Intermittent versus continuous first-line treatment for HER2-negative metastatic breast cancer: the Stop & Go study of the Dutch Breast Cancer Research Group (BOOG)

Racial and Ethnic Disparities in European Breast Cancer Clinical Trials

Breast cancer is the most prevalent female cancer worldwide with known correlations between the race and tumor characteristics of the patients and prognosis. International and US-based studies, however, have reported a disproportionate representation of Black and Hispanic patients in clinical trials. This is the first study assessing race and ethnicity reporting trends and inclusion in European breast cancer trials. The PubMed and ClinicalTrials.gov databases were systematically searched for trials on breast cancer treatment conducted exclusively in Europe between 2010 and 2022. Of the 97 identified trials, race was reported in 10.31%. Multinational participation, but not the study size or trial phase, was significantly associated with higher race reporting trends. These 10 trials featured a White-predominant population, with 1.08% Asian and 0.88% Black patients included. The acquisition of the race and ethnicity data of patients in European trials is lower compared to the U.S. or worldwide studies and does not permit extensive analysis of minority participation. In a limited analysis, the low rates of minority participation are concerning, based on population-based data on minorities in select European countries. These observations should encourage race reporting practices in European breast cancer trials and adequate minority participation to support the generalizability of the results of the studies and promote healthcare equity.

Front-Line Bevacizumab plus Chemotherapy with or without Maintenance Therapy for Metastatic Breast Cancer: An Observational Study by the Hellenic Oncology Research Group

Front-line bevacizumab (BEV) in combination with taxanes offers benefit in progression-free survival (PFS) in metastatic breast cancer (mBC). The medical records of mBC patients, treated with front-line BEV-based chemotherapy, were retrospectively reviewed in order to generate real life safety and efficacy data. Patients with human epidermal growth factor receptor 2 (HER2)-negative mBC treated with front-line BEV in combination with chemotherapy were eligible. Maintenance therapy with BEV and/or hormonal agents was at the physicians’ discretion. Among the 387 included patients, the most common adverse events were anemia (61.9%, mainly grade 1), grade 3/4 neutropenia (16.5%), grade 1/2 fatigue (22.3%), and grade 1/2 neuropathy (19.6%). Dose reductions were required in 164 cycles (7.1%) and toxicity led to treatment discontinuation in 21 patients (5.4%). The median PFS and the median overall survival (OS) were 13.3 (95% CI: 11.7–14.8) and 32.3 months (95% CI: 27.7–36.9), respectively. Maintenance therapy, with hormonal agents (ET) and/or BEV, was associated with longer OS versus no maintenance therapy (47.2 versus 23.6 months; p < 0.001) in patients with hormone receptor (HR)-positive disease and BEV maintenance offered longer OS versus no maintenance in patients with HR-negative disease (52.8 versus 23.3; p = 0.023). These real-life data show that front-line BEV-based chemotherapy in HER2-negative mBC patients is an effective treatment with an acceptable toxicity profile. The potential benefit of maintenance treatment, especially ET, is important and warrants further research.

Misleading Reporting (Spin) in Noninferiority Randomized Clinical Trials in Oncology With Statistically Not Significant Results: A Systematic Review

IMPORTANCE

Spin, the inaccurate reporting of randomized clinical trials (RCTs) with results that are not statistically significant for the primary end point, distorts interpretation of results and leads to misinterpretation. However, the prevalence of spin and related factors in noninferiority cancer RCTs remains unclear.

OBJECTIVE

To examine misleading reporting, or spin, and the associated factors in noninferiority cancer RCTs through a systematic review.

DATA SOURCES

A systematic search of the PubMed database was performed for articles published between January 1, 2010, and December 31, 2019, using the Cochrane Highly Sensitive Search Strategy.

STUDY SELECTION

Two investigators independently selected studies using the inclusion criteria of noninferiority parallel-group RCTs aiming to confirm effects to cancer treatments published between January 1, 2010, and December 31, 2019, reporting results that were not statistically significant for the primary end points.

DATA EXTRACTION AND SYNTHESIS

Standardized data abstraction was used to extract information concerning the trial characteristics and spin based on a prespecified definition. The main investigator extracted the trial characteristics while both readers independently evaluated the spin. The Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline was followed.

MAIN OUTCOMES AND MEASURES

The main outcome was spin prevalence in any section of the report. Spin was defined as use of specific reporting strategies, from whatever motive, to highlight that the experimental treatment is beneficial, despite no statistically significant difference for the primary outcome, or to distract the reader from results that are not statistically significant. The associations (prevalence difference and odds ratios [ORs]) between spin and trial characteristics were also evaluated.

RESULTS

The analysis included 52 of 2752 reports identified in the PubMed search. Spin was identified in 39 reports (75.0%; 95% CI, 61.6%-84.9%), including the abstract (34 reports [65.4%; 95% CI, 51.1%-76.9%]) and the main text (38 reports [73.1%; 95% CI, 59.7%-83.3%]). Univariate analysis found that the spin prevalence was higher in reports with data managers (prevalence difference, 27%; 95% CI, 1.1%-50.3%), reports without funding from for-profit sources (prevalence difference, 31.2%; 95% CI, 4.8%-53.8%), and reports of novel experimental treatments (prevalence difference, 37.5%; 95% CI, 5.8%-64.7%). Multivariable analysis found that novel experimental treatment (OR, 4.64; 95% CI, 0.98-22.02) and funding only from nonprofit sources only (OR, 5.20; 95% CI, 1.21-22.29) were associated with spin.

CONCLUSIONS AND RELEVANCE

In this systematic review, most noninferiority RCTs reporting results that were not statistically significant for the primary end points showed distorted interpretation and inaccurate reporting. The novelty of an experimental treatment and funding only from nonprofit sources were associated with spin.

Capecitabine in Combination with Endocrine Therapy as Maintenance Therapy after Bevacizumab Plus Paclitaxel Induction Therapy for Hormone Receptor-Positive, HER2-Negative Metastatic Breast Cancer: KBCSG-TR1214

Simple Summary

To investigate a possible treatment strategy for hormone receptor (HR)-positive, HER2-negative advanced and/or metastatic breast cancer (AMBC), we investigated the clinical usefulness of adding capecitabine to maintenance endocrine therapy after induction chemotherapy and the efficacy of reinduction chemotherapy. Patients who had received bevacizumab–paclitaxel induction therapy and did not have progressive disease were randomized to receive maintenance therapy with endocrine therapy alone (group E; n = 46) or endocrine therapy plus capecitabine (group EC; n = 44). The median progression-free survival (PFS) under maintenance therapy (primary endpoint) was significantly longer in group EC than in group E (11.1 vs. 4.3 months; hazard ratio, 0.53; p < 0.01). At 24 months from the induction therapy start, the overall survival (OS) rate was significantly higher in group EC than in group E (83.5% vs. 62.3%; p = 0.02). Therefore, the addition of capecitabine to maintenance endocrine therapy may be a beneficial option after induction chemotherapy for HR-positive, HER2-negative AMBC patients.

Abstract

Optimal treatment strategies for hormone receptor (HR)-positive, HER2-negative advanced and/or metastatic breast cancer (AMBC) remain uncertain. We investigated the clinical usefulness of adding capecitabine to maintenance endocrine therapy after induction chemotherapy and the efficacy of reinduction chemotherapy. Patients who had received bevacizumab–paclitaxel induction therapy and did not have progressive disease (PD) were randomized to maintenance therapy with endocrine therapy alone (group E) or endocrine plus capecitabine (1657 mg/m²/day on days 1–21, q4w) (group EC). In case of PD after maintenance therapy, patients received bevacizumab–paclitaxel reinduction therapy. Ninety patients were randomized. The median progression-free survival (PFS) under maintenance therapy (primary endpoint) was significantly longer in group EC (11.1 {95% CI, 8.0–11.8} months) than in group E (4.3 {3.6–6.0} months) (hazard ratio, 0.53; p < 0.01). At 24 months from the induction therapy start, the overall survival (OS) was significantly longer in group EC than in group E (hazard ratio, 0.41; p = 0.046). No difference was found in the time to failure of strategy (13.9 and 16.6 months in groups E and EC, respectively). Increased capecitabine-associated toxicities in group EC were tolerable. Addition of capecitabine to maintenance endocrine therapy may be a beneficial option after induction chemotherapy for HR-positive, HER2-negative AMBC patients.

Impressive long-term response with chemo-endocrine therapy in a premenopausal patient with metastatic breast cancer: A case report

RATIONALE

Patients with, or who develop, metastatic breast cancer have a 5-year relative survival of about 25%. Endocrine therapy clearly improves outcomes in patients with estrogen receptor-positive breast cancer. In the metastatic setting, the primary goal of treatment is to maintain long-term disease control with good quality of life. Rarely, exceptional responders achieve durable disease control, and potential cures cannot be ruled out.

PATIENT CONCERNS

We report the case of a 39-year-old woman with primary breast cancer and associated synchronous bone metastases, who experienced a disease response of 12 years with hormonal therapy as maintenance after first line chemotherapy, with a good toxicity profile.

DIAGNOSIS

The patient was diagnosed with estrogen receptor + human epidermal growth factor receptor 2 (HER2)- metastatic breast cancer with synchronous bone metastases.

INTERVENTIONS

This patient was treated with chemotherapy for 6 cycles as a first-line therapy following by endocrine treatment given as a maintenance therapy.

OUTCOMES

Our patient experienced a progression-free survival >12 years with an exceptionally good quality of life.

LESSONS

Our anecdotal experience highlights the existence of exceptional responders among patients with hormone receptor-positive metastatic breast cancer, who achieve clinical remission and durable disease control with endocrine therapy. Being able to identify these patients could help in the selection of the best treatment option among the many available.

Secondary analyses of the randomized phase III Stop&Go study: efficacy of second-line intermittent versus continuous chemotherapy in HER2-negative advanced breast cancer

Background: Previously, we showed that reintroduction of the same (first-line) chemotherapy at progression could only partially make up for the loss in efficacy as compared to continuously delivered first-line chemotherapy. Here, we report the probability of starting second-line study chemotherapy in the Stop&Go trial, and the progression-free survival (PFS) and overall survival (OS) of patients who received both the first- and second-line treatment in an intermittent versus continuous schedule.Methods: First-line chemotherapy comprised paclitaxel plus bevacizumab, second-line capecitabine or non-pegylated liposomal doxorubicin, given per treatment line as two times four cycles (intermittent) or as eight consecutive cycles (continuous).Results: Of the 420 patients who started first-line treatment within the Stop&Go trial (210:210), a total of 270 patients continued on second-line study treatment (64% of all), which consisted of capecitabine in 201 patients and of non-pegylated liposomal doxorubicin in 69 patients, evenly distributed between the treatment arms. Median PFS was 3.7 versus 5.0 months (HR 1.07; 95% CI: 0.82-1.38) and median OS 10.9 versus 12.4 months (HR 1.27; 95% CI: 0.98-1.66) for intermittent versus continuous second-line chemotherapy. Second-line PFS was positively influenced by prior hormonal therapy for metastatic disease and longer first-line PFS duration, while triple-negative tumor status had a negative influence. Patients with a shorter time to progression (TTP) in first-line (≤10 months) had a higher probability of starting second-line treatment if they received intermittent compared to continuous chemotherapy (OR 1.97; 95% CI: 1.02-3.80).Conclusion: We recommend continuous scheduling of both the first- and second-line chemotherapy for advanced breast cancer.

The role of chemotherapy in treatment of advanced breast cancer: an overview for clinical practice

This review aims to evaluate the role of chemotherapy-containing regimens in the treatment of advanced breast cancer (ABC), with the purpose to optimize selection, sequencing and duration of treatment with the currently available agents for clinical practice. Data from observational as well as randomized phase II and III studies were included. Chemotherapy yielded a median overall survival (OS) of 2 years in registration studies, with comparable efficacy of different agents. Combining chemotherapy agents did not yield OS improvement and caused greater toxicity compared with single-agent chemotherapy. Continuing chemotherapy till progression or unacceptable toxicity generated greater efficacy without detrimental impact on quality of life compared with a limited amount of cycles. In real-world studies, benefits after third-line chemotherapy were modest compared with first- and second-line. Furthermore, effects of previous chemotherapy predicted effects of next-line therapy in real-world. Physicians increasingly prescribed capecitabine or taxanes as first- or second-line chemotherapy over time.

Breast Cancer, Version 3.2020, NCCN Clinical Practice Guidelines in Oncology

Several new systemic therapy options have become available for patients with metastatic breast cancer, which have led to improvements in survival. In addition to patient and clinical factors, the treatment selection primarily depends on the tumor biology (hormone-receptor status and HER2-status). The NCCN Guidelines specific to the workup and treatment of patients with recurrent/stage IV breast cancer are discussed in this article.

The influence on quality of life of intermittent scheduling in first- and second-line chemotherapy of patients with HER2-negative advanced breast cancer

BACKGROUND

The Stop&Go study randomized patients with advanced breast cancer to intermittent (two times four) or continuous (eight subsequent cycles) first- and second-line chemotherapy.

METHODS

QoL was measured with RAND-36 questionnaires every 12 weeks. The primary objective was to estimate differences in changes from baseline between intermittent and continuous treatment. An effect size of 0.5 SD (5 points) was considered clinically meaningful.

RESULTS

A total of 398 patients were included with a median follow-up of 11.4 months (IQR 5.6-22.2). Mean physical QoL baseline scores were 38.0 resp. 38.2, and mental scores 45.0 resp. 42.4 for intermittent and continuous treatment. Physical QoL declined linearly in the intermittent arm causing a clinically meaningful difference of 5.40 points at 24 months (p < 0.001), while scores in the continuous arm stabilized after a small decline of ± 3.4 points at 12 months. Conversely, mental QoL was fairly stable and even improved with 1.58 (p = 0.005) and 2.48 points (p < 0.001) at 12 months for intermittent and continuous treatment, respectively. When comparing arms for both components in changes from baseline, the maximum differences were 2.46 (p = 0.101) and 1.95 points (p = 0.182) for physical and mental scores, both measured at 30 months and in favor of continuous treatment.

CONCLUSION

Intermittent first- and second-line chemotherapy in patients with HER2-negative advanced breast cancer showed a trend for worse impact on QoL compared to continuous chemotherapy, with neither significant nor meaningful differences in course. We recommend prescribing chemotherapy continuously until progressive disease or unacceptable toxicity. Trial registration EudraCT 2010-021519-18; BOOG 2010-02.

Mitochondrial fission regulator 2 (MTFR2) promotes growth, migration, invasion and tumour progression in breast cancer cells

Introduction: Mitochondrial fission regulator 2 (MTFR2) belongs to the MTFR family, and 2 isoforms of MTFR2 are produced by alternative splicing. The role of MTFR2 in breast cancer (BC) remains unknown.

Results: MTFR2 was upregulated in BC tissues and was strongly associated with tumor characteristics. Moreover, Kaplan-Meier and Cox proportional hazards analyses indicated that high MTFR2 expression was related to poor overall survival. In addition, the capacity for migration and invasion decreased in two BC cell lines after knockdown of MTFR2. The epithelial-mesenchymal transition pathway was inhibited in MTFR2-silenced cells. MTFR2 can switch glucose metabolism from OXPHS to glycolysis in a HIF1α- and HIF2α-dependent manner.

Conclusion: Taken together, our results indicate that increased expression of MTFR2 is associated with tumour progression in breast cancer cells through switching glucose metabolism from OXPHS to glycolysis in a HIF1α- and HIF2α-dependent manner.

Materials and methods: We obtained data from The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO) to analyse MTFR2 expression in BC. The prognostic value of MTFR2 expression was assessed using the Kaplan-Meier method. The biological influence of MTFR2 on BC cell lines was studied using proliferation, Transwell migration, invasion and mitochondrial function assays.

Maintenance Therapy in HER2-Negative Metastatic Breast Cancer: A New Approach for an Old Concept

The aim of this article is to discuss the role of maintenance therapy with chemotherapy, endocrine therapy, or bevacizumab-based combination therapy in patients with human epidermal growth factor receptor 2 (HER2)-negative metastatic breast cancer. The optimization of maintenance therapy in patients with HER2-negative metastatic breast cancer must be based on disease profile (tumor subtype and endocrine-sensitive status), the prior use of bevacizumab-containing regimens, and the number of prognostic risk factors. Chemotherapy should be used in patients with triple-negative breast cancer and endocrine-resistant hormone receptor-positive metastatic breast cancer, whereas endocrine therapy is the preferred option for patients with endocrine-sensitive hormone receptor-positive metastatic breast cancer. After first-line bevacizumab plus chemotherapy, bevacizumab may be continued until disease progression or unacceptable toxicity, and endocrine therapy or capecitabine may be added. The goals of maintenance therapy in patients with HER2-negative metastatic breast cancer are to improve and maintain clinical response, increase time to progression, extend overall survival, relieve tumor-related symptoms, and delay the use of aggressive therapies, without compromising quality of life. Maintenance therapy, using chemotherapy, endocrine therapy, and combined therapy with bevacizumab, is a reasonable strategy to achieve these goals in patients with either triple-negative breast cancer or hormone receptor-positive and HER2-negative metastatic breast cancer. Ongoing clinical studies of new molecular-targeted therapies may provide additional pharmacological options for future maintenance strategies in these patients.