Clinical pattern of primary systemic therapy and outcomes of estrogen receptor-positive, HER2-negative metastatic breast cancer: a review of a single institution

Shorter duration of first-line chemotherapy reflects poorer outcomes in patients with HER2-negative advanced breast cancer: a multicenter retrospective study

Post-progression survival affects overall survival (OS) in patients with HER2-negative advanced breast cancer (HER2-ABC); thus, the optimal choice of first-line chemotherapy (1LCT) remains controversial. We investigated patients with HER2-ABC focusing on their sensitivity to 1LCT. We retrospectively analyzed patients with HER2-ABC who received 1LCT between January 2011 and December 2016 in three participating institutions. We identified 149 patients in the shorter and 152 patients in the longer time to treatment failure (TTF) groups. The median OS was significantly longer in the longer TTF group (hazard ratio [HR] 0.44, P < 0.001, log-rank). In the shorter TTF group, OS of patients who received paclitaxel plus bevacizumab (PB) therapy was significantly inferior to that of those who received chemotherapy other than PB (HR 2.57, P < 0.001, log-rank), and subsequent eribulin therapy significantly improved OS from 1LCT initiation (Wilcoxon P < 0.001); multivariate analyses showed that 1LCT PB therapy was an independent risk factor for poorer OS (HR 2.05, P = 0.003), while subsequent eribulin therapy was an independent prognostic factor for better OS (HR 0.56, P = 0.004). OS was significantly poorer in patients with HER2-ABC with a shorter duration of 1LCT, including PB therapy, while subsequent eribulin therapy improved OS.

The Place of Chemotherapy in The Evolving Treatment Landscape for Patients With HR-positive/HER2-negative MBC

Endocrine therapy (ET) for the treatment of patients with hormone receptor-positive/human epidermal growth factor receptor 2-negative (HR-positive/HER2-negative) metastatic breast cancer (MBC) has changed markedly over recent years with the emergence of new ETs and the use of molecularly targeted agents. Cytotoxic chemotherapy continues, however, to have an important role in these patients and it is important to maximize its efficacy while minimizing toxicity to optimize outcomes. This review examines current HR-positive/HER2-negative MBC clinical guidelines and addresses key questions around the use of chemotherapy in the face of emerging therapeutic options. Specifically, the indications for chemotherapy in patients with HR-positive/HER2-negative MBC and the choice of optimal chemotherapy are discussed.

Progression-free survival on endocrine therapy, before or after chemotherapy, in hormone receptor-positive HER2-negative metastatic breast cancer

PURPOSE

A major question when treating HR+/HER2- metastatic breast cancer (MBC) is whether early introduction of chemotherapy (CT) increases endocrine resistance. We aimed to describe progression-free survival (PFS) under first endocrine therapy (ET) depending on whether given before or after CT in a large nationwide cohort, in the pre-CDK era.

METHODS

The real-life retrospective ESME database includes all patients with MBC whose first-line treatment was initiated between 2008 and 2014 in one of the 18 French Comprehensive Cancer Centres. Our primary objective was to compare PFS from start of first ET in patients with HR+/HER2- MBC who received ET or CT first.

RESULTS

We identified 6293 patients who received at least one ET line during their first two therapeutic lines for MBC. As first-line therapy, 3832 (60.9%) received ET alone (ET1 1st group), whilst 2461 (39.1%) received CT, including 2024 patients (32.2%) with maintenance ET after CT (ET1 after CT group). Median PFS under first ET was 12.4 months (95% CI 11.9-13.1) in ET 1st group vs. 12.6 months in ET1 after CT group (95% CI 12.1-13.4), HR 0.96 (95% CI 0.90-1.01, P = 0.1277).

CONCLUSIONS

PFS under first ET appears identical whether prescribed before or after chemotherapy. These data suggest chemotherapy does not promote endocrine resistance.

Real-World Efficacy of Fulvestrant Monotherapy as the First Treatment or Maintenance Treatment in Patients with Metastatic Breast Cancer

Background

Fulvestrant 500 mg monotherapy is recommended as the first-line endocrine treatment in postmenopausal women with hormone receptor-positive metastatic breast cancer (MBC). It is also used in MBC maintenance treatment. However, few studies have compared the efficacy of fulvestrant during the initial treatment with that during maintenance treatment.

Patients and Methods

MBC patients who were treated with fulvestrant either as initial therapy for metastatic disease or after progression following one line of chemotherapy between January 2016 and December 2017 were identified from the database of the Affiliated Hospital of Qingdao University. The primary end point was progression-free survival (PFS).

Results

The study included 135 MBC patients who were treated with fulvestrant; 116 patients who received fulvestrant as first-line treatment were divided into 2 groups: the no-chemotherapy treatment (NCT) group received fulvestrant as initial therapy during disease progression, and the chemotherapy treatment (CT) group received fulvestrant as maintenance following disease stabilization or response to previous chemotherapy. The median PFS was 16 months in NCT patients and 8 months in the CT group. Patients who had a longer disease-free survival, no visceral metastasis and one metastasis site, benefited from fulvestrant as first-line treatment during disease progression. Patients with 2 or more metastasis sites benefited from chemotherapy as first-line treatment and fulvestrant as maintenance treatment.

Conclusions

Fulvestrant monotherapy showed good clinical activity and safety in patients with MBC who were treated upon disease progression and in those receiving maintenance therapy.

Treatment and Monitoring Variability in US Metastatic Breast Cancer Care

PURPOSE

Treatment and monitoring options for patients with metastatic breast cancer (MBC) are increasing, but little is known about variability in care. We sought to improve understanding of MBC care and its correlates by analyzing real-world claims data using a search engine with a novel query language to enable temporal electronic phenotyping.

METHODS

Using the Advanced Cohort Engine, we identified 6,180 women who met criteria for having estrogen receptor-positive, human epidermal growth factor receptor 2-negative MBC from IBM MarketScan US insurance claims (2007-2014). We characterized treatment, monitoring, and hospice usage, along with clinical and nonclinical factors affecting care.

RESULTS

We observed wide variability in treatment modality and monitoring across patients and geography. Most women received first-recorded therapy with endocrine (67%) versus chemotherapy, underwent more computed tomography (CT) (76%) than positron emission tomography-CT, and were monitored using tumor markers (58%). Nearly half (46%) met criteria for aggressive disease, which were associated with receiving chemotherapy first, monitoring primarily with CT, and more frequent imaging. Older age was associated with endocrine therapy first, less frequent imaging, and less use of tumor markers. After controlling for clinical factors, care strategies varied significantly by nonclinical factors (median regional income with first-recorded therapy and imaging type, geographic region with these and with imaging frequency and use of tumor markers; P < .0001).

CONCLUSION

Variability in US MBC care is explained by patient and disease factors and by nonclinical factors such as geographic region, suggesting that treatment decisions are influenced by local practice patterns and/or resources. A search engine designed to express complex electronic phenotypes from longitudinal patient records enables the identification of variability in patient care, helping to define disparities and areas for improvement.

Leptomeningeal Metastasis in ER + HER2- Advanced Breast Cancer Patients: A Review of the Cases in a Single Institute Over a 15-year Period

PURPOSE

While leptomeningeal metastasis (LM) from estrogen receptor-positive, HER2-negative advanced breast cancer (ER + HER2-ABC) has a poor prognosis, the details of ER + HER2-LM are unclear. We therefore retrospectively investigated patients with LM from ER + HER2-ABC.

METHODS

ER + HER2-ABC patients who received any therapy at Shizuoka Cancer Center between October 2002 and December 2017 were retrospectively analyzed. Patients with central nervous system (CNS) metastases were divided into three groups: brain metastasis (BM) only (B group); BM with LM (BL group); and LM only (L group).

RESULTS

Among 369 patients, 102 developed CNS metastases: 70 (68.6%), 13 (12.8%), and 19 (18.6%) in the B, BL, and L groups, respectively. The L group showed a later onset, poorer performance status, more symptoms, and more skull metastasis than the other groups. Radiotherapy as the initial treatment was introduced to 13/13 (100%) and 15/19 (78.9%) in the BL and L groups, respectively. Subsequent systemic therapy excluding best supportive care was introduced to 5/13 (38.5%) and 5/19 (26.3%) in the BL and L groups, respectively. The median overall survival from the diagnosis of CNS lesions was 295.0, 146.0, and 99.0 days in the B, BL, and L groups, respectively, and worsening of CNS lesions was the major cause of death in the BL and L groups. Multivariate analyses showed that concurrent soft tissue metastasis (hazard ratio, 4.620) and subsequent systemic therapy (hazard ratio, 0.063) were prognostic for the L group.

CONCLUSION

Management of LM from ER + HER2-ABC remains challenging, so a multimodal approach with novel systemic therapy is warranted.

New insights into patterns of first metastatic sites influencing survival of patients with hormone receptor-positive, HER2-negative breast cancer: a multicenter study of 271 patients

Background

The initial therapeutic strategy for hormone receptor-positive (HR+), HER2-negative (HER2-) breast cancer is based on the first metastatic site; however, little evidence is available regarding the influence of metastatic distribution patterns of first metastatic sites on prognosis. In this study, we aimed to identify the metastatic distribution patterns of first metastatic sites that significantly correlate with survival after recurrence.

Methods

We performed a retrospective review of records from 271 patients with recurrent metastatic HR+/HER2- breast cancer diagnosed between January 2000 and December 2015. We assessed survival after recurrence according to the metastatic distribution patterns of the first metastatic sites and identified significant prognostic factors among patients with single and multiple metastases.

Results

Prognosis was significantly better in patients with a single metastasis than in those with multiple metastases (median overall survival after recurrence: 5.86 years vs. 2.50 years, respectively, p < 0.001). No metastatic organ site with single metastasis was significantly associated with prognostic outcome, although single metastasis with diffuse lesions was an independent risk factor for worse prognosis (HR: 3.641; 95% CI: 1.856–7.141) and more easily progressing to multiple metastases (p = 0.002). Multiple metastases, including liver metastasis (HR: 3.145; 95% CI: 1.802–5.495) or brain metastasis (HR: 3.289; 95% CI: 1.355–7.937), were regarded as significant independent poor prognostic factors; however, multiple metastases not involving liver or brain metastasis were not significantly related to prognosis after recurrence.

Conclusions

Single metastases with diffuse lesions could more easily disseminate systemically and progress to multiple metastases, leading to a poor prognosis similar to multiple metastases. Our findings indicate that the reconsideration of the determinant factors of therapeutic strategies for first recurrence in HR+/HER2- breast cancer may be needed.

Real-world Data on First-line Systemic Therapy for Hormone Receptor-positive HER2-negative Metastatic Breast Cancer: A Trend Shift in the Era of CDK 4/6 Inhibitors

Hormone receptor-positive (HR⁺) human epidermal growth factor receptor-2 negative (HER2^-) tumors represent the most common subtype of metastatic breast cancer (MBC). International guidelines clearly state that endocrine therapy (ET) should be considered the preferred first-line therapy for these patients in the absence of very symptomatic visceral disease or evidence of endocrine resistance. Nonetheless compliance with guidelines significantly vary worldwide for many different reasons. Historically, a substantial proportion of patients with HR⁺ HER2^- MBC have been treated with chemotherapy (CT) in first-line setting, jeopardizing patients' quality of life without a significant benefit in outcome. In 17 observational studies, including more than 63,000 patients, ET was most frequently used in first-line treatment of HR⁺/HER2^- MBC (range, 42%-87%), nonetheless a high proportion of patients received CT (13%-66%) as initial therapy. More recently, results of clinical trials with CDK 4/6 inhibitors improved response, progression-free and overall survival in this population and are currently the standard of care. There was a trend toward increased use of ET in recent years. This review article aims to evaluate real-world data on patterns of first-line treatment of HR⁺ HER2^- MBC with a special focus on the use of CT in this setting and the potential implications and perceived preliminary changes after the introduction of CDK 4/6 inhibitors.

Endocrine Therapy for Hormone Receptor-Positive Advanced Breast Cancer: A Nation-Wide Multicenter Epidemiological Study in China

Background

Clinical guidelines generally recommend endocrine therapy (ET) as first-line treatment of hormone receptor-positive advanced breast cancer (HR+ ABC) whereas chemotherapy (CT) should be considered in the presence of life-threatening disease or limited clinical benefit after three sequential ET regimens. However, it is unclear if real-world clinical practice is in accordance with the current guidelines. This study was to present the real-world treatment patterns and ET regimens among HR+ ABC patients in China.

Methods

Using data from the Nation-wide Multicenter Retrospective Clinical Epidemiology Study of Female Advanced Breast Cancer in China (ClinicalTrials.gov identifier: NCT03047889), we investigated the clinicopathological characteristics, clinical profiles, and treatment patterns of HR+ ABC patients from January 2012 to December 2014.

Results

A total of 2,342 patients with HR+ ABC were included in this study. Our findings revealed that, in comparisons with those receiving initial CT (n = 1445), patients initiated ET (n =402) were significantly older, later recurrent after adjuvant treatment, with a lower rate of visceral involvement and a decreasing quantity of metastatic sites. A total of 1,308 patients received palliative ET while only 18.9% patients (n = 247) reached three lines of ET. Among patients completing more than one line of ET, the median treatment duration was 8 months for the first line, 6 months for the second line, and 3 months for the third line for patients receiving ET. In the advanced setting, the choices of palliative ET regimens were diverse, yet aromatase inhibitor (AI) monotherapy was still the overall mainstay of ET; in contrast, patients were less accessible to everolimus plus AI regimen in this population.

Conclusions

Less than one quarter of patients initiated palliative ET for HR+ ABC in routine clinical practice. Patients who received multi-lines of ET experienced successive shorter durations following each line of therapy. This real-life data provides a solid overview of ET for HR+ ABC from China, indicating unmet need for treatment options that improve the effectiveness of endocrine therapy.

Efficacy of Circulating Tumor Cell Count-Driven vs Clinician-Driven First-line Therapy Choice in Hormone Receptor-Positive, ERBB2-Negative Metastatic Breast Cancer: The STIC CTC Randomized Clinical Trial

Importance

The choice between chemotherapy and endocrine therapy as first-line treatment for hormone receptor-positive, ERBB2 (also known as HER2)-negative metastatic breast cancer is usually based on the presence of clinical features associated with a poor prognosis. In this setting, a high circulating tumor cell (CTC) count (≥5 CTCs/7.5 mL) is a strong adverse prognostic factor for overall survival and progression-free survival (PFS).

Objective

To compare the efficacy of a clinician-driven treatment choice vs a CTC-driven choice for first-line treatment.

Interventions

In the CTC arm, patients received chemotherapy or endocrine therapy according to the CTC count (chemotherapy if ≥5 CTCs/7.5 mL; endocrine therapy if <5 CTCs/7.5 mL), whereas in the control arm, the choice was left to the investigator.

Design, Setting, and Participants

In the STIC CTC randomized, open-label, noninferiority phase 3 trial, participants were randomized to a clinician-driven choice of first-line treatment or a CTC count-driven first-line treatment choice. Eligible participants were premenopausal and postmenopausal women 18 years or older diagnosed with hormone receptor-positive, ERBB2-negative metastatic breast cancer. Data were collected at 17 French cancer centers from February 1, 2012, to July 28, 2016, and analyzed June 2019 to October 2019.

Main Outcome and Measures

The primary end point was the investigator-assessed PFS in the per-protocol population, with a noninferiority margin of 1.25 for the 90% CI of the hazard ratio.

Results

Among the 755 women in the per-protocol population, the median (range) age was 63 (30-88) years [64 (30-88) years for the 377 patients allocated to the CTC arm and 63 (31-87) years for the 378 patients allocated to the standard arm]; 138 (37%) and 103 (27%) received chemotherapy, respectively. Median PFS was 15.5 months (95% CI, 12.7-17.3) in the CTC arm and 13.9 months (95% CI, 12.2-16.3) in the standard arm. The primary end point was met, with a hazard ratio of 0.94 (90% CI, 0.81-1.09).

Conclusions and Relevance

This randomized clinical trial found that the CTC count may be a reliable biomarker method for guiding the choice between chemotherapy and endocrine therapy as the first-line treatment in hormone receptor-positive, ERBB2-negative metastatic breast cancer.

Trial Registration

ClinicalTrials.gov Identifier: NCT01710605.

Systemic treatment of hormone receptor positive, human epidermal growth factor 2 negative metastatic breast cancer: retrospective analysis from Leeds Cancer Centre

Background

Study aimed to characterise treatment and outcomes for patients with hormone receptor positive (HR+), human epidermal growth factor 2 negative (HER2-) metastatic breast cancer (MBC) within a large regional cancer centre, as a benchmark for evaluating real-world impact of novel therapies.

Methods

Retrospective longitudinal cohort, using electronic patient records of adult females with a first diagnosis of HR+/HER2- MBC January 2012–March 2018.

Results

One hundred ninety-six women were identified with HR+/HER2- MBC. Median age was 67 years, 85.2% were post-menopausal and median time between primary diagnosis and metastasis was 5.4 years. Most (75.1%) patients received endocrine therapy as first line systemic treatment (1st LoT); use of 1st LoT chemotherapy halved between 2012 and 2017. Patients receiving 1st LoT chemotherapy were younger and more likely to have visceral metastasis (p < 0.01). Median OS was 29.5 months and significantly greater for patients with exclusively non-visceral metastasis (p < 0.01). The adjusted hazard ratio for death of patients with visceral (or CNS) metastasis was 1.91 relative to those with exclusively non-visceral metastasis.

Conclusions

Diverse endocrine therapies predominate as 1st LoT for patients with HR+/HER2- MBC, chemotherapy being associated with more aggressive disease in younger patients, emphasising the importance of using effective and tolerable therapies early.

Downregulation of MMSET impairs breast cancer proliferation and metastasis through inhibiting Wnt/β-catenin signaling

Background

Recently, the biggest challenge in the treatment of breast cancer is the metastasis of breast cancer cells. Multiple myeloma SET protein (MMSET), a histone lysine methyltransferase, overexpressed in various human cancers, was reported to be associated with carcinogenesis of human cancers.

Methods

Expression of MMSET in breast cancer cell lines and tissues was quantified by real-time PCR and Western blotting. Immunohistochemistry was employed to analyze MMSET expression in 163 clinicopathologically characterized breast cancer cases. Cell functional assays such as MTT assay, colony formation, BrdU assay, flow cytometry, wound healing, Transwell assay, and 3D culture were used to investigate the effect of MMSET in the development and metastasis of human breast cancer. Effects of MMSET on Wnt/β-catenin signaling pathway were further studied by using Western blotting analysis.

Results

Our results showed that MMSET expression was markedly overexpressed in breast cancer cells and clinical specimens and was significantly correlated with patients’ clinicopatho-logic characteristics and prognosis. Moreover, silencing endogenous MMSET significantly inhibited the proliferation, migration, and metastasis of breast cancer cells through inhibiting the Wnt/β-catenin pathway.

Conclusion

This study found that the downregulated expression of MMSET impaired proliferation and metastasis of human breast cancer through inhibiting Wnt/β-catenin signaling pathway. Notably, our results indicated that MMSET could be a useful biomarker for the prognosis of breast cancer.

Treatment after Progression on Fulvestrant among Metastatic Breast Cancer Patients in Clinical Practice: a Multicenter, Retrospective Study

Fulvestrant (Ful) is an effective and widely used agent for first- and second-line treatment of hormone receptor-positive, human epidermal growth factor receptor-2-negative (HR+/HER2-) metastatic breast cancer (MBC). However, there is no evidence of treatment after progression on Ful. Our study aimed to investigate the profile of daily practice regarding therapy after Ful. A consecutive series of 131 HR+, HER2- MBC patients who failed Ful 500 mg as first-line or second-line therapy from June 2014 to June 2017 in 6 institutions were included and analysed. Among 131 patients who failed Ful with similar baseline characteristics, 31 (23.7%) received endocrine therapy (ET), and 100 (76.3%) were treated with chemotherapy (CT). The most frequently applied CT regimen was capecitabine (32%), and the ET regimen was exemestane + everolimus (35.5%). Multivariate analysis showed that patients with bone-only metastasis were associated with lower CT use (OR = 7.97, 95% CI 1.51-41.84, P = 0.01). Among patients who received CT and ET as subsequent treatments, the median progression-free survival (PFS) was 7.5 months (95% CI 6.2-8.8) and 6.0 months (95% CI 4.1-7.9), respectively (p = 0.03). Among patients who were resistant to Ful (PFS < 6 months), the PFS on CT was significantly longer than that on ET (7.1 months vs 3.9 months, p = 0.024, HR = 0.5, 95% CI 0.26-0.97); however, among patients with a PFS ≥6 months on Ful, the efficacy of CT and ET was similar. Additionally, among patients with an older age, bone-only metastasis and ≥3 metastatic sites, no significant difference was observed between the CT and ET groups. Moreover, ET was much more tolerated than CT in terms of the incidence of grade 3/4 toxicities (9.6% vs 27%, P < 0.05). Median overall survival (OS) was not reached. Thus, our findings reveal the pattern of post-Ful treatment in current clinical practice and provide evidence on the efficacy, safety and choice of these treatments.

The predictive ability of plasma ESR1 mutations for the efficacy of endocrine therapy in hormone-receptor-positive advanced breast cancer

Purpose

The predictive ability of plasma ESR1 mutations for outcomes among patients with advanced breast cancer undergoing endocrine therapy (ET) remains disputable. We performed a comprehensive meta-analysis of published studies to clarify the impact of plasma ESR1 mutations on clinical outcomes for patients after subsequent ET.

Materials and methods

An electronic search was performed to identify eligible studies. Studies analyzing progression-free survival (PFS) and/or overall survival (OS) according to plasma ESR1 mutation status after subsequent ET were included. HRs were calculated using a fixed- or random-effects model according to heterogeneity. Pooled HRs and 95% CIs were used to estimate the effects.

Results

Six studies including 705 patients with advanced breast cancer met the inclusion criteria. The impact of plasma ESR1 mutations on PFS and OS after subsequent ET was reported in six studies (seven groups) and two studies, respectively. Meta-analysis results showed that the pooled HR for ESR1 mutations was 1.70 (95% CI, 1.05-2.74; P=0.03) for OS, which was statistically significant for predicting poor survival, and 1.56 (95% CI, 1.13-2.14; P=0.006) for PFS; however, Begg's and Egger's test results identified the presence of bias. The trim-and-fill method was used, and after incorporation of the imputed studies, the HR was 1.16 (95% CI, 0.88-1.53, P=0.30) for PFS, which indicates that plasma ESR1 mutation had no effect on PFS after subsequent ET. Subgroup analysis suggested that plasma ESR1 mutations were correlated with shorter PFS (HR, 1.98; 95% CI, 1.12-3.51; P=0.02) in patients subsequently treated with aromatase inhibitors (AIs), whereas no association with PFS was observed for patients subsequently treated with non-AI ET (HR, 1.08; 95% CI, 0.85-1.38; P=0.54) or fulvestrant (HR, 1.03; 95% CI, 0.79-1.34; P=0.83).

Conclusion

The current meta-analysis demonstrates that plasma ESR1 mutation status is not a predictor of ET efficacy for all drugs without distinction in patients with hormone-receptor-positive advanced breast cancer. ESR1 mutation predicted a poor response to AIs, whereas it was not predictive of non-AI ET efficacy, especially for fulvestrant.