Comparative efficacy and safety of CDK4/6 inhibitors combined with endocrine therapies for HR+/HER2-breast cancer: Systematic review and network meta-analysis.

Background: In recent years, the combination of targeted drugs, such as Cyclin-dependent kinase 4/6 (CDK4/6) inhibitors, with endocrine therapy (ET), has emerged as a new research focus in the treatment of hormone receptor-positive (HR+) human epidermal growth factor receptor 2 negative (HER2-) breast cancer. This network meta-analysis aimed to systematically evaluate the efficacy and safety of CDK4/6 inhibitors combined with ET for HR+/HER2-breast cancer. Methods: A systematic search was conducted across PubMed, Web of Science, Cochrane Library, and GeenMedical databases to identify randomized controlled trials investigating the use of CDK4/6 inhibitors in combination with endocrine therapy for the treatment of HR+/HER2-breast cancer. The search period spanned from the inception of each database up to February 29, 2024. Data analysis was conducted using Stata 14.0 and R 4.1.0 software. Results: A total of 20 randomized controlled trials (RCTs) were included in this study, investigating the effectiveness of four CDK4/6 inhibitors-Abemaciclib, Dalpiciclib, Ribociclib, and Palbociclib-when combined with ET for the treatment of HR+/HER2-breast cancer. The results indicated that Abemaciclib + ET, Dalpiciclib + ET, Palbociclib + ET, and Ribociclib + ET exhibited similar therapeutic effects in terms of improving objective response rate (ORR), disease control rate (DCR) and reducing the occurrence of fatigue, all of which were superior to ET alone. However, in terms of prolonging progression-free survival (PFS) and overall survival (OS), Dalpiciclib + ET significantly improved PFS compared to Ribociclib + ET, Palbociclib + ET, Abemaciclib and Palbociclib. Ribociclib + ET significantly improved OS compared to Palbociclib + ET. Regarding overall adverse reaction events (AREs), Dalpiciclib + ET had a higher incidence compared to Ribociclib + ET. The incidence of neutropenia caused by Dalpiciclib + ET was significantly higher compared to Palbociclib + ET, Ribociclib + ET, Abemaciclib, and Palbociclib. Abemaciclib + ET demonstrated the worst safety profile concerning diarrhea. Conclusion: Abemaciclib + ET likely represents the most effective option in terms of therapeutic effects, but it is prone to causing diarrhea and fatigue. On the other hand, Dalpiciclib + ET likely demonstrates the best efficacy in terms of PFS but exhibits the poorest safety profile, particularly in relation to neutropenia. Therefore, clinicians should exercise increased vigilance in monitoring and managing adverse effects when prescribing Abemaciclib + ET and Dalpiciclib + ET.

Comprehensive genomic profiling of ESR1, PIK3CA, AKT1, and PTEN in HR(+)HER2(-) metastatic breast cancer: prevalence along treatment course and predictive value for endocrine therapy resistance in real-world practice.

BACKGROUND: The treatment landscape for HR(+)HER2(-) metastatic breast cancer (MBC) is evolving for patients with ESR1 mutations (mut) and PI3K/AKT pathway genomic alterations (GA). We sought to inform clinical utility for comprehensive genomic profiling (CGP) using tissue (TBx) and liquid biopsies (LBx) in HR(+)HER2(-) MBC. METHODS: Records from a de-identified breast cancer clinicogenomic database for patients who underwent TBx/LBx testing at Foundation Medicine during routine clinical care at ~ 280 US cancer clinics between 01/2011 and 09/2023 were assessed. GA prevalence [ESR1mut, PIK3CAmut, AKT1mut, PTENmut, and PTEN homozygous copy loss (PTENloss)] were calculated in TBx and LBx [stratified by ctDNA tumor fraction (TF)] during the first three lines of therapy. Real-world progression-free survival (rwPFS) and overall survival (rwOS) were compared between groups by Cox models adjusted for prognostic factors. RESULTS: ~ 60% of cases harbored 1 + GA in 1st-line TBx (1266/2154) or LBx TF ≥ 1% (80/126) and 26.5% (43/162) in LBx TF < 1%. ESR1mut was found in 8.1% TBx, 17.5% LBx TF ≥ 1%, and 4.9% LBx TF < 1% in 1st line, increasing to 59% in 3rd line (LBx TF ≥ 1%). PTENloss was detected at higher rates in TBx (4.3%) than LBx (1% in TF ≥ 1%). Patients receiving 1st-line aromatase inhibitor + CDK4/6 inhibitor (n = 573) with ESR1mut had less favorable rwPFS and rwOS versus ESR1 wild-type; no differences were observed for fulvestrant + CDK4/6 inhibitor (n = 348). CONCLUSION: Our study suggests obtaining TBx for CGP at time of de novo/recurrent diagnosis, followed by LBx for detecting acquired GA in 2nd + lines. Reflex TBx should be considered when ctDNA TF < 1%.

Identifying drivers of first-line HR+/HER2- metastatic breast cancer treatment choices.

Aim: Assess factors associated with first-line (1L) treatment for HR+/HER2- metastatic breast cancer. Materials & methods: A cross-sectional survey of 250 US oncologists was conducted. Correlations were calculated between treatment class and demographics, treatment perceptions and other clinical/nonclinical characteristics. Results: Efficacy and safety/tolerability were critical in oncologists' 1L decision-making. CDK4/6i use positively correlated with proportion of Medicare and postmenopausal patients (r = 0.54-0.67). Chemotherapy use demonstrated positive correlations with perimenopausal and premenopausal patients and symptom burden (r = 0.31-0.42). Aromatase inhibitor (AI) monotherapy correlated positively with anticipated treatment compliance (r = 0.42). Conclusion: Efficacy and safety/tolerability were most important to 1L decision-making. Clinical characteristics corresponded with CDK4/6i and chemotherapy use. Anticipated compliance was associated with AI monotherapy use.

Patients in the USA with a certain type of metastatic breast cancer (mBC, i.e., HR+/HER2−) might get chemotherapy or hormone therapy alone instead of new and potentially better medicines called cyclin-dependent kinase 4/6 inhibitors (CDK4/6i) as their first treatment.Researchers wanted to understand how US cancer specialists decided the first treatment for this type of mBC. In a survey of 250 cancer specialists, researchers looked at different factors that might influence decision-making, including patient characteristics, doctors' opinions about the treatments and other medical and non-medical features. This study also examined the connections between these factors and the cancer specialists' choice of first treatment.Researchers found that cancer specialists care most about how well a treatment works and how safe it is when choosing the first treatment for HR+/HER2− mBC. They are more likely to use CDK4/6i if their patients have Medicare coverage or are older (i.e., women who have been through menopause). Chemotherapy is chosen if their patients are younger (i.e., women who are near and before menopause) or have more symptoms. Cancer specialists tend to choose first treatment with hormone therapy alone if they think their patients have a hard time following their treatment plan. The results showed that patient characteristics, doctors' opinions of treatments and other medical and non-medical factors play a role in choosing treatment for HR+/HER2− mBC. By understanding these factors, researchers can work toward improving treatment choices for patients with this type of mBC.

Health-related quality of life with sacituzumab govitecan in HR+/HER2- metastatic breast cancer in the phase III TROPiCS-02 trial.

BACKGROUND: The TROPiCS-02 study (NCT03901339) demonstrated that sacituzumab govitecan (SG) has superior clinical outcomes over treatment of physician's choice (TPC) chemotherapy in patients with hormone receptor-positive, human epidermal growth factor 2 receptor-negative (HR+/HER2-) metastatic breast cancer (mBC). Here, we present health-related quality of life (HRQoL) patient-reported outcome (PRO) findings from this study. PATIENTS AND METHODS: Eligible adults with HR+/HER2- mBC who previously received a taxane, endocrine-based therapy, a CDK4/6 inhibitor, and 2-4 lines of chemotherapy were randomized 1:1 to receive SG or TPC until progression or unacceptable toxicity. PROs were assessed at baseline and on day 1 of each cycle, using the European Organization for Research and Treatment of Cancer Quality-of-Life Core 30 (EORTC QLQ-C30), EQ-5D-5L, and PRO Common Terminology Criteria for Adverse Events (PRO-CTCAE). RESULTS: Compared to TPC, overall least square mean change from baseline was significantly better for SG for physical functioning and dyspnea, but worse for diarrhea. Time to first clinically meaningful worsening or death was significantly longer for SG in global health status/quality of life, physical functioning, fatigue, emotional functioning, dyspnea, insomnia, and financial difficulties of the EORTC QLQ-C30 and the EQ-VAS, but longer for TPC in diarrhea. Few patients in both arms reported experiencing any worsening to level 3 or 4 treatment-related symptomatic events during treatment, as assessed by 16 PRO-CTCAE items, except for diarrhea frequency and amount of hair loss, which favored TPC. CONCLUSIONS: SG was associated with an HRQoL benefit in most symptoms and functioning, compared with TPC. This supports the favorable profile of SG as a treatment option for patients with pretreated HR+/HER2- mBC.

Systematic literature review of real-world evidence for treatments in HR+/HER2- second-line LABC/mBC after first-line treatment with CDK4/6i.

BACKGROUND: Cyclin-dependent kinase 4 and 6 inhibitors (CDK4/6i) combined with endocrine therapy (ET) are currently recommended by the National Comprehensive Cancer Network (NCCN) guidelines and the European Society for Medical Oncology (ESMO) guidelines as the first-line (1 L) treatment for patients with hormone receptor-positive, human epidermal growth factor receptor 2-negative, locally advanced/metastatic breast cancer (HR+/HER2- LABC/mBC). Although there are many treatment options, there is no clear standard of care for patients following 1 L CDK4/6i. Understanding the real-world effectiveness of subsequent therapies may help to identify an unmet need in this patient population. This systematic literature review qualitatively synthesized effectiveness and safety outcomes for treatments received in the real-world setting after 1 L CDK4/6i therapy in patients with HR+/ HER2- LABC/mBC. METHODS: MEDLINE®, Embase, and Cochrane were searched using the Ovid® platform for real-world evidence studies published between 2015 and 2022. Grey literature was searched to identify relevant conference abstracts published from 2019 to 2022. The review was conducted in accordance with PRISMA guidelines (PROSPERO registration: CRD42023383914). Data were qualitatively synthesized and weighted average median real-world progression-free survival (rwPFS) was calculated for NCCN/ESMO-recommended post-1 L CDK4/6i treatment regimens. RESULTS: Twenty records (9 full-text articles and 11 conference abstracts) encompassing 18 unique studies met the eligibility criteria and reported outcomes for second-line (2 L) treatments after 1 L CDK4/6i; no studies reported disaggregated outcomes in the third-line setting or beyond. Sixteen studies included NCCN/ESMO guideline-recommended treatments with the majority evaluating endocrine-based therapy; five studies on single-agent ET, six studies on mammalian target of rapamycin inhibitors (mTORi) ± ET, and three studies with a mix of ET and/or mTORi. Chemotherapy outcomes were reported in 11 studies. The most assessed outcome was median rwPFS; the weighted average median rwPFS was calculated as 3.9 months (3.3-6.0 months) for single-agent ET, 3.6 months (2.5-4.9 months) for mTORi ± ET, 3.7 months for a mix of ET and/or mTORi (3.0-4.0 months), and 6.1 months (3.7-9.7 months) for chemotherapy. Very few studies reported other effectiveness outcomes and only two studies reported safety outcomes. Most studies had heterogeneity in patient- and disease-related characteristics. CONCLUSIONS: The real-world effectiveness of current 2 L treatments post-1 L CDK4/6i are suboptimal, highlighting an unmet need for this patient population.

Real-world effectiveness of palbociclib in HR+/HER2- metastatic breast cancer: a literature review.

Approximately 70% of newly diagnosed breast cancers are of the HR+/HER2- subtype. For the treatment of patients with HR+/HER2- metastatic breast cancer, current guidelines recommend the use of a CDK4/6 inhibitor (palbociclib, ribociclib or abemaciclib) in combination with endocrine therapy. In this review we assess existing literature concerning real-world effectiveness of palbociclib. Survival outcomes in terms of progression-free survival and overall survival are discussed and compared among the included real-world studies and in relation to the phase III PALOMA trials.

About 70% of newly diagnosed breast cancers belong to a specific subgroup called hormone receptor positive (HR+)/Human epidermal growth factor receptor 2 negative (HER2-). In cases with metastatic disease, doctors recommend a treatment approach combining drugs such as palbociclib along with hormonal therapy. Our review evaluates how palbociclib performs in patients in real-world practice situations, beyond clinical trial settings. We looked at two key measures: how long the cancer stays controlled (progression-free survival) and overall survival. The results from these real-world studies are discussed and compared to findings in clinical trials.

Calcification-associated molecular traits and therapeutic strategies in hormone receptor-positive HER2-negative breast cancer.

OBJECTIVE: Mammographic calcifications are a common feature of breast cancer, but their molecular characteristics and treatment implications in hormone receptor-positive (HR+)/human epidermal growth factor receptor 2-negative (HER2-) breast cancer remain unclear. METHODS: We retrospectively collected mammography records of an HR+/HER2- breast cancer cohort (n = 316) with matched clinicopathological, genomic, transcriptomic, and metabolomic data. On the basis of mammographic images, we grouped tumors by calcification status into calcification-negative tumors, tumors with probably benign calcifications, tumors with calcification of low-moderate suspicion for maligancy and tumors with calcification of high suspicion for maligancy. We then explored the molecular characteristics associated with each calcification status across multiple dimensions. RESULTS: Among the different statuses, tumors with probably benign calcifications exhibited elevated hormone receptor immunohistochemical staining scores, estrogen receptor (ER) pathway activation, lipid metabolism, and sensitivity to endocrine therapy. Tumors with calcifications of high suspicion for malignancy had relatively larger tumor sizes, elevated lymph node metastasis incidence, Ki-67 staining scores, genomic instability, cell cycle pathway activation, and may benefit from cyclin-dependent kinase 4 and 6 (CDK4/6) inhibitors. CONCLUSIONS: Our research established links between tumor calcifications and molecular features, thus proposing potential precision treatment strategies for HR+/HER2- breast cancer.

First-line therapy with palbociclib in patients with advanced HR+/HER2- breast cancer: The real-life study PALBOSPAIN.

PURPOSE: To evaluate the efficacy and safety of first-line therapy with palbociclib in a Spanish cohort treated after palbociclib approval. METHODS: PALBOSPAIN is an observational, retrospective, multicenter study evaluating real-world patterns and outcomes with 1 L palbociclib in men and women (any menopausal status) with advanced HR+/HER2- BC diagnosed between November 2017 and November 2019. The primary endpoint was real-world progression-free survival (rw-PFS). Secondary endpoints included overall survival (OS), the real-world response rate (rw-RR), the clinical benefit rate, palbociclib dose reduction, and safety. RESULTS: A total of 762 patients were included. The median rw-PFS and OS were 24 months (95% CI 21-27) and 42 months (40-not estimable [NE]) in the whole population, respectively. By cohort, the median rw-PFS and OS were as follows: 28 (95% CI 23-39) and 44 (95% CI 38-NE) months in patients with de novo metastatic disease, 13 (95% CI 11-17) and 36 months (95% CI 31-41) in patients who experienced relapse < 12 months after the end of ET, and 31 months (95% CI 26-37) and not reached (NR) in patients who experienced relapse > 12 months after the end of ET. rw-PFS and OS were longer in patients with oligometastasis and only one metastatic site and those with non-visceral disease. The most frequent hematologic toxicity was neutropenia (72%; grade ≥ 3: 52.5%), and the most common non-hematologic adverse event was asthenia (38%). CONCLUSION: These findings, consistent with those from clinical trials, support use of palbociclib plus ET as 1 L for advanced BC in the real-world setting, including pre-menopausal women and men. TRIAL REGISTRATION NUMBER: NCT04874025 (PALBOSPAIN). Date of registration: 04/30/2021 retrospectively registered.

Preventing alpelisib-related hyperglycaemia in HR+/HER2-/PIK3CA-mutated advanced breast cancer using metformin (METALLICA): a multicentre, open-label, single-arm, phase 2 trial.

Background: Hyperglycaemia is an early and frequent adverse event during alpelisib treatment. METALLICA aimed to evaluate prophylactic metformin to prevent or reduce hyperglycaemia occurrence in patients with HR+/HER2-/PIK3CA-mutated advanced breast cancer (ABC). Methods: Between August 13th, 2020 and March 23rd, 2022, this 2-cohort, phase 2, multicentre, single-arm trial (NCT04300790) enrolled patients with HR+/HER2-/PIK3CA-mutated ABC: cohort A, normal glycaemia (fasting plasma glucose <100 mg/dL [<5.6 mmol/L] and HbA1c <5.7%), and cohort B, prediabetes (fasting plasma glucose 100-140 mg/dL [5.6-7.8 mmol/L] and/or haemoglobin A1C [HbA1c] 5.7-6.4%). Participants were at least 18 years old, with Eastern Cooperative Oncology Group performance status of 0-1, and up to two prior lines of endocrine therapy (ET) for ABC. Alpelisib plus ET were administered in 28-day cycles after initiation of prophylactic metformin plus ET. Primary endpoint was the incidence of grade 3-4 hyperglycaemia over the first 8 weeks. Secondary endpoints included safety, progression-free survival (PFS), objective response rate (ORR), and clinical benefit rate (CBR). The primary objective for cohort A and B is met with ≤7 (14.6%) and ≤4 (20%) patients with grade 3-4 hyperglycaemia over the first 8 weeks, respectively. Findings: 233 patients were screened, and 68 (20.2%) patients were enrolled in cohorts A (n = 48) and B (n = 20). Median follow-up was 7.8 months (IQR 1.4-19.6). Over the first 8 weeks, one (2.1%) of 48 patients in cohort A (95% CI: 0.5-11.1; P < 0.0001), and three (15.0%) of 20 patients in cohort B (95% CI: 5.6-37.8; P = 0.016) had grade 3-4 hyperglycaemia. Serious treatment-related adverse events occurred in seven patients (10.3%). The most common were rash (two [2.9%]), vomiting (two [2.9%]), and diarrhoea (two [2.9%]). Discontinuation of alpelisib caused by AEs was reported in nine patients (13.2%), none caused by hyperglycaemia. At data cutoff (15 June, 2022), no treatment-related deaths were observed. In the full analysis set, median PFS was 7.3 months (95% CI: 5.9-not reached), ORR was 20.6% (95% CI: 11.7-32.1%), and CBR was 52.9% (95% CI: 40.4-65.2). Interpretation: In HR+/HER2-/PIK3CA-mutated ABC, prophylactic metformin before alpelisib plus endocrine treatment has low incidence and severity of alpelicib-induced hyperglycaemia. Funding: Novartis Pharmaceuticals.

Disease-free survival as a surrogate for overall survival in HR+/HER2- early breast cancer: A correlation analysis.

BACKGROUND: Overall survival (OS) is a universally accepted measure of clinical benefit; however, prolonged follow-up is needed to observe sufficient events. Disease-free survival (DFS) has been widely adopted as a primary endpoint for early breast cancer (EBC) trials, as follow-up is comparatively shorter. Here, we present an analysis evaluating DFS as a surrogate for OS for adjuvant treatment of hormone receptor-positive/human epidermal growth factor receptor 2-negative (HR+/HER2-) EBC. METHODS: A systematic literature review which included randomized controlled trials (RCTs) with ≥80% of adult patients with HR+/HER2- EBC was conducted. The RCTs evaluated various systemic therapeutic categories; key inclusion criteria included reporting of DFS and OS hazard ratios (HRs) and mature OS data. Spearman rank correlation and weighted linear regression analyses evaluated DFS and OS HR correlation. A scenario analysis tested base-case analysis robustness, and a parallel analysis using patient-level data was conducted. RESULTS: The base case (N = 14 RCTs) showed an unweighted Spearman coefficient of 0.81 between OS and DFS (weighted: 0.81), with 84% of the variability in OS explained by DFS differences (R2 from weighted regression). The surrogate threshold effect (Burzykowski T, Buyse M. Pharm Stat. 2006;5:173-186) was 0.82 for DFS/OS HR. Scenario analysis (n = 9 RCTs), which excluded chemotherapy trials, and patient-level analysis using FACE trial data were consistent with the base-case analysis. CONCLUSIONS: These analyses support DFS as a reliable surrogate endpoint for OS in adjuvant HR+/HER2- EBC trials. Using DFS as a surrogate measure will permit timelier access to novel treatments for patients with HR+/HER2- EBC.

A risk analysis of alpelisib-induced hyperglycemia in patients with advanced solid tumors and breast cancer.

BACKGROUND: Hyperglycemia is an on-target effect of PI3Kα inhibitors. Early identification and intervention of treatment-induced hyperglycemia is important for improving management of patients receiving a PI3Kα inhibitor like alpelisib. Here, we characterize incidence of grade 3/4 alpelisib-related hyperglycemia, along with time to event, management, and outcomes using a machine learning model. METHODS: Data for the risk model were pooled from patients receiving alpelisib ± fulvestrant in the open-label, phase 1 X2101 trial and the randomized, double-blind, phase 3 SOLAR-1 trial. The pooled population (n = 505) included patients with advanced solid tumors (X2101, n = 221) or HR+/HER2- advanced breast cancer (SOLAR-1, n = 284). External validation was performed using BYLieve trial patient data (n = 340). Hyperglycemia incidence and management were analyzed for SOLAR-1. RESULTS: A random forest model identified 5 baseline characteristics most associated with risk of developing grade 3/4 hyperglycemia (fasting plasma glucose, body mass index, HbA1c, monocytes, age). This model was used to derive a score to classify patients as high or low risk for developing grade 3/4 hyperglycemia. Applying the model to patients treated with alpelisib and fulvestrant in SOLAR-1 showed higher incidence of hyperglycemia (all grade and grade 3/4), increased use of antihyperglycemic medications, and more discontinuations due to hyperglycemia (16.7% vs. 2.6% of discontinuations) in the high- versus low-risk group. Among patients in SOLAR-1 (alpelisib + fulvestrant arm) with PIK3CA mutations, median progression-free survival was similar between the high- and low-risk groups (11.0 vs. 10.9 months). For external validation, the model was applied to the BYLieve trial, for which successful classification into high- and low-risk groups with shorter time to grade 3/4 hyperglycemia in the high-risk group was observed. CONCLUSIONS: A risk model using 5 clinically relevant baseline characteristics was able to identify patients at higher or lower probability for developing alpelisib-induced hyperglycemia. Early identification of patients who may be at higher risk for hyperglycemia may improve management (including monitoring and early intervention) and potentially lead to improved outcomes. REGISTRATION: ClinicalTrials.gov: NCT01219699 (registration date: October 13, 2010; retrospectively registered), ClinicalTrials.gov: NCT02437318 (registration date: May 7, 2015); ClinicalTrials.gov: NCT03056755 (registration date: February 17, 2017).

Clinical management, monitoring, and prophylaxis of adverse events of special interest associated with datopotamab deruxtecan.

Antibody drug conjugates (ADCs) are an emerging class of treatments designed to improve efficacy and decrease toxicity compared with other systemic therapies through the selective delivery of cytotoxic agents to tumor cells. Datopotamab deruxtecan (Dato-DXd) is a novel ADC comprising a topoisomerase I inhibitor payload and a monoclonal antibody directed to trophoblast cell-surface antigen 2 (TROP2), a protein that is broadly expressed in several types of solid tumors. Dato-DXd is being investigated across multiple solid tumor indications. In the ongoing, first-in-human TROPION-PanTumor01 phase I study (ClinicalTrials.gov: NCT03401385), encouraging and durable antitumor activity and a manageable safety profile was demonstrated in patients with advanced/metastatic hormone receptor-positive/human epidermal growth factor receptor2-negative breast cancer (HR+/HER2- BC), triple-negative breast cancer (TNBC), and non-small cell lung cancer (NSCLC). Improved understanding of the adverse events (AEs) that are associated with Dato-DXd and their optimal management is essential to ensure safe and successful administration. Interstitial lung disease/pneumonitis, infusion-related reactions, oral mucositis/stomatitis, and ocular surface events have been identified as AEs of special interest (AESIs) for which appropriate prevention, monitoring, and management is essential. This article summarizes the incidence of AESIs among patients with HR+/HER2- BC, TNBC, and NSCLC reported in TROPION-PanTumor01. We report our recommendations for AESI prophylaxis, early detection, and management, using experience gained from treating AESIs that occur with Dato-DXd in clinical trials.

Cost-effectiveness comparison of dalpiciclib and abemaciclib combined with an aromatase inhibitor as first-line treatment for HR+/HER2- advanced breast cancer.

OBJECTIVES: CDK4/6 inhibitors dalpiciclib and abemaciclib have been approved by the Chinese National Medical Products Administration as first-line treatment for postmenopausal females with hormone receptor-positive (HR+) and human epidermal growth factor receptor-2 negative (HER2-) advanced breast cancer (ABC). We aimed to assess the cost-effectiveness of dalpiciclib plus letrozole/anastrozole (non-steroidal aromatase inhibitor [NSAI]) compared with abemaciclib plus NSAI as a first-line treatment for HR+/HER2- ABC in China. METHODS: We constructed a Markov model with three health states to evaluate health and economic outcomes of first-line treatment with dalpiciclib plus NSAI and abemaciclib plus NSAI for HR+/HER2- ABC. Efficacy data was obtained from MONARCH3 and DAWNA-2 trials. Quality-adjusted life-years (QALYs) and incremental cost-effectiveness ratios (ICERs) were calculated. RESULTS: Compared with abemaciclib plus NSAI, dalpiciclib plus NSAI resulted in 4.27 additional QALYs, with an ICER of $14827.4/QALY. At a willingness-to-pay threshold of 3 times gross domestic product per capita in China for 2023 ($37721.5/QALY), the cost-effectiveness probability of dalpiciclib plus NSAI was 77.42%. CONCLUSIONS: From the perspective of Chinese payers, dalpiciclib plus NSAI appears to be a cost-effective strategy compared with abemaciclib plus NSAI for the first-line treatment of patients with HR+/HER2- ABC in China. CLINICAL TRIAL REGISTRATION: MONARCH3, www.clinicaltrials.gov, identifier is NCT02246621 and DAWNA-2, www.clinicaltrials.gov, identifier is NCT03966898.

Concurrent neoadjuvant endocrine therapy with chemotherapy in HR+HER2- breast cancer: a systematic review and meta-analysis.

The role of simultaneous neoadjuvant endocrine therapy in chemotherapy in HR+HER2- breast cancer continues to be controversial. This systematic review and meta-analysis was conducted to further evaluate the effectiveness and safety of this strategy for HR+HER2- breast cancer patients. Trials in which HR+HER2- breast cancer patients were randomly assigned to either single or simultaneous endocrine-assisted neoadjuvant chemotherapy were eligible for inclusion. The prime endpoint was the pathological complete response (pCR) rate. The clinical response (complete clinical response: CR, partial response: PR) and safety were secondary endpoints. A random effect model was used for statistical analysis. A total of 690 patients from five trials were included. PCR rate was 10.43% in the concomitant endocrine group and 7.83% in control group (OR=1.37, 95%CI 0.72-2.60, P=0.34). The CR rate was 15.50% for the concomitant endocrine group and 10.26% for the control group. (OR=1.61, 95%CI 0.99-2.61, P=0.05). ORR (CR+PR) was significantly higher in the simultaneous endocrine group compared to the control group (79.53% (272/342) vs. 70.09% (239/341) , OR=1.70, 95%CI 1.19-2.43, P=0.004) and the meta-analysis approach showed no heterogeneity (I2 = 0%, P=0.54) . Tamoxifen concurrent with chemotherapy could increase the frequency of adverse events, whereas aromatase inhibitors (AIs) would not. Our findings provide evidence for the efficacy and safety of concurrent neoadjuvant endocrine therapy (AIs) with chemotherapy as an available option to achieve a higher clinical response rate for HR+HER2- breast cancer patients compared with chemotherapy alone with low toxicity. Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42022340725.

Cyclin-Dependent Kinase 4/6 Inhibitors as Neoadjuvant Therapy of Hormone Receptor-Positive/HER2-Negative Early Breast Cancer: What do we Know so Far?

The introduction of cyclin-dependent kinase 4/6 (CDK4/6) inhibitors to the treatment of hormone receptor-positive and human epidermal growth factor receptor 2-negative (HR+/HER2-) metastatic breast cancer is regarded as one of the greatest achievements of the last decades in breast oncology. To date, palbociclib, abemaciclib and ribociclib are the 3 approved CDK4/6 inhibitors that combined with endocrine therapy are now considered as the standard first-line treatment of metastatic HR+/HER2- breast cancer. The great success of these drugs in the setting of metastatic disease and the need to combat the high risk of recurrence have paved the way for a number of clinical trials to explore the use of CDK4/6 inhibitors in the neoadjuvant treatment of early breast cancer. In this review, we summarize the main findings of clinical trials that examined the use of CDK4/6 inhibitors in combination with hormone therapy or chemotherapy as neoadjuvant treatment of hormone receptor-positive and HER2-negative breast cancer. Active clinical trials that investigate different treatment schemes are also briefly presented and current limitations and future goals are discussed.

Therapeutic evolution in HR+/HER2- breast cancer: from targeted therapy to endocrine therapy.

Breast cancer, a complex and varied disease, has four distinct subtypes based on estrogen receptor and human epidermal growth factor receptor 2 (HER2) levels, among which a significant subtype known as HR+/HER2-breast cancer that has spurred numerous research. The prevalence of breast cancer and breast cancer-related death are the most serious threats to women's health worldwide. Current progress in treatment strategies for HR+/HER2-breast cancer encompasses targeted therapy, endocrine therapy, genomic immunotherapy, and supplementing traditional methods like surgical resection and radiotherapy. This review article summarizes the current epidemiology of HR+/HER2-breast cancer, introduces the classification of HR+/HER2-breast cancer and the commonly used treatment methods. The mechanisms of action of various drugs, including targeted therapy drugs and endocrine hormone therapy drugs, and their potential synergistic effects are deeply discussed. In addition, clinical trials of these drugs that have been completed or are still in progress are included.

Who can benefit from postmastectomy radiotherapy among HR+/HER2- T1-2 N1M0 breast cancer patients? An explainable machine learning mortality prediction based approach.

Objective: The necessity of postmastectomy radiotherapy(PMRT) for patients with HR+/HER2 T1-2 N1M0 breast cancer remains controversial. We want to use explainable machine learning to learn the feature importance of the patients and identify the subgroup of the patients who may benefit from the PMRT. Additionally, develop tools to provide guidance to the doctors. Methods: In this study, we trained and validated 2 machine learning survival models: deep learning neural network and Cox proportional hazard model. The training dataset consisted of 35,347 patients with HR+/HER2- T1-2 N1M0 breast cancer who received mastectomies from the SEER database from 2013 to 2018. The performance of survival models were assessed using a concordance index (c-index).Then we did subgroup analysis to identify the subgroup who could benefit from PMRT. We also analyzed the global feature importance for the model and individual feature importance for individual survival prediction. Finally, we developed a Cloud-based recommendation system for PMRT to visualize the survival curve of each treatment plan and deployed it on the Internet. Results: A total of 35,347 patients were included in this study. We identified that radiotherapy improved the OS in patients with tumor size >14mm and age older than 54: 5-year OS rates of 91.9 versus 87.2% (radio vs. nonradio, P <0.001) and cohort with tumor size >14mm and grade worse than well-differentiated, 5-year OS rates of 90.8 versus 82.3% (radio vs. nonradio, P <0.001).The deep learning network performed more stably and accurately in predicting patients survival than the random survival forest and Cox proportional hazard model on the internal test dataset (C-index=0.776 vs 0.641) and in the external validation(C-index=0.769 vs 0.650).Besides, the deep learning model identified several key factors that significantly influence patient survival, including tumor size, examined regional nodes, age at 45-49 years old and positive regional nodes (PRN). Conclusion: Patients with tumor size >14mm and age older than 54 and cohort with tumor size >14mm and grade worse than well-differentiated could benefit from the PMRT. The deep learning network performed more stably and accurately in predicting patients survival than Cox proportional hazard model on the internal test. Besides, tumor size, examined regional nodes, age at 45-49 years old and PRN are the most significant factors to the overall survival (OS).

Single-agent metronomic versus weekly oral vinorelbine as first-line chemotherapy in patients with HR-positive/HER2-negative advanced breast cancer: The randomized Tempo Breast study.

INTRODUCTION: Single-agent oral vinorelbine is a standard of care for hormone receptor (HR)-positive/human epidermal growth factor receptor 2 (HER2)-negative advanced breast cancer (ABC) that has progressed on endocrine therapy. Metronomic administration may offer a better balance of efficacy and safety than standard regimens, but data from previous trials are scarce. METHODS: In this open-label, multicenter, phase II trial, patients were randomized to oral vinorelbine administered on a metronomic (50 mg three times weekly) or weekly (60 mg/m2 in cycle 1, increasing to 80 mg/m2 if well tolerated) schedule. Treatment was continued until disease progression or intolerance. The primary endpoint was disease control rate (DCR, the proportion of patients with a best overall confirmed response of CR, PR, or stable disease lasting 6 months or more). RESULTS: One-hundred sixty-three patients were randomized and treated. The DCR was 63.4% (95% confidence interval [CI]: 52.0-73.8) with metronomic vinorelbine and 72.8% (95% CI: 61.8-82.1) with weekly vinorelbine. Weekly vinorelbine was also associated with longer progression-free survival (5.6 vs 4.0 months) and overall survival (26.7 vs 22.3 months) than metronomic vinorelbine, but was associated with more adverse events. CONCLUSIONS: In this randomized phase II trial, single-agent metronomic oral vinorelbine was effective and well tolerated as first-line chemotherapy for patients with HR-positive/HER2-negative ABC. Formal comparisons are not done in this phase II study and one can simply observe that confidence intervals of all endpoints overlap. When deciding for a chemotherapy after failure of endocrine therapy and CDK 4/6 inhibitors, oral vinorelbine might be an option to be given with either schedule. CLINICAL TRIAL REGISTRATION NUMBER: EudraCT 2014-003860-19.

Real-world comparative effectiveness of palbociclib plus aromatase inhibitor in HR+/HER2- metastatic breast cancer.

Aim: Provide real-world data on palbociclib as evidence of effectiveness in patient populations from routine clinical practice. Methods: This was a retrospective, observational cohort study of patients with HR+/HER2- metastatic breast cancer treated with palbociclib plus aromatase inhibitor (AI) or AI alone as first-line therapy within the US Oncology Network. Results: Patients treated with palbociclib plus AI (n = 838) versus AI alone (n = 450) had a numerically longer median overall survival (42.1 vs 35.7 months; hazard ratio [HR] = 0.90 [95% CI: 0.75-1.07]; p = 0.117) and a significantly extended real-world progression-free survival (21.0 vs 15.7 months; HR = 0.75 [95% CI: 0.64-0.88]; p = 0.0002) after normalized inverse probability treatment weighting. Conclusion: These real-world results support the use of palbociclib plus AI as first-line treatment in routine clinical practice for patients with HR+/HER2- metastatic breast cancer.

What is this summary about? This summary describes how well palbociclib works when used with an aromatase inhibitor in the real-world setting for people with a certain type of breast cancer that has spread to other areas of the body. Palbociclib stops cancer cells from growing and dividing. An aromatase inhibitor prevents the body from making the hormone estrogen, which is needed for certain types of breast cancer cells to grow. Palbociclib with an aromatase inhibitor is a standard first treatment used for people with this type of breast cancer that needs estrogen to grow and has spread to other areas of the body. In clinics, doctors may not always prescribe the two treatments together. The study wanted to find out if using the two treatments together worked better than using an aromatase inhibitor alone in the real-world setting. What were the results? The results suggest that in this population of patients treated in a real-world setting, people with breast cancer that needs estrogen to grow and has spread to other areas of the body who were treated with palbociclib plus an aromatase inhibitor lived longer without their cancer getting worse than those treated with an aromatase inhibitor alone. What do the results of the study mean? The results support the use of palbociclib with an aromatase inhibitor as a first treatment for breast cancer that has spread to other areas of the body, rather than an aromatase inhibitor only.

The adverse events of CDK4/6 inhibitors for HR+/ HER2- breast cancer: an umbrella review of meta-analyses of randomized controlled trials.

Background: The clinical selection of three CDK4/6 inhibitors presents a challenging issue, owing to the absence of distinct clinical case characteristics, biomarkers, and their comparable clinical benefits in progression-free survival and overall survival To inform clinical treatment decisions, we conducted a comprehensive evaluation of the adverse events associated with CDK4/6 inhibitors in combination with endocrine therapy for hazard ratio+/HER2-breast cancer. Methods: We searched Cochrane, PubMed, Embase, and Web of Science databases from their inception until 1 August 2022. The results were summarized narratively, and we assessed the methodological quality, reporting quality, and evidence quality of AEs by AMSTAR-2, PRISMA, and GRADE. Results: Our analysis included 24 meta-analyses systematic reviews that evaluated the quality of AEs in 13 cases of early breast cancer (EBC) and 158 cases of advanced breast cancer The addition of CDK4/6 inhibitors was found to significantly increase AEs of any grade and AEs of grade 3 or higher in early breast cancer, along with a significant increase in the risk of treatment discontinuation. In advanced breast cancer, high and moderate-quality evidence indicated that CDK4/6 inhibitors significantly increased AEs across all grades, including grade 3/4 AEs, leucopenia, grade 3/4 leucopenia, neutropenia, grade 3/4 neutropenia, anemia, grade 3/4 anemia, nausea, grade 3/4 constipation, fatigue, pyrexia, venous thromboembolism abdominal pain, and cough. However, they did not significantly elevate the incidence of grade 3/4 diarrhea. Subgroup analysis revealed that palbociclib primarily increased hematologic toxicity, particularly grade 3/4 neutropenia, anemia, and thrombocytopenia. Ribociclib was mainly associated with grade 3/4 neutropenia, prolonged QT interval, and alopecia. Abemaciclib was closely linked with diarrhea and elevated blood creatinine levels. Conclusion: The AEs associated with CDK4/6 inhibitors vary, necessitating individualized and precise clinical selection for optimal management. This approach should be based on the patient's medical history and the distinct characteristics of different CDK4/6 inhibitors to improve the patient's quality of life. Systematic Review Registration: [https://systematicreview.gov/], identifier [CRD42022350167].