other prespecified PROs (EORTC QLQ-C30 subscales, EORTC QLQ-BR45 arm and breast symptoms, and EQ-5D-5L visual analogue scale). Patient hospitalisation rates were similar in the trastuzumab deruxtecan (92 [23%] of 406) and treatment of physician's choice (41 [20%] of 202) groups; however, median time to hospitalisation was 133 days (IQR 56-237) with trastuzumab deruxtecan versus 83 days (30-152) with treatment of physician's choice. INTERPRETATION: Overall, GHS and quality of life were maintained for both treatment groups, with prespecified PRO variables favouring trastuzumab deruxtecan over treatment of physician's choice, suggesting that despite a longer treatment duration, there was no detrimental impact on patient health-related quality of life with trastuzumab deruxtecan. When considered with efficacy and safety data from DESTINY-Breast02, these results support the overall benefit of trastuzumab deruxtecan for patients with HER2-positive unresectable or metastatic breast cancer previously treated with trastuzumab emtansine. FUNDING: Daiichi Sankyo and AstraZeneca.

Outcomes in Nonmetastatic Hormone Receptor-Positive HER2-Negative Pure Mucinous Breast Cancer: A Multicenter Cohort Study.

BACKGROUND: Although considered a favorable subtype, pure mucinous breast cancer (PMBC) can recur, and evidence for adjuvant therapy is limited. We aimed to compare outcomes of nonmetastatic PMBC with invasive ductal carcinoma (IDC) and invasive lobular carcinoma (ILC) to address these uncertainties. METHODS: Individual patient-level data from 6 centers on stage I-III hormone receptor-positive and HER2-negative PMBC, IDC, and ILC were used to analyze recurrence-free interval (RFI), recurrence-free survival (RFS), and overall survival (OS), and to identify prognostic factors for PMBC. RESULTS: Data from 20,684 IDC cases, 1,475 ILC cases, and 943 PMBC cases were used. Median follow-up was 6.6 years. Five-year RFI, RFS, and OS for PMBC were 96.1%, 94.9%, and 98.1%, respectively. On multivariable Cox regression, PMBC demonstrated superior RFI (hazard ratio [HR], 0.59; 95% CI, 0.43-0.80), RFS (HR, 0.70; 95% CI, 0.56-0.89), and OS (HR, 0.71; 95% CI, 0.53-0.96) compared with IDC. ILC showed comparable outcomes to IDC. Fewer than half (48.7%) of recurrences in PMBC were distant, which was a lower rate than for IDC (67.3%) and ILC (80.6%). In contrast to RFI, RFS events were driven more by non-breast cancer deaths in older patients. Significant prognostic factors for RFI among PMBC included positive lymph node(s) (HR, 2.42; 95% CI, 1.08-5.40), radiotherapy (HR, 0.44; 95% CI, 0.23-0.85), and endocrine therapy (HR, 0.25; 95% CI, 0.09-0.70). No differential chemotherapy associations with outcomes were detected across PMBC subgroups by nodal stage, tumor size, and age. A separate SEER database analysis also did not find any association of improved survival with adjuvant chemotherapy in these subgroups. CONCLUSIONS: Compared with IDC, PMBC demonstrated superior RFI, RFS, and OS. Lymph node negativity, adjuvant radiotherapy, and endocrine therapy were associated with superior RFI. Adjuvant chemotherapy was not associated with better outcomes.