Treatment of metastatic breast cancer: second line and beyond

Fulvestrant with or without anti-HER2 therapy in patients in a postmenopausal hormonal state and with ER-positive HER2-positive advanced or metastatic breast cancer: A subgroup analysis of data from the Safari study (JBCRG-C06)

BACKGROUND

The role of endocrine therapy in the treatment of patients in a postmenopausal hormonal state and with estrogen receptor (ER)-positive, human epidermal growth factor receptor 2 (HER2)-positive advanced or metastatic breast cancer (AMBC) is unclear.

METHODS

We analyzed the data from 94 patients with ER-positive HER2-positive AMBC enrolled in the Safari study (UMIN000015168), a retrospective cohort study of 1072 ER-positive AMBC patients in a postmenopausal hormonal state who received fulvestrant 500 mg (F500): (1) to compare time to treatment failure (TTF) and overall survival (OS) by treatment group, and TTF by treatment line; (2) in patients who received endocrine therapy (including F500) or anti-HER2 therapy as initial systemic therapy before chemotherapy, to investigate relations between TTF for the first-line therapy or time to chemotherapy (TTC) and OS; (3) to investigate factors associated with OS.

RESULTS

The TTF was longer in the patients treated with F500 as first- or second-line therapy (n = 20) than in those who received later-line F500 therapy (n = 74) (6.6 vs. 3.7 months; HR, 1.98; p = 0.014). In the 59 patients who received endocrine therapy or anti-HER2 therapy as initial systemic therapy before chemotherapy, those with TTC ≥3 years had longer median OS than those with TTC <3 years (10.5 vs. 5.9 years; HR, 0.32; p = 0.001). Longer TTC was associated with prolonged OS.

CONCLUSIONS

In patients with ER-positive HER2-positive AMBC enrolled in the Safari study, TTF was longer in patients who received F500 as first- or second-line therapy. In patients who received chemotherapy-free initial systemic therapy, the prolonged OS in those with TTC ≥3 years suggests that this value may be a helpful cut-off for indicating clinical outcomes.

Is Palbociclib a cost-effective strategy in the second-line treatment of metastatic breast cancer in Iran?

BACKGROUND & AIMS

This study evaluates the cost-effectiveness of Palbociclib in the second-line treatment of hormone receptor-positive (HR+) human epidermal growth factor receptor 2-negative (HER2-) metastatic breast cancer (MBC) in Iran.

METHODS

The present economic evaluation used a partitioned survival model (PSM). This model compares lifetime costs and disease outcomes among groups receiving different medication combinations containing Palbociclib, Fulvestrant, Everolimus, Ribociclib, and Abemaciclib as the second-line therapy for HR+/HER2- MBC. The model was conducted from Iran's healthcare perspective, structured with 1-month cycles, and the evaluation time horizon in the base analysis was set to 180 cycles (15 years). Transition probabilities were extracted using the survival curves. The cost information was extracted based on the year 2020. The Quality Adjusted Life Years (QALY) was considered the final outcome unit, and the cost-effectiveness of different combinations is calculated as cost per QALY. The annual discount rate of 5% was considered for costs and QALYs. Two times Iran's GDP per capita (800,000,000 IRR = US$5934) was used as the threshold. Finally, due to the uncertainty of some parameters, deterministic and probabilistic sensitivity analyses were carried out.

RESULTS

The base case results showed that the highest cost was for the 'Ribociclib+ Fulvestrant' combination (US$89,629.56), and the lowest price was for the 'Iranian Everolimus + Fulvestrant' combination (US$10,740.09). 'Palbociclib + Fulvestrant' brings about the highest value of 1.456 incremental QALYs compared to other strategies. Finally, the 'Iranian Palbociclib + Fulvestrant' was the cost-effective combination, with an incremental cost-effectiveness ratio (ICER) of US$4,201 compared to other strategies. The base case results were supported by the probabilistic sensitivity analysis. Deterministic sensitivity analysis showed that the cost of Iranian Palbociclib has a threshold of US$582.99.

CONCLUSIONS

The 'Iranian Palbociclib + Fulvestrant' combination was cost-effective in second-line therapy for HR+ HER2- MBC in Iran.

A Phase IIb, single arm, multicenter trial of sacituzumab govitecan in Chinese patients with metastatic triple-negative breast cancer who received at least two prior treatments

Refractory or relapsing metastatic triple-negative breast cancer (mTNBC) has a poor prognosis. Sacituzumab govitecan (SG) is a novel antibody-drug conjugate, targeting human trophoblast cell-surface antigen 2 (Trop-2). This is the first report of SG's efficacy and safety in Chinese patients with mTNBC. EVER-132-001 (NCT04454437) was a multicenter, single-arm, Phase IIb study in Chinese patients with mTNBC who failed ≥2 prior chemotherapy regimens. Eligible patients received 10 mg/kg SG on Days 1 and 8 of each 21-day treatment cycle, until disease progression/unacceptable toxicity. The primary endpoint was objective response rate (ORR) assessed by the Independent Review Committee. Secondary endpoints included: duration of response (DOR), clinical benefit rate (CBR), progression-free survival (PFS), overall survival (OS) and safety. Eighty female Chinese patients (median age 47.6 years; range 24-69.9 years) received ≥1 SG dose with a median of 8 treatment cycles by the cutoff date (August 6, 2021). Median number of prior systemic cancer treatments was 4.0 (range 2.0-8.0). ORR and CBR were reported 38.8% (95% confidence interval [CI]: 28.06-50.30) and 43.8% (95% CI, 32.68-55.30) of patients, respectively. The median PFS was 5.55 months (95% CI, 4.14-N/A). SG-related Grade ≥3 treatment-emergent adverse events (TEAEs) were reported in 71.3%, the most common were neutrophil count decreased (62.5%), white blood cell count decreased (48.8%) and anemia (21.3%); 6.3% discontinued SG because of TEAEs. SG demonstrated substantial clinical activity in heavily pretreated Chinese patients with mTNBC. The observed safety profile was generally manageable.

Evaluation of cytotoxicity, loading, and release activity of paclitaxel loaded-porphyrin based metal-organic framework (PCN-600)

Considering the inducement side impacts and precipitation of continual doses in conventional therapeutic treatments, there is an urgent need in the field of drug delivery for novel designs of biocompatible carriers with wide loading dimensions and particularly the ability to control their drug release. In this work, we succeeded in synthesizing an iron-based organic metal framework based on iron-porphyrin (PCN-600) through a solvothermal method to function as a drug delivery system (DDS). According to SEM results, PCN-600 crystals a hexagonal-rod shaped morphology with the length of 300 nm and width of 100-300 nm. As an anticancer drug, Paclitaxel (PTX) was successfully loaded into the porphyrin-based metal-organic framework (PCN-600) via in-situ encapsulation; the loading efficiency was measured to be about 87.3%. In addition, PTX-encapsulated PCN-600 displayed a controlled and sustained release for up to 24 h of release assessment at the physiological microenvironment of pH = 7.4.

Clinical Efficacy and Whole-Exome Sequencing of Liquid Biopsies in a Phase IB/II Study of Bazedoxifene and Palbociclib in Advanced Hormone Receptor-Positive Breast Cancer

PURPOSE

Sensitivity to endocrine therapy (ET) is critical for the clinical benefit from the combination of palbociclib plus ET in hormone receptor-positive/HER2-negative (HR+/HER2-) advanced breast cancer. Bazedoxifene is a third-generation selective estrogen receptor (ER) modulator and selective ER degrader with activity in preclinical models of endocrine-resistant breast cancer, including models harboring ESR1 mutations. Clinical trials in healthy women showed that bazedoxifene is well tolerated.

PATIENTS AND METHODS

We conducted a phase Ib/II study of bazedoxifene plus palbociclib in patients with HR+/HER2- advanced breast cancer who progressed on prior ET (N = 36; NCT02448771).

RESULTS

The study met its primary endpoint, with a clinical benefit rate of 33.3%, and the safety profile was consistent with what has previously been seen with palbociclib monotherapy. The median progression-free survival (PFS) was 3.6 months [95% confidence interval (CI), 2.0-7.2]. An activating PIK3CA mutation at baseline was associated with a shorter PFS (HR = 4.4; 95% CI, 1.5-13; P = 0.0026), but activating ESR1 mutations did not impact the PFS. Longitudinal plasma circulating tumor DNA whole-exome sequencing (WES; N = 68 plasma samples) provided an overview of the tumor heterogeneity and the subclonal genetic evolution, and identified actionable mutations acquired during treatment.

CONCLUSIONS

The combination of palbociclib and bazedoxifene has clinical efficacy and an acceptable safety profile in a heavily pretreated patient population with advanced HR+/HER2- breast cancer. These results merit continued investigation of bazedoxifene in breast cancer.

UBE2T promotes breast cancer tumor growth by suppressing DNA replication stress

Breast cancer is a leading cause of cancer-related deaths among women, and current therapies benefit only a subset of these patients. Here, we show that ubiquitin-conjugating enzyme E2T (UBE2T) is overexpressed in patient-derived breast cancer samples, and UBE2T overexpression predicts poor prognosis. We demonstrate that the transcription factor AP-2 alpha (TFAP2A) is necessary for the overexpression of UBE2T in breast cancer cells, and UBE2T inhibition suppresses breast cancer tumor growth in cell culture and in mice. RNA sequencing analysis identified interferon alpha-inducible protein 6 (IFI6) as a key downstream mediator of UBE2T function in breast cancer cells. Consistently, UBE2T inhibition downregulated IFI6 expression, promoting DNA replication stress, cell cycle arrest, and apoptosis and suppressing breast cancer cell growth. Breast cancer cells with IFI6 inhibition displayed similar phenotypes as those with UBE2T inhibition, and ectopic IFI6 expression in UBE2T-knockdown breast cancer cells prevented DNA replication stress and apoptosis and partly restored breast cancer cell growth. Furthermore, UBE2T inhibition enhanced the growth-suppressive effects of DNA replication stress inducers. Taken together, our study identifies UBE2T as a facilitator of breast cancer tumor growth and provide a rationale for targeting UBE2T for breast cancer therapies.

Eribulin for the treatment of advanced breast cancer: A prospective observational registry study

OBJECTIVE

Eribulin treatment improved overall survival with predictable toxicities in phase 3 trials of patients with previously treated, locally advanced/metastatic breast cancer. This study (NCT02443428) prospectively observed eribulin-treated patients in real-world clinical practice.

METHODS

This observational multicentre registry study enrolled 76 patients with locally advanced/metastatic breast cancer who had ≤2 prior chemotherapeutic regimens for advanced disease. Eribulin was administered at a 1.23 mg/m² dose (days 1 and 8 of every 21-day cycle). Adverse events (AEs) were monitored and effectiveness was assessed per local practice.

RESULTS

AEs occurred in 98.7% of patients; 88.2% had eribulin-related AEs. The most common AEs were fatigue (64.5%), alopecia (36.8%), nausea (35.5%) and constipation (30.3%). Serious AEs occurred in 42.1% of patients. The most common grade 3/4 AEs were neutropenia (9.2%), febrile neutropenia (9.2%), dyspnoea (5.3%) and pleural effusion (5.3%). No fatal AEs occurred. Dose reductions occurred in 31.6% of patients, 42.1% experienced dose delays and 9.2% discontinued due to worsening condition. There were complete responses in 2.6% and partial responses in 15.8% of patients. Median time to progression and overall survival were 4.0 and 8.3 months, respectively.

CONCLUSION

Eribulin was well tolerated in real-world clinical practice, comparable to safety and effectiveness reported in other clinical trials.

Apatinib plus vinorelbine versus vinorelbine for metastatic triple-negative breast cancer who failed first/second-line treatment: the NAN trial

While therapies such as chemotherapy combined with immunotherapy, sacituzumab govitecan, and PARP inhibitors are available for metastatic TNBC, on disease progression after these therapies, the mainstay of therapy is chemotherapy. Apatinib is a small-molecule tyrosine kinase inhibitor that has promising anti-angiogenesis and antitumor activity for TNBC. We aimed to evaluate the safety and efficacy of adding apatinib to chemotherapy in patients with advanced TNBC with failed first/second-line treatment. A total of 66 patients were randomly assigned, in a 1:1 ratio, to receive vinorelbine or vinorelbine with apatinib in 28-day cycles. The primary endpoint was progression-free survival (PFS). Secondary endpoints included overall survival (OS), overall response rate (ORR) and safety. 33 received apatinib plus vinorelbine and 32 received vinorelbine (1 was withdrawal). Median PFS was significantly longer in the apatinib plus vinorelbine group than in the vinorelbine group (3.9 months vs. 2.0 months; hazard ratio, 1.82; 95% confidence interval [CI], 1.06 to 3.11; P = 0.026). Median OS was 11.5 months with apatinib plus vinorelbine and 9.9 months with vinorelbine (HR,1.01; 95% CI, 0.51 to 1.97; P = 0.985). The ORR was 9.1% in the apatinib plus vinorelbine group and 6.3% in the vinorelbine group (P = 0.667). The most common treatment-related hematologic grade 3–4 adverse events in apatinib plus vinorelbine group, were leukopenia, granulocytopenia, anemia, and thrombocytopenia. no treatment-related nonhematologic grade 4 adverse events or treatment-related deaths were observed. Collectively, adding apatinib to vinorelbine shows a promising benefit in PFS compared to vinorelbine monotherapy, with an excellent toxicity profile, warranting further exploration.

Targeted therapy for breast cancer: An overview of drug classes and outcomes

The last 25 years have seen significant growth in new therapeutic options for breast cancer, termed targeted therapies based on their ability to block specific pathways known to drive breast tumor growth and survival. Introduction of these drugs has been made possible through advances in the understanding of breast cancer biology. While the promise of targeted therapy for breast cancer has been clear for some time, the experience of the clinical use of multiple drugs and drug classes allows us to now present a summary and perspective as to the success and impact of this endeavor. Here we will review breast cancer targeted therapeutics in clinical use. We will provide the rationale for their indications and summarize clinical data in patients with different breast cancer subtypes, their impact on breast cancer progression and survival and their major adverse effects. The focus of this review will be on the development that has occurred within classes of targeted therapies and subsequent impact on breast cancer patient outcomes. We will conclude with a perspective on the role of targeted therapy in breast cancer treatment and highlight future areas of development.

Network meta-analysis of eribulin versus other chemotherapies used as second- or later-line treatment in locally advanced or metastatic breast cancer

BACKGROUND

Eribulin mesylate (ERI; Halaven®) is a microtubule inhibitor approved in the United States for metastatic breast cancer patients with at least two prior chemotherapy regimens for metastatic breast cancer, and in the European Union in locally advanced breast cancer or metastatic breast cancer patients who progressed after at least one chemotherapy for advanced disease. This network meta-analysis compared the efficacy and safety of ERI versus other chemotherapies in this setting.

METHODS

Systematic searches conducted in MEDLINE, Embase, and the Cochrane Central Register of Clinical Trials identified randomized controlled trials of locally advanced breast cancer/metastatic breast cancer chemotherapies in second- or later-line settings. Efficacy assessment included pre-specified subgroup analysis of breast cancer subtypes. Included studies were assessed for quality using the Centre for Reviews and Dissemination tool. Bayesian network meta-analysis estimated primary outcomes of overall survival and progression-free survival using fixed-effect models. Comparators included: capecitabine (CAP), gemcitabine (GEM), ixabepilone (IXA), utidelone (UTI), treatment by physician's choice (TPC), and vinorelbine (VIN).

RESULTS

The network meta-analysis included seven trials. Results showed that second- or later-line patients treated with ERI had statistically longer overall survival versus TPC (hazard ratio [HR]: 0.81; credible interval [CrI]: 0.66-0.99) or GEM+VIN (0.62; 0.42-0.90) and statistically longer progression-free survival versus TPC (0.76; 0.64-0.90), but statistically shorter progression-free survival versus CAP+IXA (1.40; 1.17-1.67) and CAP+UTI (1.61; 1.23-2.12). In triple negative breast cancer, ERI had statistically longer overall survival versus CAP (0.70; 0.54-0.90); no statistical differences in progression-free survival were observed in triple negative breast cancer.

CONCLUSIONS

This network meta-analysis suggests that ERI may provide an overall survival benefit in the overall locally advanced breast cancer/metastatic breast cancer populations and triple negative breast cancer subgroup compared to standard treatments. These findings support the use of ERI in second- or later-line treatment of patients with locally advanced breast cancer/metastatic breast cancer.

The Biological and Biomechanical Role of Transglutaminase-2 in the Tumour Microenvironment

Transglutaminase-2 (TG2) is the most highly and ubiquitously expressed member of the transglutaminase enzyme family and is primarily involved in protein cross-linking. TG2 has been implicated in the development and progression of numerous cancers, with a direct role in multiple cellular processes and pathways linked to apoptosis, chemoresistance, epithelial-mesenchymal transition, and stem cell phenotype. The tumour microenvironment (TME) is critical in the formation, progression, and eventual metastasis of cancer, and increasing evidence points to a role for TG2 in matrix remodelling, modulation of biomechanical properties, cell adhesion, motility, and invasion. There is growing interest in targeting the TME therapeutically in response to advances in the understanding of its critical role in disease progression, and a number of approaches targeting biophysical properties and biomechanical signalling are beginning to show clinical promise. In this review we aim to highlight the wide array of processes in which TG2 influences the TME, focussing on its potential role in the dynamic tissue remodelling and biomechanical events increasingly linked to invasive and aggressive behaviour. Drug development efforts have yielded a range of TG2 inhibitors, and ongoing clinical trials may inform strategies for targeting the biomolecular and biomechanical function of TG2 in the TME.

Comparison of healthcare resource utilization and costs of patients with HR+/HER2- advanced breast cancer treated with ribociclib versus other CDK4/6 inhibitors

AIMS

To assess healthcare resource utilization (HRU) and healthcare costs among women with hormone receptor-positive and human epidermal growth factor receptor 2-negative advanced breast cancer (HR+/HER2- aBC) treated with cyclin-dependent kinases 4 and 6 (CDK4/6) inhibitors.

METHODS

Women with HR+/HER2- aBC, initiating CDK4/6 inhibitor treatment were identified using IBM MarketScan Commercial and Medicare Supplemental databases (Q1/2000-Q3/2018). Based on the first CDK4/6 inhibitor patients received (index therapy), three cohorts were identified: abemaciclib, palbociclib, and ribociclib. The baseline period (six months preceding treatment initiation) was used to describe patient characteristics. All-cause HRU and direct total healthcare costs (medical and pharmacy) from treatment initiation until the earliest of the end of index therapy, continuous health plan enrollment, or data availability, were compared for the ribociclib cohort versus the abemaciclib and palbociclib cohorts, separately, using weighted regression analyses balanced on baseline covariates.

RESULTS

Average age at treatment initiation was ∼60 years and the majority of patients were postmenopausal (abemaciclib: 92%; palbociclib: 92%; ribociclib: 79%). Average follow-up duration was 3.9, 8.8, and 5.9 months for the abemaciclib, palbociclib, and ribociclib cohorts, respectively. After reweighting, HRU was not statistically different between the ribociclib and abemaciclib cohorts, however, the ribociclib cohort incurred significantly lower total healthcare costs (-$5,452; 95% CI: -$8,726; -$1,139, p = .01). Medical costs (driven by outpatient costs) and pharmacy costs (driven by CDK4/6 inhibitor costs) were significantly lower for the ribociclib cohort. Among the reweighted ribociclib and palbociclib cohorts, HRU and total healthcare costs were not statistically different, although the ribociclib cohort had lower outpatient costs per-patient-per-month (-$1,245, 95% CI: -$2,349; -$37, p = .04).

LIMITATIONS

Due to the retrospective, observational design, treatment cohorts were not randomly assigned.

CONCLUSIONS

During CDK4/6 inhibitor therapy, ribociclib patients tended to incur lower medical and pharmacy costs than abemaciclib patients. Among ribociclib and palbociclib patients, HRU and healthcare costs were similar.

Triplet Therapy with Palbociclib, Taselisib, and Fulvestrant in PIK3CA-Mutant Breast Cancer and Doublet Palbociclib and Taselisib in Pathway-Mutant Solid Cancers

Cyclin-dependent kinase 4/6 (CDK4/6) and PI3K inhibitors synergize in PIK3CA-mutant ER-positive HER2-negative breast cancer models. We conducted a phase Ib trial investigating the safety and efficacy of doublet CDK4/6 inhibitor palbociclib plus selective PI3K inhibitor taselisib in advanced solid tumors, and triplet palbociclib plus taselisib plus fulvestrant in 25 patients with PIK3CA-mutant, ER-positive HER2-negative advanced breast cancer. The triplet therapy response rate in PIK3CA-mutant, ER-positive HER2-negative cancer was 37.5% [95% confidence interval (CI), 18.8-59.4]. Durable disease control was observed in PIK3CA-mutant ER-negative breast cancer and other solid tumors with doublet therapy. Both combinations were well tolerated at pharmacodynamically active doses. In the triplet group, high baseline cyclin E1 expression associated with shorter progression-free survival (PFS; HR = 4.2; 95% CI, 1.3-13.1; P = 0.02). Early circulating tumor DNA (ctDNA) dynamics demonstrated high on-treatment ctDNA association with shorter PFS (HR = 5.2; 95% CI, 1.4-19.4; P = 0.04). Longitudinal plasma ctDNA sequencing provided genomic evolution evidence during triplet therapy. SIGNIFICANCE: The triplet of palbociclib, taselisib, and fulvestrant has promising efficacy in patients with heavily pretreated PIK3CA-mutant ER-positive HER2-negative advanced breast cancer. A subset of patients with PIK3CA-mutant triple-negative breast cancer derived clinical benefit from palbociclib and taselisib doublet, suggesting a potential nonchemotherapy targeted approach for this population.This article is highlighted in the In This Issue feature, p. 1.

Phase I study of liposomal irinotecan in patients with metastatic breast cancer: findings from the expansion phase

Purpose

Metastatic breast cancer (mBC) remains incurable and is associated with low survival rates. This study assessed the efficacy and safety of liposomal irinotecan in heavily pretreated patients with mBC, with or without active brain metastases (BM).

Methods

Following the dose escalation phase and determination of recommended phase 2 dose, the expansion phase of this phase I, open-label, non-randomized study, assigned adult women to cohorts based on mBC subtype: cohort 1, hormone receptor +/human epidermal growth factor receptor 2−; cohort 2, triple-negative breast cancer; or cohort 3, any mBC subtype with active BM. Patients received liposomal irinotecan 50 or 70 mg/m² free base every 2 weeks. Here, we report secondary outcomes including best overall response (BOR), objective response rate (ORR), and treatment-emergent adverse events (TEAEs).

Results

For non-central nervous system (non-CNS) disease across all cohorts (intent-to-treat population, N = 29), the ORR was 34.5% (95% confidence interval: 17.94–54.33), with a BOR of partial response in 10 patients (34.5%), stable disease in five (17.2%), progressive disease in 10 (34.5%); four patients were unevaluable (13.8%). The ORR for the CNS cohort was 30.0% (95% confidence interval: 6.67–65.25) using modified Response Evaluation Criteria in Solid Tumors. Common grade 3 or higher TEAEs were diarrhea (27.6%), nausea (17.2%), fatigue (13.8%), asthenia (10.3%), and hypokalemia (10.3%). Serious treatment-related TEAEs were reported in six patients (20.7%). No treatment-related TEAEs resulted in death.

Conclusions

Liposomal irinotecan monotherapy demonstrated antitumor activity in heavily pretreated patients with mBC, with or without BM. The observed safety profile was consistent with that in previous studies.

Clinical trial registration: Trial registration ID NCT01770353.

Electronic supplementary material

The online version of this article (10.1007/s10549-020-05995-7) contains supplementary material, which is available to authorized users.

A Prospective, Randomized, Placebo-Controlled Study of a Combination of Simvastatin and Chemotherapy in Metastatic Breast Cancer

Preclinical studies support the anticancer activity of statins; however, the existing clinical evidence is inconsistent and not definitive. Our study aimed at evaluating a postulated cancer chemo-sensitizing effect of statin (simvastatin) in a cohort of metastatic breast cancer (MBC) patients. We designed a prospective, single-centered, randomized, double blinded, placebo-controlled trial that encompassed MBC patients with an ECOG Performance Status Scale ≤2 and scheduled to be treated with a chemotherapy regimen consisting of carboplatin and vinorelbine every 3 weeks at Al-Baironi Hospital, Damascus, Syria. Patients were enrolled between August 2011 and July 2012 and randomly allocated to receive a 15-day course of either simvastatin (40 mg) or placebo seven days prior to the first day of each chemotherapy cycle and then continued for eight days in each individual cycle. Primary endpoints were objective response rate (ORR) and toxicity, and the secondary endpoint was overall survival (OS). Eighty-two patients met the inclusion criteria and consented. ORR (35% vs. 32.5%) and predominant toxicity and grade ≥3 neutropenia (occurred in 30% vs. 40% of the patients) were not significantly different between simvastatin and placebo groups, respectively. Over a median follow-up of 44 months (range, 10-60), median OS was 15 months in the simvastatin group and 17 the in placebo group (hazard ratio (HR) = 1.16, 95% CI (0.70-1.91), P=0.57). Elevated baseline values of high-sensitivity C-reactive protein (hsCRP >10 mg/l), lactate dehydrogenase (LDH >480 U/L), and chemotherapy being ≥2^nd line were significantly associated with shorter OS for the total cohort in both Univariate and multivariate analyses. Our data prove a safe profile of simvastatin at 40 mg per day combined with carboplatin and vinorelbine in MBC patients but without any beneficial increase of tumor sensitivity to chemotherapy. Moreover, we demonstrated a strong clinical advantage of baseline values of hsCRP and LDH as useful prognostic tools in MBC patients. This trial is registered with ISRCTN12964275.

uPAR antibody (huATN-658) and Zometa reduce breast cancer growth and skeletal lesions

Urokinase plasminogen activator receptor (uPAR) is implicated in tumor growth and metastasis due to its ability to activate latent growth factors, proteases, and different oncogenic signaling pathways upon binding to different ligands. Elevated uPAR expression is correlated with the increased aggressiveness of cancer cells, which led to its credentialing as an attractive diagnostic and therapeutic target in advanced solid cancer. Here, we examine the antitumor effects of a humanized anti-uPAR antibody (huATN-658) alone and in combination with the approved bisphosphonate Zometa (Zoledronic acid) on skeletal lesion through a series of studies in vitro and in vivo. Treatment with huATN-658 or Zometa alone significantly decreased human MDA-MB-231 cell proliferation and invasion in vitro, effects which were more pronounced when huATN-658 was combined with Zometa. In vivo studies demonstrated that huATN-658 treatment significantly reduced MDA-MB-231 primary tumor growth compared with controls. In a model of breast tumor-induced bone disease, huATN-658 and Zometa were equally effective in reducing skeletal lesions. The skeletal lesions were significantly reduced in animals receiving the combination of huATN-658 + Zometa compared with monotherapy treatment. These effects were due to a significant decrease in osteoclastic activity and tumor cell proliferation in the combination treatment group. Transcriptome analysis revealed that combination treatment significantly changes the expression of genes from signaling pathways implicated in tumor progression and bone remodeling. Results from these studies provide a rationale for the continued development of huATN-658 as a monotherapy and in combination with currently approved agents such as Zometa in patients with metastatic breast cancer.

β1-Integrin binding to collagen type 1 transmits breast cancer cells into chemoresistance by activating ABC efflux transporters

Molecular interactions of tumor cells with the microenvironment are regarded as onset of chemotherapy resistance, referred to as cell adhesion mediated drug resistance (CAM-DR). Here we elucidate a mechanism of CAM-DR in breast cancer cells in vitro. We show that human MCF-7 and MDA-MB-231 breast cancer cells decrease their sensitivity towards cisplatin, doxorubicin, and mitoxantrone cytotoxicity upon binding to collagen type 1 (COL1) or fibronectin (FN). The intracellular concentrations of doxorubicin and mitoxantrone were decreased upon cell cultivation on COL1, while cellular cisplatin levels remained unaffected. Since doxorubicin and mitoxantrone are transporter substrates, this refers to ATP binding cassette (ABC) efflux transporter activities. The activation of the transporters BCRP, P-gp and MRP1 was shown by fluorescence assays to distinguish the individual input of these transporters to resistance in presence of COL1 and related to their expression levels by western blot. An ABC transporter inhibitor was able to re-sensitize COL1-treated cells for doxorubicin and mitoxantrone toxicity. Antibody-blocking of β₁-integrin (ITGB1) induced sensitization towards the indicated cytostatic drugs by attenuating the increased ABC efflux activity. This refers to a key role of ITGB1 for matrix binding and subsequent transporter activation. A downregulation of α₂β₁ integrin following COL1 binding appears as clear indication for the relationship between ITGB1 and ABC transporters in regulating resistance formation, while knockdown of ITGB1 leads to a significant upregulation of all three transporters. Our data provide evidence for a role of CAM-DR in breast cancer via an ITGB1 - transporter axis and offer promising therapeutic targets for cancer sensitization.

Current treatment of HER 2+ metastatic breast cancer

Historically, HER2-positive breast cancer had a poor prognosis. The development of molecul ar ther apies that target the HER2 receptor has TR ansformed outcomes. Here, the evidence on Anti-HER2 therapies is summarised.

Two open-label, single arm, non-randomized phase II studies of irinotecan for the treatment of metastatic breast cancer in patients with increased copy number of the topoisomerase I gene

Background

Treatment options in metastatic breast cancer are limited. New therapies preferable with predictive biomarkers are needed. The aim of these trials was to investigate if gene copy number of the topoisomerase 1 gene was predictive of response to the topoisomerase inhibitor irinotecan.

Methods

Two open-label, single-arm phase II studies including HER2 positive and negative patients were conducted. Patients were eligible for inclusion if the primary tumor or a metastatic lesion had increased expression of the topoisomerase 1 gene defined as a TOP1 gene copy number of ≥4 or a TOP1/CEN20 ratio of ≥2. Patients were treated with irinotecan +/− trastuzumab weekly for 4 weeks following 2 weeks break, until progression or unacceptable toxicities. Evaluation scans were performed every 6 weeks. Primary endpoint was clinical benefit rate defined as the fraction of patients with stable disease for ≥4 months.

Results

The pre-planned number of 18 patients in each trial was not reached, thus no formal statistical analysis could be performed. Nine patients with HER2 negative disease and three patients with HER2 positive disease were included. Three patients obtained a partial remission and two patients had SD.

Conclusions

The trials did not include the planned number of patients. No association between gene copy number of the topoisomerase 1 gene and response to irinotecan could be proved, however a clinical benefit was found in 5/12 patients and in 2/3 patients with HER2 positive disease. This could call for further investigation of the drug in the metastatic setting, especially in HER2 positive BC.

Trial registration

Eudract registration numbers 2012–002348-26 and 2012–002347-23. Registration date August 20th 2012.

Development, Validation, and Dissemination of a Breast Cancer Recurrence Detection and Timing Informatics Algorithm

Background

This study developed, validated, and disseminated a generalizable informatics algorithm for detecting breast cancer recurrence and timing using a gold standard measure of recurrence coupled with data derived from a readily available common data model that pools health insurance claims and electronic health records data.

Methods

The algorithm has two parts: to detect the presence of recurrence and to estimate the timing of recurrence. The primary data source was the Cancer Research Network Virtual Data Warehouse (VDW). Sixteen potential indicators of recurrence were considered for model development. The final recurrence detection and timing models were determined, respectively, by maximizing the area under the ROC curve (AUROC) and minimizing average absolute error. Detection and timing algorithms were validated using VDW data in comparison with a gold standard recurrence capture from a third site in which recurrences were validated through chart review. Performance of this algorithm, stratified by stage at diagnosis, was compared with other published algorithms. All statistical tests were two-sided.

Results

Detection model AUROCs were 0.939 (95% confidence interval [CI] = 0.917 to 0.955) in the training data set (n = 3370) and 0.956 (95% CI = 0.944 to 0.971) and 0.900 (95% CI = 0.872 to 0.928), respectively, in the two validation data sets (n = 3370 and 3961, respectively). Timing models yielded average absolute prediction errors of 12.6% (95% CI = 10.5% to 14.5%) in the training data and 11.7% (95% CI = 9.9% to 13.5%) and 10.8% (95% CI = 9.6% to 12.2%) in the validation data sets, respectively, and were statistically significantly lower by 12.6% (95% CI = 8.8% to 16.5%, P < .001) than those estimated using previously reported timing algorithms. Similar covariates were included in both detection and timing algorithms but differed substantially from previous studies.

Conclusions

Valid and reliable detection of recurrence using data derived from electronic medical records and insurance claims is feasible. These tools will enable extensive, novel research on quality, effectiveness, and outcomes for breast cancer patients and those who develop recurrence.

Mechanisms of Matrix-Induced Chemoresistance of Breast Cancer Cells-Deciphering Novel Potential Targets for a Cell Sensitization

Tumor cell binding to microenvironment components such as collagen type 1 (COL1) attenuates the sensitivity to cytotoxic drugs like cisplatin (CDDP) or mitoxantrone (MX), referred to as cell adhesion mediated drug resistance (CAM-DR). CAM-DR is considered as the onset for resistance mutations, but underlying mechanisms remain elusive. To evaluate CAM-DR as target for sensitization strategies, we analyzed signaling pathways in human estrogen-positive MCF-7 and triple-negative MDA-MB-231 breast cancer cells by western blot, proteome profiler array and TOP-flash assay in presence of COL1. β1-Integrins, known to bind COL1, appear as key for mediating COL1-related resistance in both cell lines that primarily follows FAK/PI3K/AKT pathway in MCF-7, and MAPK pathway in MDA-MB-231 cells. Notably, pCREB is highly elevated in both cell lines. Consequently, blocking these pathways sensitizes the cells evidently to CDDP and MX treatment. Wnt signaling is not relevant in this context. A β1-integrin knockdown of MCF-7 cells (MCF-7-β1-kd) reveals a signaling shift from FAK/PI3K/AKT to MAPK pathway, thus CREB emerges as a promising primary target for sensitization in MDA-MB-231, and secondary target in MCF-7 cells. Concluding, we provide evidence for importance of CAM-DR in breast cancer cells and identify intracellular signaling pathways as targets to sensitize cells for cytotoxicity treatment regimes.

Renal toxicity with liposomal doxorubicin in metastatic breast cancer

There is no preferred treatment option for metastatic breast cancer; therefore, treatment should provide palliation, prolong survival, control symptoms, and improve quality of life. Liposomal doxorubicin formulations have been shown to have less alopecia, nausea, vomiting, and myelosuppression than traditional doxorubicin, but more skin toxicities and infusion reactions. Prolonged use of liposomal doxorubicin may be associated with unrecognized or less well-defined toxicities. We report a case of acute kidney injury and progressively worsening chronic kidney disease necessitating dialysis in a patient who received prolonged therapy with liposomal doxorubicin for treatment of metastatic breast cancer. This case report should give caution to providers considering prolonged use of liposomal doxorubicin in the metastatic breast cancer setting as we observed sustained renal toxicity, long past the cessation of treatment.

Predicting efficacy of epirubicin by a multigene assay in advanced breast cancer within a Danish Breast Cancer Cooperative Group (DBCG) cohort: a retrospective-prospective blinded study

Purpose

Anthracyclines remain a cornerstone in the treatment of primary and advanced breast cancer (BC). This study has evaluated the predictive value of a multigene mRNA-based drug response predictor (DRP) in the treatment of advanced BC with epirubicin. The DRP is a mathematical method combining in vitro sensitivity and gene expression with clinical genetic information from > 3000 clinical tumor samples.

Methods

From a DBCG cohort, 140 consecutive patients were treated with epirubicin between May 1997 and November 2016. After patient informed consent, mRNA was isolated from archival formalin-fixed paraffin-embedded primary breast tumor tissue and analyzed using Affymetrix arrays. Using time to progression (TTP) as primary endpoint, the efficacy of epirubicin was analyzed according to DRP combined with clinicopathological data collected retrospectively from patients’ medical records. Statistical analysis was done using Cox proportional hazards model stratified by treatment line.

Results

Median TTP was 9.3 months. The DRP was significantly associated to TTP (P = 0.03). The hazard ratio for DRP scores differing by 50 percentage points was 0.55 (95% CI –0.93, one-sided). A 75% DRP was associated with a median TTP of 13 months compared to 7 months following a 25% DRP. Multivariate analysis showed that DRP was independent of age and number of metastases.

Conclusion

The current study prospectively validates the predictive capability of DRP regarding epirubicin previously shown retrospectively allowing the patients predicted to be poor responders to choose more effective alternatives. Randomized prospective studies are needed to demonstrate if such an approach will lead to increased overall survival.

Clinical implication of tumor mutational burden in patients with HER2-positive refractory metastatic breast cancer

This study explored the clinical implications of tumor mutational burden (TMB) in a well-defined HER2-positive metastatic breast cancer (MBC) patient population who had been previously treated but had subsequent disease progression. Whole exome sequencing was performed on formalin-fixed paraffin-embedded tumor samples and matched normal tissue. Among the 46 patients, 13 (28.3%) were estrogen receptor-positive and nine (19.6%) were progesterone receptor-positive by immunohistochemistry analysis. Twenty patients (43.5%) had recurrent MBC compared with de novo MBC (n = 26, 56.5%). Sixteen patients (34.6%) demonstrated more than 100 somatic non-synonymous SNV mutations, which was predefined as a high TMB. The median follow-up duration was 57.5 months. The median overall survival (mOS) differed significantly between low and high TMB status (44.9 months vs. 85.8 months, respectively, p = 0.016). In a multivariate Cox regression analysis, TMB was the only independent prognostic factor for good metastatic overall survival after adjusting for age and recurrence (Hazard ratio [HR] = 0.32, 95% confidence interval [CI], 0.103-0.998, p = 0.049). These data suggest that high TMB may be a prognostic marker for predicting good overall survival for patients undergoing conventional HER2-directed treatments and chemotherapy. Further, future clinical trials harnessing TMB may benefit by identifying an appropriate population who may have a favorable response to immunotherapy after recurrence following HER2-directed treatments.

Quality-Adjusted Survival With nab-Paclitaxel Versus Standard Paclitaxel in Metastatic Breast Cancer: A Q-TWiST Analysis

BACKGROUND

In this analysis we compared quality-adjusted survival outcomes between nab-paclitaxel (nab-P) and standard paclitaxel (Pac) using data from the nab-P phase III registration trial in metastatic breast cancer.

PATIENTS AND METHODS

Quality-adjusted overall survival was estimated using the quality-adjusted time without symptoms or toxicity (Q-TWiST) approach. Overall survival was partitioned into time without progression/Grade ≥ 3 adverse events (AEs) toxicity (TWiST), time with Grade ≥ 3 AE toxicity (TOX), and time after relapse (REL). Q-TWiST was calculated by multiplying mean time in each health state by its assigned utility (base-case utility values: time without symptoms of disease progression or toxicity of Grade ≥ 3 adverse events [TWiST] = 1.0, TOX = 0.5, and REL = 0.5). In threshold analyses, TOX and REL varied from 0.0 to 1.0 whereas TWiST was maintained at 1.0. Comparisons were made for the intent-to-treat population and the subset of patients initiating the study drugs as second or subsequent lines (2L+) of chemotherapy (per approved nab-P indication; 2L+ subpopulation). A ≥ 15% relative Q-TWiST gain (vs. mean Pac overall survival) was considered clearly clinically important.

RESULTS

In the intent-to-treat population, nab-P (n = 229) versus Pac (n = 225) resulted in nonsignificant gains of 1.4 months of mean Q-TWiST (11.6 vs. 10.2 months; 95% confidence interval [CI], -0.03 to 2.8). In the 2L+ subpopulation, nab-P (n = 132) versus Pac (n = 136) resulted in a statistically significant gain of 2.2 months of mean Q-TWiST (10.5 vs. 8.4 months; 95% CI, 0.6-3.8), with a 17.1% relative Q-TWiST gain (threshold analysis range, 14.0%-19.5%, both figures significant).

CONCLUSION

In its approved indication for metastatic breast cancer, nab-P showed a statistically significant and clearly clinically important improvement in quality-adjusted survival time versus Pac in the 2L+ subpopulation.

Young breast cancer patients who develop distant metastasis after surgery have better survival outcomes compared with elderly counterparts

To investigate the recurrence pattern and subsequent survival outcomes in young breast cancer population, 483 young patients (≤ 35) and 739 elderly patients (≥ 65), who received mastectomy or breast-conserving surgery from 2008 to 2012, were included in this study. The young population presented with a higher rate of pathologic tumor stage (P < 0.001), positive pathologic lymph node (P < 0.001), grade III tumors (P < 0.001), and lymphovascular invasion (P < 0.001). With a median follow-up of 56.5 months, young patients had a significantly lower 5-year disease-free survival (73.7% vs 83.4%, P = 0.001), while no difference in 5-year overall survival was observed (91.7% vs 91.7%, P = 0.721). The 5-year cumulative incidences of locoregional relapse (8.9% vs 4.3%, P = 0.009) and distant metastasis (18.8% vs 9.5%, P < 0.001) were significantly higher in the young population. However, for patients with distant metastasis, the survival outcomes were significantly better in the young patients (5-year overall survival since diagnosis: 60.0% vs 47.3%, P = 0.025; 5-year overall survival after recurrence: 31.0% vs 24.3%, P = 0.001). Young breast cancer patients present with more aggressive clinicopathological features and have poor prognosis compared with elderly. But young patients with distant metastasis might have better survival outcomes.

Factors associated with prolonged time to treatment failure with fulvestrant 500 mg in patients with post-menopausal estrogen receptor-positive advanced breast cancer: a sub-group analysis of the JBCRG-C06 Safari study

OBJECTIVE

The JBCRG-C06 Safari study showed that earlier fulvestrant 500 mg (F500) use, a longer time from diagnosis to F500 use, and no prior palliative chemotherapy were associated with significantly longer time to treatment failure (TTF) among Japanese patients with estrogen receptor-positive (ER+) advanced breast cancer (ABC). The objective of this sub-group analysis was to further examine data from the Safari study, focusing on ER + and human epidermal growth factor receptor-negative (HER2-) cases.

METHODS

The Safari study (UMIN000015168) was a retrospective, multi-center cohort study, conducted in 1,072 patients in Japan taking F500 for ER + ABC. The sub-analysis included only patients administered F500 as second-line or later therapy (n = 960). Of these, 828 patients were HER2-. Results Multivariate analysis showed that advanced age (≥65 years; p = .035), longer time (≥3 years) from ABC diagnosis to F500 use (p < .001), no prior chemotherapy (p < .001), and F500 treatment line (p < .001) were correlated with prolonged TTF (median = 5.39 months).

CONCLUSIONS

In ER+/HER2- patients receiving F500 as a second-line or later therapy, treatment line, advanced age, no prior palliative chemotherapy use, and a longer period from ABC diagnosis to F500 use were associated with longer TTF.

Foreword

Delivering multifaceted, quality care to women living with metastatic breast cancer (MBC) demands professional competence and an advanced level of practice. The breast cancer nursing community is evolving to meet this need as more nurses are appointed specifically for the advanced disease setting, while nurses who previously worked only in early stage disease are now delivering care across the disease trajectory, fulfilling a 'diagnosis to death' nursing model. The MBC nursing community, linked by UK charity Breast Cancer Care and the Roche Nursing Matters programme, offers forums for learning, and provides ongoing support to this group of nurses. This supplement has been commissioned by Roche Products Ltd to continue supporting nurses who treat patients with MBC by sharing learning and best practice, with a view to encouraging innovation in service delivery.

Improving patient care: expert nursing and service development

Early access to a clinical nurse specialist will ensure that patients receive the interventions and support they need. Optimum outcomes will be achieved if specialists work in collaboration with a wider team.

Introduction

Metastatic breast cancer (MBC), also known as secondary breast cancer (SBC), occurs when cells from the primary breast tumour metastasise from the breast to other parts of the body via the blood or lymphatic systems. The disease may range from limited bone metastases to widespread and life-threatening metastases in visceral organs such as the liver, lung and brain (National Institute for Health and Care Excellence (NICE), 2009; 2014). MBC is incurable, and the primary goal of treatment is to extend life and palliate symptoms, while preserving quality of life (NICE, 2009; 2014).

Defining what matters most to patients

Advanced communication skills are needed to identify patients' needs and provide the psychological and social support they require. Meanwhile, early access to palliative care will improve symptom control.

Outcomes of fulvestrant therapy among japanese women with advanced breast cancer: a retrospective multicenter cohort study (JBCRG-C06; Safari)

PURPOSE

This retrospective study evaluated the effect of clinical background and treatment line on time to treatment failure (TTF) in advanced/metastatic breast cancer (AMBC) patients receiving F500 in Japan (UMIN 000015168).

METHODS

Patients who commenced F500 treatment were registered at 16 sites in Japan. Correlations between baseline clinicopathological factors, treatment line, and TTF were investigated by Kaplan-Meier analysis. TTF data were analyzed using univariate analysis and multivariate analysis with a Cox proportional hazards model.

RESULTS

Data for 1072 patients were available; 1031 patients (96.2%) were evaluable for efficacy. F500 was administered as first-line treatment in 2.0%, second-line in 22.7%, third-line in 26.7%, and ≥fourth-line in 48.6% patients. Median TTF was 5.4 months. Multivariate analysis found that earlier F500 use (first and second vs. third vs. ≥fourth line; hazard ratio (HR) = 0.80, 95% confidence interval (CI) 0.74-0.86; P < 0.001), longer period from AMBC diagnosis to F500 use (≥3 vs. <3 years; HR 0.60, 95% CI 0.51-0.70; P < 0.001), and no prior palliative chemotherapy administered for unresectable or metastatic breast cancer (no vs. yes; HR 0.69, 95% CI 0.60-0.80; P < 0.001) were associated with significantly longer TTF. Among 691 patients, where information on histologic/nuclear grade was available, a low grade was also associated with a longer TTF, but this finding was not maintained among patients with recurrent breast cancer (N = 558). Among women with recurrent breast cancer, a longer DFI between a patient's initial breast cancer diagnosis and their recurrence was associated with a longer TTF on F500 therapy.

CONCLUSIONS

Our study showed that treatment period of F500 was longer when used in earlier-line treatment. For patients on F500, TTF was also longer for patients who had not received prior palliative chemotherapy and for those who had a longer period from their AMBC diagnosis to F500 use.

Efficacy and safety of doublet versus single agent as salvage treatment for metastatic breast cancer pretreated with anthracyclines and taxanes: a systematic review and meta-analysis

AIM

To perform a systematic review and meta-analysis of randomized controlled trials to compare the efficacy and safety of doublet versus single agent as salvage treatment for pretreated metastatic breast cancer.

METHODS

A comprehensive literature search was performed to identify relevant randomized controlled trials (RCTs). All clinical studies were independently identified by two authors for inclusion. Demographic data, treatment regimens, objective response rate (ORR), and progression-free survival (PFS) and overall survival (OS) were extracted and analyzed using Comprehensive MetaAnalysis software (Version 2.0).

RESULTS

Thirteen RCTs involving 4878 pretreated metastatic breast cancer patients were ultimately identified. The pooled results demonstrated that doublet combination therapy significantly improved ORR (RR 1.13, 95% CI: 1.01-1.27, p < .001) and PFS (hazard ration [HR] 0.83, 95% CI: 0.73-0.96, p = .011), but not OS (HR 0.93, 95% CI: 0.86-1.01, p = .065). Similar results were observed in sub-group analysis according to treatment regimens. Additionally, more incidences of grade 3 or 4 myelosuppression toxicities nausea and fatigue were observed in doublet combination therapy.

CONCLUSIONS

In comparison with a single agent alone, doublet combination therapy as salvage treatment for pretreated metastatic breast cancer patients significantly improves ORR and PFS, but not OS. Further studies are recommended to identify patients who will most likely benefit from the appropriate doublet combination therapy.

Comparison of the Therapeutic Efficacy of the Early and the Delayed Use of Vinorelbine-Based Regimens for Patients with Advanced Breast Cancer

BACKGROUND

The aim of this study was to evaluate the efficacy of vinorelbine-based regimens as first-, second- and more-line therapies in advanced breast cancer (ABC) and to analyze the best timing of vinorelbine treatment.

METHODS

A total of 71 ABC patients were retrospectively reviewed. Of these, 35 patients were treated with vinorelbine-based regimens as first-line chemotherapy, and 36 patients were treated with vinorelbine-based regimens as second-line or more-line therapy. The primary end point of the study was progression-free survival (PFS).

RESULTS

No difference was found in baseline characteristics between the two groups (p > 0.1 for all comparisons). There was a significant difference in the objective response rate (ORR; p = 0.006) and clinical benefit rate (CBR; p = 0.013) between the first-line group and the second- or more-line groups. In the vinorelbine first-line group, the ORR was 68.6% (24 patients), and in the second-line or more-line groups the ORR was 36.1% (13 patients). A significant difference in PFS between the first-line group and the second-line or more-line groups was also observed (p = 0.030). The median PFS in the overall population was 6.3 ± 1.32 months (95% CI 3.69-8.90). The median PFS was 11.1 ± 3.76 months (95% CI 3.73-18.47) in the first-line group compared with 5.2 ± 1.35 months (95% CI 2.54-7.85) in the second-line or more-line groups. In patients treated with vinorelbine-trastuzumab combination as the first-line therapy, a complete response was observed in 1 patient (12.5%) and partial response in 5 patients (62.5%), giving an ORR of 75.0%. Progressive disease was observed in 1 patient (12.5%), and stable disease in 1 patient (12.5%), leading to a CBR of 87.5%. The median PFS was 13.8 ± 2.75 months (95% CI 8.42-19.18), and median OS was 37.0 ± 11.6 months (95% CI 14.18-59.82). No significant difference was found in overall survival (OS) between the groups (p = 0.612).

CONCLUSION

For ABC patients, no significant difference in median OS was found between the early use and delayed use of vinorelbine-based regimens, but the short-term efficacy and PFS of vinorelbine-based regimens were significantly better in the early use group than in the delayed use group.

Reactive oxygen species-mediated synergistic and preferential induction of cell death and reduction of clonogenic resistance in breast cancer cells by combined cisplatin and FK228

Safe and effective combination chemotherapy regimens against breast cancer are lacking. We used our cellular system, consisting of the non-cancerous human breast epithelial MCF10A cell line and its derived tumorigenic, oncogenic H-Ras-expressing, MCF10A-Ras cell line, to investigate the effectiveness of a combination chemotherapy regimen in treating breast cancer cells using two FDA-approved agents, cisplatin and FK228. Cisplatin and FK228 significantly, synergistically, and preferentially induced death and reduced drug resistance of MCF10A-Ras versus MCF10A cells. The ERK-Nox-ROS pathway played a major role in both synergistic cell death induction and GSH-level reduction, which contributed to the synergistic suppression of drug resistance in cells. Enhancement of the Ras-ERK-Nox pathway by combined cisplatin and FK228 significantly increased ROS levels, leading to induction of death, reduction of drug resistance, and induction of DNA damage and oxidation in cancerous MCF10A-Ras cells. Furthermore, synergistic induction of cell death and reduction of drug resistance by combined cisplatin and FK228 in breast cells is independent of their estrogen receptor status. Our study suggests that combined cisplatin and FK228 should be considered in clinical trials as a new regimen for therapeutic control of breast cancers.

Hormonal therapy might be a better choice as maintenance treatment than capecitabine after response to first-line capecitabine-based combination chemotherapy for patients with hormone receptor-positive and HER2-negative, metastatic breast cancer

Background

Both hormonal therapy (HT) and maintenance capecitabine monotherapy (MCT) have been shown to extend time to progression (TTP) in patients with metastatic breast cancer (MBC) after failure of taxanes and anthracycline-containing regimens. However, no clinical trials have directly compared the efficacy of MCT and HT after response to first-line capecitabine-based combination chemotherapy (FCCT) in patients with hormone receptor (HR)-positive and human epidermal growth factor receptor 2 (HER2)-negative breast cancer.

Methods

We retrospectively analyzed the charts of 138 HR-positive and HER2-negative MBC patients who were in non-progression status after FCCT and who were treated between 2003 and 2012 at the Cancer Institute and Hospital, Chinese Academy of Medical Sciences, in Beijing, China. The median number of first-line chemotherapy cycles was 6 (range, 4–8); combined agents included taxanes, vinorelbine, or gemcitabine. Of these 138 patients, 79 received MCT, and 59 received HT. Single-agent capecitabine was administered at a dose of 1250 mg/m² twice daily for 14 days, followed by a 7-day rest period, repeated every 3 weeks. Of the 59 patients who received HT, 37 received aromatase inhibitors (AIs), 8 received selective estrogen receptor modulators (SERMs), and 14 received goserelin plus either AIs or SERMs. We then compared the MCT group and HT group in terms of treatment efficacy.

Results

With a median follow-up of 43 months, patients in the HT group had a much longer TTP than patients in the MCT group (13 vs. 8 months, P = 0.011). When TTP was adjusted for age, menopausal status, Karnofsky performance status score, disease-free survival, site of metastasis, number of metastatic sites, and response status after FCCT, extended TTP was still observed for patients in the HT group (hazard ratio: 0.63; 95% confidence interval: 0.44–0.93; P = 0.020). We also observed a trend of overall survival advantage for patients in the HT group vs. patients in the MCT group, but the difference was not significant (43 vs. 37 months, P = 0.400). In addition, patients in the HT group generally tolerated the treatment well, whereas patients in the MCT group experienced grades 3–4 adverse events, the most frequent of which were hand-foot syndrome (15.8%) and hematologic abnormalities (7.6%).

Conclusion

For HR-positive and HER2-negative MBC patients, HT might be considered a treatment after response to FCCT but prior to MCT as a long-term administration.

Targeted chemotherapy with nanoparticle albumin-bound paclitaxel (nab-paclitaxel) in metastatic breast cancer: which benefit for which patients?

The therapeutic goals in metastatic breast cancer (MBC) remain palliative in nature, aimed at controlling symptoms, improving or maintaining quality of life and prolonging survival. The advent of new drugs and new formulations of standard agents has led to better outcomes in patients with advanced or metastatic disease. These developments have also allowed a tailored therapeutic approach, in which the molecular biology of the tumour, the treatment history, and patient attitudes are taken into account in the decision-making process. Targeting drug delivery to the tumour is a promising mean of increasing the therapeutic index of highly active agents such as the taxanes, and nanoparticle albumin-bound paclitaxel (nab-paclitaxel), the first nanotechnology-based drug developed in cancer treatment, is one such advance. Data from randomized trials support the efficacy of single-agent nab-paclitaxel as first-line and further treatment lines in MBC at the registered 3-weekly schedule of 260 mg/m(2), but emerging evidence suggests its activity as a weekly regimen or combined with other agents in various clinical scenarios. Thus, nab-paclitaxel seems to offer flexibility in terms of dosing schedules, allowing physicians to tailor the dose according to different clinical situations. This paper reviews the clinical trial background for nab-paclitaxel in MBC, focusing on specific 'difficult-to-treat' patient populations, such as taxane-pretreated or elderly women, as well as those with triple-negative, HER2-positive and poor-prognostic-factors disease. Moving beyond evidence-based information, 'real life' available experiences are also discussed with the aim of providing an update for daily clinical practice.

Second-line single-agent chemotherapy in human epidermal growth factor receptor 2-negative metastatic breast cancer: A systematic review

BACKGROUND

No 'gold standard' exists for single-agent chemotherapy of human epidermal growth factor receptor 2-negative (HER2-negative) metastatic breast cancer (MBC) in the second-line. The objective of this systematic review is to identify and appraise overall survival (OS), progression-free survival (PFS), time to progression (TTP) and Grade ≥3 adverse event evidence for single-agent chemotherapy in this setting.

METHODS

MEDLINE, Embase and the Cochrane Library were searched to October 2013, and PubMed October 2013 to November 2014. Electronic database searches were supplemented with hand searching of reference lists and conferences. Eligible randomised controlled trials (RCTs) employed at least one single-agent chemotherapy treatment, enrolled HER2-negative or unselected MBC patients who had progressed following first-line chemotherapy within the metastatic setting, and reported outcomes of interest for the second-line setting.

RESULTS

Fifty-three RCTs were included in total, with most containing mixed populations by HER2 status and treatment line. Fourteen studies reported data specifically for second- and later-line treatment within the metastatic setting. Median overall survival (OS) in most trials was 8-13 months. Only one trial reported a significant difference between studied interventions in the second-line metastatic setting: nab-paclitaxel (n=131) conferred a statistically significant OS advantage vs. three-weekly paclitaxel (n=136) (median OS 13.0 vs. 10.7 months, respectively; hazard ratio 0.73, p=0.024) and improved overall safety.

CONCLUSION

One RCT demonstrated significant benefit in this setting in confirmed HER2-negative MBC alongside favourable safety. Treatment line terminology was imprecise. To reliably inform patient treatment decisions, quality-of-life data are needed and precise OS estimation according to underlying patient characteristics.

Overweight and obesity predict better overall survival rates in cancer patients with distant metastases

Recent studies conducted in patients with chronic diseases have reported an inverse association between body mass index (BMI) and mortality. However, the question as to whether BMI may predict prognosis in patients with metastatic cancer remains open. We therefore designed the current retrospective study to investigate the potential association between BMI and overall survival (OS) in patients with distant metastases (DM) and a favorable performance status. Between 2000 and 2012, a total of 4010 cancer patients with DM who required radiotherapy (RT) and had their BMI measured at the initiation of RT were identified. The relation between BMI and OS was examined by univariate and multivariable analysis. The median OS time was 3.23 months (range: 0.1–122.17) for underweight patients, 6.08 months (range: 0.03–149.46) for normal‐weight patients, 7.99 months (range: 0.07–158.01) for overweight patients, and 12.49 months (range, 0.2–164.1) for obese patients (log‐rank: P < 0.001). Compared with normal‐weight patients, both obese (HR = 0.676; 95% P < 0.001) and overweight individuals (HR = 0.84; P < 0.001) had a reduced risk of all‐cause mortality in multivariable analysis. Conversely, underweight patients had a significantly higher risk of death from all causes (HR = 1.41; P < 0.001). Overweight and obesity are independent predictors of better OS in metastatic patients with a good performance status. Increased BMI may play a role to identify metastatic patients with superior survival outcome and exhibit a potential to encourage aggressive management in those patients even with metastases.

Molecular characterization of irinotecan (SN-38) resistant human breast cancer cell lines

Background

Studies in taxane and/or anthracycline refractory metastatic breast cancer (mBC) patients have shown approximately 30 % response rates to irinotecan. Hence, a significant number of patients will experience irinotecan-induced side effects without obtaining any benefit. The aim of this study was to lay the groundwork for development of predictive biomarkers for irinotecan treatment in BC.

Methods

We established BC cell lines with acquired or de novo resistance to SN-38, by exposing the human BC cell lines MCF-7 and MDA-MB-231 to either stepwise increasing concentrations over 6 months or an initial high dose of SN-38 (the active metabolite of irinotecan), respectively. The resistant cell lines were analyzed for cross-resistance to other anti-cancer drugs, global gene expression, growth rates, TOP1 and TOP2A gene copy numbers and protein expression, and inhibition of the breast cancer resistance protein (ABCG2/BCRP) drug efflux pump.

Results

We found that the resistant cell lines showed 7–100 fold increased resistance to SN-38 but remained sensitive to docetaxel and the non-camptothecin Top1 inhibitor LMP400. The resistant cell lines were characterized by Top1 down-regulation, changed isoelectric points of Top1 and reduced growth rates. The gene and protein expression of ABCG2/BCRP was up-regulated in the resistant sub-lines and functional assays revealed BCRP as a key mediator of SN-38 resistance.

Conclusions

Based on our preclinical results, we suggest analyzing the predictive value of the BCRP in breast cancer patients scheduled for irinotecan treatment. Moreover, LMP400 should be tested in a clinical setting in breast cancer patients with resistance to irinotecan.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-016-2071-1) contains supplementary material, which is available to authorized users.

Antitumor activity of Cetuximab in combination with Ixabepilone on triple negative breast cancer stem cells

Background

Developing novel strategies against treatment-resistant triple negative breast cancer (TNBC) cells remains a significant challenge. The ErbB family, including epidermal growth factor receptor (EGFR), plays key roles in metastasis, tumorigenesis, cell proliferation, and drug resistance. Recently, these characteristics have been linked to a small subpopulation of cells classified as cancer stem cells (CSC) which are believed to be responsible for tumor initiation and maintenance. Ixabepilone is a new generation microtubule-stabilizing agent, which has been expected to be more efficacious than conventional taxanes. Here we aim to investigate whether the EGFR monoclonal antibody Cetuximab, in combination with Ixabepilone, is more effective in eliminating CSC populations compared to chemotherapy alone in TNBC.

Methods

Representative TNBC cell lines (MDA-MB-231 and SUM159) were used to evaluate breast CSC populations. We used fluorescence-activated cell sorter analysis (CD44⁺ and CD24^-/low, or Aldefluor⁺) and a self-renewal assay called mammosphere formation efficiency (MSFE) to measure CSC population size after treatment with Cetuximab, or Cetuximab plus Ixabepilone in vitro.

Results

Although there was no significant decrease in cell viability, Cetuximab reduced MSFE and the CSC population in breast cancer cells in vitro and in vivo through inhibition of autophagy. Also, SUM159 and MDA-MB-231 orthotopic tumors demonstrated partial response to Centuximab or Ixabepilone monotherapy; however, the effect of the combination treatment was significant only in SUM159 tumors (p <0.0001), when compared to Ixabepilone alone.

Conclusions

Overall, our findings demonstrate that EGFR-targeted therapy by Cetuximab effectively reduces the CSC population in TNBC tumors. However, combination therapy with Ixabepilone may be effective only in a small subset of TNBCs, warranting further investigation of alternative approaches to target multiple pathways for TNBC treatment.

Electronic supplementary material

The online version of this article (doi:10.1186/s13058-015-0662-4) contains supplementary material, which is available to authorized users.

Benzyl butyl phthalate increases the chemoresistance to doxorubicin/cyclophosphamide by increasing breast cancer-associated dendritic cell-derived CXCL1/GROα and S100A8/A9

Phthalates are used as plasticizers in the manufacture of flexible vinyl, which is used in food contact applications. Phthalates have been demonstrated to have an adverse impact on human health, particularly in terms of cancer development. In the present study, we showed for the first time that benzyl butyl phthalate (BBP) potentiates the effect of tumor‑associated dendritic cells (TADCs) on the chemoresistance of breast cancer. Specific knockdown analysis revealed that S100A9 is the major factor responsible for the chemoresistance of doxorubicin/cyclophosphamide induced by BBP-stimulated TADCs in breast cancer. BBP exposure also increased tumor infiltrating myeloid-derived suppressor cell (MDSC) secretion of S100A8/A9, thereby exacerbating the resistance of breast cancer to doxorubicin with cyclophosphamide. In addition, BBP also stimulated the production of CXCL1/GROα by TADCs, which increased the angiogenesis of breast cancer in a mouse model. Inhibition of CXCL1/GROα by a neutralizing antibody, decreased the BBP-induced angiogenesis induced by BBP after chemotherapy in the mouse model. These results, for the first time, provide evidence that BBP influences the efficacy of chemotherapy by remodeling the tumor microenvironment of breast cancer.

Real-world effectiveness of everolimus-based therapy versus endocrine monotherapy and chemotherapy in patients of HR+/HER2- breast cancer with liver metastasis in the USA

OBJECTIVE

This study investigated the comparative effectiveness of everolimus-based therapy (EVE) versus endocrine monotherapy (ET) and chemotherapy (CT) in the treatment of hormone-receptor-positive human-epidermal-growth-factor-receptor-2-negative (HR+/HER2-) metastatic breast cancer (mBC) patients with liver metastasis.

METHODS

Medical charts of patients treated by community oncologists were examined. Eligible patients included postmenopausal women with HR+/HER2- mBC with liver metastasis who received EVE, ET or CT between 1 July 2012 and 15 April 2013 after non-steroidal aromatase inhibitor use. Time on treatment (TOT) and progression-free survival (PFS) were compared between EVE and ET or CT using Kaplan-Meier analyses and Cox proportional hazards models.

RESULTS

Among the 202 patients in the study, 82 received EVE, 49 ET, and 71 CT. After adjusting for baseline characteristics, EVE was associated with significantly longer TOT than ET (hazard ratio [HR]: 0.49; 95% CI: 0.28 - 0.86) or CT (HR: 0.35; 95% CI: 0.22 - 0.55), and significantly longer PFS than ET (HR: 0.48; 95% CI: 0.27 - 0.87). PFS was not significantly different with EVE versus CT (HR: 0.76; 95% CI: 0.44 - 1.32).

CONCLUSIONS

EVE had significantly longer TOT and PFS than ET and longer TOT than CT among postmenopausal HR+/HER2- mBC patients with liver metastasis.

A network meta-analysis of everolimus plus exemestane versus chemotherapy in the first- and second-line treatment of estrogen receptor-positive metastatic breast cancer

The goal of this study was to compare the efficacy and toxicity of chemotherapy to exemestane plus everolimus (EXE/EVE) through a network meta-analysis (NMA) of randomized controlled trials. NMA methods extend standard pairwise meta-analysis to allow simultaneous comparison of multiple treatments while maintaining randomization of individual studies. The method enables "direct" evidence (i.e., evidence from studies directly comparing two interventions) and "indirect" evidence (i.e., evidence from studies that do not compare the two interventions directly) to be pooled under the assumption of evidence consistency. We used NMA to evaluate progression-free survival (PFS) and time to progression (TTP) curves in 34 studies, and response rate (RR) and the hazard ratios (HRs) of the PFS/TTP in 36 studies. A number needed to treat (NNT) analysis was also performed as well as descriptive comparison of reported toxicities. The NMA for PFS/TTP curves and for HR shows EXE/EVE is more efficacious than capecitabine plus sunitinib, CMF, megestrol acetate and tamoxifen, with an average of related-PFS/TTP difference ranging from about 10 months for capecitabine plus sunitinib to more than 6 months for tamoxifen. The NMA for overall RR shows that EXE/EVE provides a better RR than bevacizumab plus capecitabine, capecitabine, capecitabine plus sorafenib, capecitabine plus sunitinib, CMF, gemcitabine plus epirubicin plus paclitaxel, EVE plus tamoxifen, EXE, FEC, megestrol acetate, mitoxantrone, and tamoxifen. Finally, the NMA for NNT shows that EXE/EVE is more beneficial as compared to BMF, capecitabine, capecitabine plus sunitinib, CMF, FEC, megestrol acetate, mitoxantrone, and tamoxifen. The combination of EXE/EVE as first- or second-line therapy for ER+ve/HER2-ve metastatic breast cancer is more efficacious than several chemotherapy regimens that were reported in the literature. Toxicities also favored EXE/EVE in most instances.