Outcome of patients with HER2-positive breast cancer treated with or without adjuvant trastuzumab in the Finland Capecitabine Trial (FinXX)

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.

HER2Δ16 Engages ENPP1 to Promote an Immune-Cold Microenvironment in Breast Cancer

The tumor-immune microenvironment (TIME) is a critical determinant of therapeutic response. However, the mechanisms regulating its modulation are not fully understood. HER2Δ16, an oncogenic splice variant of the HER2, has been implicated in breast cancer and other tumor types as a driver of tumorigenesis and metastasis. Nevertheless, the underlying mechanisms of HER2Δ16-mediated oncogenicity remain poorly understood. Here, we show that HER2∆16 expression is not exclusive to the clinically HER2+ subtype and associates with a poor clinical outcome in breast cancer. To understand how HER2 variants modulated the tumor microenvironment, we generated transgenic mouse models expressing either proto-oncogenic HER2 or HER2Δ16 in the mammary epithelium. We found that HER2∆16 tumors were immune cold, characterized by low immune infiltrate and an altered cytokine profile. Using an epithelial cell surface proteomic approach, we identified ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1) as a functional regulator of the immune cold microenvironment. We generated a knock-in model of HER2Δ16 under the endogenous promoter to understand the role of Enpp1 in aggressive HER2+ breast cancer. Knockdown of Enpp1 in HER2Δ16-derived tumor cells resulted in decreased tumor growth, which correlated with increased T-cell infiltration. These findings suggest that HER2Δ16-dependent Enpp1 activation associates with aggressive HER2+ breast cancer through its immune modulatory function. Our study provides a better understanding of the mechanisms underlying HER2Δ16-mediated oncogenicity and highlights ENPP1 as a potential therapeutic target in aggressive HER2+ breast cancer.

Capecitabine for hormone receptor-positive versus hormone receptor-negative breast cancer

BACKGROUND

Retrospective analyses suggest that capecitabine may carry superior activity in hormone receptor-positive relative to hormone receptor-negative metastatic breast cancer. This review examined the veracity of that finding and explored whether this differential activity extends to early breast cancer.

OBJECTIVES

To assess effects of chemotherapy regimens containing capecitabine compared with regimens not containing capecitabine for women with hormone receptor-positive versus hormone receptor-negative breast cancer across the three major treatment scenarios: neoadjuvant, adjuvant, metastatic.

SEARCH METHODS

On 4 June 2019, we searched the Cochrane Breast Cancer Specialised Register; the Cochrane Central Register of Controlled Trials (CENTRAL; 2019, Issue 5) in the Cochrane Library; MEDLINE; Embase; the World Health Organization International Clinical Trials Registry Platform; and ClinicalTrials.gov.

SELECTION CRITERIA

Randomised controlled trials looking at chemotherapy regimens containing capecitabine alone or in combination with other agents versus a control or similar regimen without capecitabine for treatment of breast cancer at any stage. The primary outcome measure for metastatic and adjuvant trials was overall survival (OS), and for neoadjuvant studies pathological complete response (pCR).

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed risk of bias and certainty of evidence using the GRADE approach. Hazard ratios (HRs) were derived for time-to-event outcomes, and odds ratios (ORs) for dichotomous outcomes, and meta-analysis was performed using a fixed-effect model.

MAIN RESULTS

We included 26 studies with outcome data by hormone receptor: 12 metastatic studies (n = 4325), 6 neoadjuvant trials (n = 3152), and 8 adjuvant studies (n = 13,457). Capecitabine treatment was added in several different ways across studies. These could be classified as capecitabine alone compared to another treatment, capecitabine substituted for part of the control chemotherapy, and capecitabine added to control chemotherapy. In the metastatic setting, the effect of capecitabine was heterogenous between hormone receptor-positive and -negative tumours. For OS, no difference between capecitabine-containing and non-capecitabine-containing regimens was observed for all participants taken together (HR 1.01, 95% confidence interval (CI) 0.98 to 1.05; 12 studies, 4325 participants; high-certainty evidence), for those with hormone receptor-positive disease (HR 0.93, 95% CI 0.84 to 1.04; 7 studies, 1834 participants; high-certainty evidence), and for those with hormone receptor-negative disease (HR 1.00, 95% CI 0.88 to 1.13; 8 studies, 1577 participants; high-certainty evidence). For progression-free survival (PFS), a small improvement was seen for all people (HR 0.89, 95% CI 0.82 to 0.96; 12 studies, 4325 participants; moderate-certainty evidence). This was largely accounted for by a moderate improvement in PFS for inclusion of capecitabine in hormone receptor-positive cancers (HR 0.82, 95% CI 0.73 to 0.91; 7 studies, 1594 participants; moderate-certainty evidence) compared to no difference in PFS for hormone receptor-negative cancers (HR 0.96, 95% CI 0.83 to 1.10; 7 studies, 1122 participants; moderate-certainty evidence). Quality of life was assessed in five studies; in general there did not seem to be differences in global health scores between the two treatment groups at around two years' follow-up. Neoadjuvant studies were highly variable in design, having been undertaken to test various experimental regimens using pathological complete response (pCR) as a surrogate for disease-free survival (DFS) and OS. Across all patients, capecitabine-containing regimens resulted in little difference in pCR in comparison to non-capecitabine-containing regimens (odds ratio (OR) 1.12, 95% CI 0.94 to 1.33; 6 studies, 3152 participants; high-certainty evidence). By subtype, no difference in pCR was observed for either hormone receptor-positive (OR 1.22, 95% CI 0.76 to 1.95; 4 studies, 964 participants; moderate-certainty evidence) or hormone receptor-negative tumours (OR 1.28, 95% CI 0.61 to 2.66; 4 studies, 646 participants; moderate-certainty evidence). Four studies with 2460 people reported longer-term outcomes: these investigators detected no difference in either DFS (HR 1.02, 95% CI 0.86 to 1.21; high-certainty evidence) or OS (HR 0.97, 95% CI 0.77 to 1.23; high-certainty evidence). In the adjuvant setting, a modest improvement in OS was observed across all participants (HR 0.89, 95% CI 0.81 to 0.98; 8 studies, 13,547 participants; moderate-certainty evidence), and no difference in OS was seen in hormone receptor-positive cancers (HR 0.86, 95% CI 0.68 to 1.09; 3 studies, 3683 participants), whereas OS improved in hormone receptor-negative cancers (HR 0.72, 95% CI 0.59 to 0.89; 5 studies, 3432 participants). No difference in DFS or relapse-free survival (RFS) was observed across all participants (HR 0.93, 95% CI 0.86 to 1.01; 8 studies, 13,457 participants; moderate-certainty evidence). As was observed for OS, no difference in DFS/RFS was seen in hormone receptor-positive cancers (HR 1.03, 95% CI 0.91 to 1.17; 5 studies, 5604 participants; moderate-certainty evidence), and improvements in DFS/RFS with inclusion of capecitabine were observed for hormone receptor-negative cancers (HR 0.74, 95% CI 0.64 to 0.86; 7 studies, 3307 participants; moderate-certainty evidence). Adverse effects were reported across all three scenarios. When grade 3 or 4 febrile neutropenia was considered, no difference was seen for capecitabine compared to non-capecitabine regimens in neoadjuvant studies (OR 1.31, 95% CI 0.97 to 1.77; 4 studies, 2890 participants; moderate-certainty evidence), and a marked reduction was seen for capecitabine in adjuvant studies (OR 0.55, 95% CI 0.47 to 0.64; 5 studies, 8086 participants; moderate-certainty evidence). There was an increase in diarrhoea and hand-foot syndrome in neoadjuvant (diarrhoea: OR 1.95, 95% CI 1.32 to 2.89; 3 studies, 2686 participants; hand-foot syndrome: OR 6.77, 95% CI 4.89 to 9.38; 5 studies, 3021 participants; both moderate-certainty evidence) and adjuvant trials (diarrhoea: OR 2.46, 95% CI 2.01 to 3.01; hand-foot syndrome: OR 13.60, 95% CI 10.65 to 17.37; 8 studies, 11,207 participants; moderate-certainty evidence for both outcomes).

AUTHORS' CONCLUSIONS

In summary, a moderate PFS benefit by including capecitabine was seen only in hormone receptor-positive cancers in metastatic studies. No benefit of capecitabine for pCR was noted overall or in hormone receptor subgroups when included in neoadjuvant therapy. In contrast, the addition of capecitabine in the adjuvant setting led to improved outcomes for OS and DFS in hormone receptor-negative cancer. Future studies should stratify by hormone receptor and triple-negative breast cancer (TNBC) status to clarify the differential effects of capecitabine in these subgroups across all treatment scenarios, to optimally guide capecitabine inclusion.

Triple-negative and HER2-positive breast cancers found by mammography screening show excellent prognosis

PURPOSE

Our purpose was to explore the prognosis of aggressive breast cancers of the HER2 oncogene amplification (HER2 +) and triple-negative (TN) subtypes detected by screening, as well as the prognosis of interval cancers (clinically due to symptoms between screening rounds) and cancers in screening nonparticipants.

METHODS

The study population comprised of 823 breast cancers in women aged 50-69 years from 2006-2014. Of these, 572 were found by screening mammography (69%), 170 were diagnosed between the screening rounds (21%), and 81 were diagnosed in women who did not participate in the screening program (10%).

RESULTS

The majority of all HER2 + (59%) and TN cancers (57%) in this age group were detected by screening. Screen-detected HER2 + tumors were small (median 12 mm), and node-negative (84%). During a median follow-up of eight years, the distant disease-free survival of screen-detected HER2 + and TN cancers was better than that of interval and nonparticipant cancers (age-adjusted HR = 0.16, 95% CI 0.03-0.81 and HR = 0.09, 95% CI 0.01-0.79, respectively). In nonparticipants, the distant disease-free survival of these cancers was worse than in participants (age-adjusted HR = 2.52, 95% CI 0.63-10.11 and HR = 5.30, 95% 1.16-24.29, respectively).

CONCLUSION

In the 50-69 age group, the majority of HER2 + and TN cancers can be found by a quality assured population-based mammography screening. Despite their generally aggressive behavior, after a median follow-up of 8 years, distant disease-free survival was over 90% of these cancers detected by screening. The worst prognosis of these cancers was in women who did not participate in screening.

A review of current progress in triple-negative breast cancer therapy

Triple-negative breast cancer (TNBC) is a particularly aggressive subtype known for its extremely high drug resistance, progression, poor prognosis, and lack of clear therapeutic targets. Researchers are aiming to advance TNBC treatment worldwide. In the past 2–3 years, more positive results have emerged in the clinical research on TNBC treatment. Based on the results, several impressive drugs have been approved to benefit patients with TNBC, including the PARP inhibitors olaparib and talazoparib for germline BRCA mutation-associated breast cancer (gBRCAm-BC) and immunotherapy using the checkpoint inhibitor atezolizumab in combination with nab-paclitaxel for programmed cell death-ligand 1-positive (PD-L1+) advanced TNBC. Although neoadjuvant therapy has focused on combinations of systemic agents to optimize pathologically complete response, metastatic TNBC still has a poor prognosis. Innovative multidrug combination systemic therapies based on neoadjuvants and adjuvants have led to significant improvements in outcomes, particularly over the past decade.

Economic evaluation of adjuvant trastuzumab therapy for HER2-positive early-stage breast cancer: systematic review and quality assessment

INTRODUCTION

As the availability of new economic evaluations (EE) on adjuvant trastuzumab therapy for early-stage breast cancer (EBC) with HER2-positive since last search and other EEs missed warrant a more extensive review, this study aimed to systematically review EEs of adjuvant trastuzumab compared with chemotherapy alone for HER2-positive EBC.

AREA COVERED

The search was performed in February 2019 using MEDLINE and Scopus. Reviewers independently selected studies based on eligibility criteria, extracted data, assessed quality of reporting, and appraised quality of data sources.

EXPERT OPINION

22 studies were included which were from high-income (HICs) and upper-middle income countries (UMICs). Incremental cost-effectiveness ratios (ICERs) from HICs were within their cost-effectiveness thresholds and ranged from 6,018 to 78,929 USD per quality-adjusted life year (QALY) gained. ICERs from UMICs mostly exceeded their thresholds ranging from 3,526 to 174,901 USD per QALY gained. Evidence shows cost-effectiveness of trastuzumab for HER2-positive EBC in HICs. There were no methodological variations. The extent and adequacy of reporting were high. The quality of data sources was moderate to high. The quality of future EEs can be improved by enhancing the reporting quality, by using context-based data and real-world efficacy data, which would impact cost-effectiveness.

Predictive Biomarkers for Adjuvant Capecitabine Benefit in Early-Stage Triple-Negative Breast Cancer in the FinXX Clinical Trial

PURPOSE

Recent studies have demonstrated a benefit of adjuvant capecitabine in early breast cancer, particularly in patients with triple-negative breast cancer (TNBC). However, TNBC is heterogeneous and more precise predictive biomarkers are needed.

EXPERIMENTAL DESIGN

Tumor tissues collected from TNBC patients in the FinXX trial, randomized to adjuvant anthracycline-taxane-based chemotherapy with or without capecitabine, were analyzed using a 770-gene panel targeting multiple biological mechanisms and additional 30-custom genes related to capecitabine metabolism. Hypothesis-generating exploratory analyses were performed to assess biomarker expression in relation to treatment effect using the Cox regression model and interaction tests adjusted for multiplicity.

RESULTS

One hundred eleven TNBC samples were evaluable (57 without capecitabine and 54 with capecitabine). The median follow-up was 10.2 years. Multivariate analysis showed significant improvement in recurrence-free survival (RFS) favoring capecitabine in four biologically important genes and metagenes, including cytotoxic cells [hazard ratio (HR) = 0.38; 95% confidence intervals (CI), 0.16-0.86, P-interaction = 0.01], endothelial (HR = 0.67; 95% CI, 0.20-2.22, P-interaction = 0.02), mast cells (HR = 0.78; 95% CI, 0.49-1.27, P-interaction = 0.04), and PDL2 (HR = 0.31; 95% CI, 0.12-0.81, P-interaction = 0.03). Furthermore, we identified 38 single genes that were significantly associated with capecitabine benefit, and these were dominated by immune response pathway and enzymes involved in activating capecitabine to fluorouracil, including TYMP. However, these results were not significant when adjusted for multiple testing.

CONCLUSIONS

Genes and metagenes related to antitumor immunity, immune response, and capecitabine activation could identify TNBC patients who are more likely to benefit from adjuvant capecitabine. Given the reduced power to observe significant findings when correcting for multiplicity, our findings provide the basis for future hypothesis-testing validation studies on larger clinical trials.

Adjuvant addition of capecitabine to early-stage triple-negative breast cancer patients receiving standard chemotherapy: a meta-analysis

PURPOSE

Triple-negative breast cancer (TNBC) pertains to a breast cancer subtype that has the highest metastatic and recurrence rates. The effectiveness of capecitabine as adjuvant chemotherapy for TNBC has remained unclear. This study conducted a meta-analysis of the efficacy of capecitabine as adjuvant chemotherapy for early-stage TNBC treated with taxane-/anthracycline-based chemotherapy.

METHODS

We identified relevant research reports in online databases until May 2019. We finally included seven randomized clinical trials to perform this meta-analysis. Altogether, the seven trials enrolled 3151 early-stage TNBC patients, with 1552 receiving standard (neo)adjuvant chemotherapy regimens and 1599 receiving addition of capecitabine in the adjuvant settings besides standard regimens.

RESULTS

A meta-analysis of the seven trials revealed a significant increase in disease-free survival (DFS) with the addition of capecitabine (Hazard ratio (HR) = 0.77, 95% CI 0.66-0.90). This improvement in DFS was significant both in trials conducted in America-Europe and in Asia. In trials involving six to eight cycles of capecitabine addition, we observed a significant improvement in DFS. Furthermore, in the meta-analysis of six trials, we detected a significant increase in overall survival (OS) favoring capecitabine (HR = 0.69, 95% CI 0.56-0.85).

CONCLUSIONS

Adjuvant addition of capecitabine to early-stage TNBC patients receiving standard chemotherapy showed significant DFS and OS improvement. Future studies involving the selection of patients that may have the highest survival benefit from adding capecitabine are warranted.

Cost-utility analysis of adjuvant trastuzumab therapy for HER2-positive early-stage breast cancer in the Philippines

Background

Breast cancer is the leading malignancy among Filipino women, with about 23.50% of cases characterized by human epidermal growth factor receptor-2 (HER2) overexpression. Trastuzumab, in addition to standard chemotherapy, is currently recommended as primary treatment for HER2-positive early-stage breast cancer (EBC) in the adjuvant settings, and has been listed in the Philippine National Formulary (PNF) since 2008, but with no current evidence yet on its value for money, to date. Hence, despite several policy enablers, its accessibility remains to be limited in the Philippines. We performed an economic evaluation to assess the cost-effectiveness and budget impact of adjuvant trastuzumab therapy for HER2-positive EBC in the Philippines, using healthcare system and societal perspectives, in aid of guiding coverage decisions.

Methods

A Markov model-based cost-utility and budget impact analyses were conducted to estimate the total costs incurred and outcomes gained in using 1 year of adjuvant trastuzumab added to standard chemotherapy versus standard chemotherapy alone, over a lifetime horizon. We discounted both costs and outcomes at 3.5% per annum. Parameters were estimated using country survival data, systematic review and meta-analysis of the relative treatment effect, local and international cost data, and published utility data. Univariate and probabilistic sensitivity analyses were used to account for parameter uncertainty.

Results

Trastuzumab therapy was dominated with an incremental cost-effectiveness ratio (ICER) at PHP 453,505 per QALY gained from a healthcare system perspective or PHP 458,686 per QALY gained from a societal perspective, with 10% cost-effectiveness probability at the country cost-effectiveness threshold of PHP 120,000 per QALY gained. National implementation will cost an additional amount of PHP 13,909 million in year one alone, plus about PHP 2000 to 3000 million annually for the succeeding fiscal years.

Conclusion

At its current cost, 1 year of adjuvant trastuzumab therapy compared to standard chemotherapy alone for HER2-positive EBC does not represent value for money in the Philippines. Its current cost will have to significantly lower down by one-half to achieve cost-effectiveness.

Adjuvant trastuzumab regimen for HER2-positive early-stage breast cancer: a systematic review and meta-analysis

Objective: Breast cancer remains to be the globally leading female cancer. About 15% to 20% of breast cancers have human epidermal growth factor receptor 2 (HER2)-positive tumors - a more aggressive breast cancer subtype with shortened survival. In the light of new and updated trial data on trastuzumab therapy for HER2-positive early-stage breast cancer (EBC), we conducted a systematic review and meta-analysis to update the pooling of its relative treatment effects. Methods: Systematic search was performed through Pubmed and Scopus to identify studies comparing survival outcomes and risks of heart toxicity effects of adjuvant trastuzumab with chemotherapy versus chemotherapy alone for HER2-positive EBC patients. Results: Based on the eight included studies in the review, combining trastuzumab with chemotherapy continues to show lowered death and relapse risks by one-third. The decision to initiate trastuzumab, however, needs to be prudently deliberated as two to three times more cardiotoxicity risk was shown to be associated with its use. Conclusion: Administering adjuvant trastuzumab in a weekly cycle concurrently with anthracycline-taxane chemotherapy regimen appears to be a preferable option to optimize its favorable effect in improving DFS and to prevent significantly higher risk for cardiotoxic effects.

Herceptin® (trastuzumab) in HER2-positive early breast cancer: a systematic review and cumulative network meta-analysis

BACKGROUND

Originator trastuzumab (Herceptin®; H) is an antibody-targeted therapy to treat patients with human epidermal growth factor receptor 2-positive (HER2+) early breast cancer (EBC). We investigated the overall survival (OS) advantage conferred by the addition of H to chemotherapy for HER2+ EBC patients and how the OS advantage changed over time.

METHODS

A systematic literature review (SLR) identified randomized controlled trials (RCTs) and non-randomized studies (NRSs) published from January 1, 1990 to January 19, 2017, comparing systemic therapies used in the neoadjuvant/adjuvant settings to treat HER2+ EBC patients. Bayesian cumulative network meta-analyses (cNMAs) of OS were conducted to assess the published literature over time. Heterogeneity was assessed through sensitivity and subgroup analyses.

RESULTS

The SLR identified 31 unique studies (28 RCTs, 3 NRSs) included in the OS analyses from 2008 to 2016. In the reference case cNMA (RCTs alone), initial evidence demonstrated an OS advantage for H/chemotherapy compared with chemotherapy alone in HER2+ EBC patients. As additional OS data were published, the precision around this survival benefit strengthened over time. Both H/anthracycline-containing chemotherapy and H/non-anthracycline-containing chemotherapy regimens provided similar OS advantages for HER2+ EBC patients.

CONCLUSION

This analysis represents the most comprehensive SLR/cNMA to date of published OS data in HER2+ EBC studies. These findings demonstrate why H/chemotherapy is now the established standard of care in HER2+ EBC. In the case of H, the benefits of early patient access far outweighed the risk of waiting for more precise information.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42017055763.

Molecular subtypes of screen-detected breast cancer

BACKGROUND

Detection of breast cancers by mammographic screening confers a survival advantage of 20-50% compared to symptomatic presentations. The improved prognosis is only partly explained by stage migration. The distribution of the molecular subtypes of screen-detected breast cancer (SDBC) or their HER2 status has not been studied extensively. We wished to address these issues through the study of a large series of SDBC, with other presentations serving as controls.

DESIGN

Deidentified cases of female invasive cancer, diagnosed in Australia and New Zealand during 2005-2015, were retrieved from the BreastSurgANZ Quality Audit (BQA). Method of detection and selected patient, tumour and treatment data were assessed. Immunohistochemical surrogates for molecular subtypes were defined as Luminal A (ER+ and/or PR+, HER2-), Luminal B (ER+ and/or PR+, HER2+), HER2-enriched (ER-, PR- and HER2+) and basal-like (triple negative). Results were compared with the findings of controls and previous studies.

RESULT

100983 invasive cancers were diagnosed, including 32493 (32.7%) SDBC and 66907 (67.3%) with other presentations. The biomarker profile for SDBC versus other presentations in the same population was ER 89.3 versus 80.3%, PR 78.8 versus 69.8% and for HER2 11 versus 15.6%. The distribution of molecular subtypes was Luminal A 81.9 versus 70.74%, Luminal B 7.39 versus 9.52%, HER2-enriched 3.63 versus 6.06% and Basal-like 7.08 versus 13.68%. These differences were significant (p < 0.0001).

CONCLUSION

Molecular profiles of SDBC are significantly different from those of symptomatic cancers, with over-representation of the Luminal A and proportionately lower rates of all other subtypes. We have shown, for the first time, significantly lower rates of HER2 positivity in SDBC. These differences may contribute to the better survival of SDBC and have implications for prognostication, targeted therapy decisions and for laboratory quality assurance programs in setting target ranges for proportions of ER-positive and HER2 results in heavily screened populations.

Effectiveness of trastuzumab as adjuvant therapy in patients with early stage breast cancer: A systematic review and meta-analysis

Background: Trastuzumab in combination with chemotherapy has long been established as a standard treatment for HER2-positive patients in early stage breast cancer (BC). The present study aimed at assessing the effectiveness of trastuzumab adjuvant therapy in early stage BC in overall survival (OS) and disease-free survival (DFS). Methods: A systematic review and meta-analysis was performed to evaluate the effectiveness of trastuzumab adjuvant therapy. PubMed, Cochrane library, Scopus, Web of Science, and Embase databases were searched for relevant RCTs from the beginning to February 2017. Quality assessment of studies was conducted using the Cochrane Risk of Bias Tool. The desired outcomes were OS and DFS. Results: A total of 1818 articles were identified first, however, only 11 studies were eligible to be included in this study. Our findings and meta-analysis results revealed that trastuzumab is effective in increasing OS (OS hazard ratio: -0.286 ± 0.049, 95%CI (-0.381, - 0.191)) and improving DFS (DFS hazard ratio: -0.419± 0.077, 95%CI (-0.569, -0.269)). The most serious but negligible side effect of trastuzumab is congestive heart failure. Conclusion: Adding trastuzumab as adjuvant therapy in early stages of BC in HER2 positive patients could increase OS and DFS of the patients effectively.

BRAF, KRAS and PIK3CA Mutation and Sensitivity to Trastuzumab in Breast Cancer Cell Line Model

Studies show that approximately 20% of all breast cancer patients have a breast tumor that tests positive for Human Epidermal Growth Factor Receptor 2, otherwise known as the HER2 gene. As such, treatments for breast cancer usually include drugs that target HER2. The drug Trastuzumab is a recombinant antibody that has been approved by the FDA for the treatment of these HER2 positive breast cancers. However, researchers have found that mutations in associated genes, PIK3CA and KRAS, can cause the tumor to become resistant to Trastuzumab. The purpose of this article is to evaluate the sensitivity of the cancer cell lines to the drug Trastuzumab and investigate how this sensitivity is compromised by the PIK3CA, KRAS and BRAF gene mutations. Trastuzumab responsiveness was evaluated in breast cancer cell lines by treating the lines with an optimal concentration of the drug followed by a proliferation assay of the cell lines in the presence of monoclonal antibodies. We determined the optimum concentration of Trastuzumab to be 7 μg/well. The BRAF and KRAS mutated cell line, MDA-MB-231, showed the least sensitivity after being treated with trastuzumab when compared to the sensitivity of the PIK3CA mutated cell lines, MCF-7 and MDA-MB-361, and the KRAS/ BRAF/ PIK3CA cell line, MDA-MB-453. Clinical observations show that mutations in BRAF and KRAS genes in breast cancer cells do lower the responsiveness of Trastuzumab drug treatments.

Evaluation of Left Ventricular Ejection Fractions in Breast Cancer Patients Undergoing Long-Term Trastuzumab Treatment

Background

The aim of this study was to assess the long-term clinical tolerance and cardiac safety during trastuzumab treatment for patients diagnosed as having breast cancer with human epidermal growth factor receptor 2 (HER2) overexpression.

Material/Methods

A total 105 female cases diagnosed as having breast cancer with high expression of Her2, were treated with trastuzumab (T). All of them underwent electrocardiography monitoring in the process of T treatment. Left ventricular ejection fractions (LVEFs) were estimated using echocardiography before the T treatment and every 3 months. General clinical data and above parameters were collected and reviewed as analysis.

Results

The mean value of LVEFs with baseline was higher than those at other time points. All LVEFs were more than 50% during the course of trastuzumab treatment. The decline scope ≥15% of LVEFs ranged from 2 months to 16 months, and the ratios were counted for 3.1% at 2 months, 4.3% at 6 months, 3.8% at 10 months, and 5.4% at 16 months. Furthermore, a larger decrease of LVEF during the course occurred mainly in the patients with cumulative dose of A >300 mg/m², without CPD and 16-month duration of T treatment. There was a strong correlation between cumulative dose of A, cyto/cardio-protection drugs (CPD), duration of T, and the change of LVEF (P=0.82, P=0.744, and P=0.717, respectively), which indicated that 3 factors may be associated with the change in LVEF (P<0.05).

Conclusions

The LVEF in patients with trastuzumab treatment was significantly decreased, which may be seen as a favorable benefit-risk ratio for patients undergoing long-term trastuzumab treatment.

Adjuvant Chemotherapy and Trastuzumab Is Safe and Effective in Older Women With Small, Node-Negative, HER2-Positive Early-Stage Breast Cancer

INTRODUCTION

The benefit of adjuvant trastuzumab with chemotherapy is well established for women with higher risk human epidermal growth factor receptor 2-positive (HER2⁺) breast cancer. However, its role in older patients with smaller, node-negative tumors is less clear. We conducted a retrospective, sequential cohort study of this population to describe the impact of trastuzumab on breast cancer outcomes and cardiac safety.

PATIENTS AND METHODS

Women ≥ 55 years with ≤ 2 cm, node-negative, HER2⁺ breast cancer were identified and electronic medical records reviewed. A no-trastuzumab cohort of 116 women diagnosed between January 1, 1999 and May 14, 2004 and a trastuzumab cohort of 128 women diagnosed between May 16, 2006 and December 31, 2010 were identified. Overall survival and distant relapse-free survival were estimated by Kaplan-Meier methods.

RESULTS

The median ages of the trastuzumab and no-trastuzumab cohorts were 62 and 64 years, respectively. More patients in the trastuzumab cohort had grade III (P = .001), lymphovascular invasion (P = .001), or estrogen receptor-negative (P < .001) cancers. The majority of the trastuzumab cohort received chemotherapy versus one-half of the no-trastuzumab cohort (98% vs. 53%; P < .0001). The median follow-up was 4 versus 9 years in the trastuzumab versus no-trastuzumab cohorts; therefore, outcomes at 4 years are reported. Despite the higher-risk tumor features in the trastuzumab group, the 4-year overall survival was 99% in both cohorts; the distant relapse-free survival was 99% versus 97% in the trastuzumab versus no-trastuzumab cohorts. Four (3.1%; 95% confidence interval, 1.0%-7.8%) women in the trastuzumab cohort and 1 in the no-trastuzumab cohort developed symptomatic heart failure. There were no cardiac-related deaths in either arm.

CONCLUSION

Following adjuvant trastuzumab with chemotherapy, selected older women with small, node-negative, HER2⁺ breast cancers have excellent disease control. The rate of cardiac events is low.

Risk of Congestive Heart Failure in Early Breast Cancer Patients Undergoing Adjuvant Treatment With Trastuzumab: A Meta-Analysis

BACKGROUND

The use of trastuzumab has proven to be a successful strategy in patients with human epidermal growth factor receptor 2 (HER2)-positive breast cancer; however, it is associated with an increased risk of cardiac dysfunction. We performed an up-to-date, comprehensive meta-analysis to clarify the risk of congestive heart failure (CHF) in patients with early breast cancer receiving different durations of adjuvant trastuzumab with the longest-term follow-up.

METHODS

Eligible studies included randomized control trials of HER2-positive early breast cancer patients with or without trastuzumab in adjuvant chemotherapy. Adequate reporting of CHF data were required for inclusion. Statistical analyses were conducted to calculate the overall incidence, relative risk (RR), and 95% confidence interval (CI) by use of a fixed-effects model.

RESULTS

Six randomized control trials including 18,111 patients were identified. The overall incidence of high-grade CHF in patients treated with trastuzumab versus placebo was 1.44% (95% CI, 0.79%-2.64%) and the RR was 3.19 (95% CI, 2.03-5.02; p < .00001). In subgroup analysis, the difference in CHF incidence failed to achieve significance. The RR for 8 mg/kg trastuzumab (high dose) was greater than that for 4 mg/kg (low dose) (RR, 6.79, 95% CI, 2.03-22.72, p = .0001; versus RR, 2.64; 95% CI, 1.61-4.32; p = .002). Additionally, higher RRs were observed for patients receiving trastuzumab for 1 year (RR, 3.29; 95% CI, 2.07-5.25) and 2 years (RR, 9.54; 95%CI, 2.19-41.43), but not 9 weeks (RR, 0.50; 95% CI, 0.05-5.49) compared with control groups. No evidence of publication bias was observed.

CONCLUSION

Adjuvant trastuzumab therapy was strongly associated with an increased risk of significant CHF in patients with early breast cancer, particularly in 2-year use.

IMPLICATIONS FOR PRACTICE

This comprehensive meta-analysis evaluated the risk of congestive heart failure with a usage profile of adjuvant trastuzumab in patients with early breast cancer. Before initiating treatment with trastuzumab, a risk-benefit analysis for individual patients should be critically evaluated, considering that the prognosis is closely related to drug dose and duration of use. Cardiac function should be monitored throughout the treatment period and also during follow-up. Thus, early identification of trastuzumab-related cardiac dysfunction can allow effective medical intervention, elimination of symptoms, recovery of function, and continuation of trastuzumab therapy.

The clinical value of HER-2 overexpression and PIK3CA mutations in the older breast cancer population: a FOCUS study analysis

Studies to confirm the effect of acknowledged prognostic markers in older breast cancer patients are scarce. The aim of this study was to evaluate the prognostic value of HER-2 overexpression and PIK3CA mutations in older breast cancer patients. Female breast cancer patients aged 65 years or older, diagnosed between 1997 and 2004 in a geographical region in The Netherlands, with an invasive, non-metastatic tumour and tumour material available, were included in the study. The primary endpoint was relapse-free period and secondary endpoint was relative survival. Determinants were immunochemical HER-2 scores (0/1+, 2+ or 3+) and PIK3CA as a binary measure. Overall, 1698 patients were included, and 103 had a HER-2 score of 3+. HER-2 overexpression was associated with a higher recurrence risk (5 years recurrence risk 34 % vs. 12 %, adjusted p = 0.005), and a worse relative survival (10 years relative survival 48 % vs. 84 % for HER-2 negative; p = 0.004). PIK3CA mutations had no significant prognostic effect. We showed, in older breast cancer patients, that HER-2 overexpression was significantly associated with a worse outcome, but PIK3CA mutations had no prognostic effect. These results imply that older patients with HER-2 overexpressing breast cancer might benefit from additional targeted anti-HER-2 therapy.

Capecitabine in Combination with Standard (Neo)Adjuvant Regimens in Early Breast Cancer: Survival Outcome from a Meta-Analysis of Randomized Controlled Trials

Capecitabine has been investigated in early breast cancer in several studies, but it was undefined that whether it could improve survival. To investigate whether the addition of capecitabine affected survival in patients with early breast cancer, a meta-analysis was conducted and overall survival (OS), disease-free survival (DFS), and toxicity were assessed. The PubMed, Embase databases and the Cochrane Central Register of Controlled Trials were searched for studies between January 2006 and April 2016. Hazard ratios (HRs) with their 95% confidence intervals (CIs), or data for calculating HRs with 95% CI were derived. Seven trials with 9097 patients, consisted of 4 adjuvant and 3 neoadjuvant studies, were included in this meta-analysis. Adding capecitabine showed no improvement in DFS (HR = 0.93; 95% CI, 0.85-1.02; P = 0.12), whereas a significant improvement in OS was observed (HR = 0.85; 95% CI, 0.75-0.96; P = 0.008). A sub-analysis of DFS showed that benefit of capecitabine derived from patients with triple negative subtype and with extensive axillary involvement. Safety profiles were consistent with the known side-effects of capecitabine, but more patients discontinued scheduled treatment in the capecitabine group. Combining capecitabine with standard (neo)adjuvant regimens in early breast cancer demonstrated a significantly superior OS, and indicated DFS improvement in some subtypes with high risk of recurrence. Selection of subtypes was a key to identify patients who might gain survival benefit from capecitabine.

Cardiovascular toxicity associated with adjuvant trastuzumab therapy: prevalence, patient characteristics, and risk factors

Before the advent of the human epidermal growth factor receptor 2 (HER2)-targeted monoclonal antibody trastuzumab, HER2-positive breast cancers were difficult to treat and had a poor prognosis. Adjuvant trastuzumab is now an important part of the treatment regimen for many women with HER2-positive breast cancer and has undoubtedly resulted in a significant improvement in prognosis, but it is associated with a risk for cardiotoxicity. In this review, we describe the prevalence, patient characteristics, and risk factors for cardiotoxicity associated with use of adjuvant trastuzumab. Understanding risk factors for trastuzumab-induced cardiotoxicity and appropriate patient monitoring during trastuzumab treatment allows for safe and effective use of this important adjuvant therapy.