Neoadjuvant therapy of early stage human epidermal growth factor receptor 2 positive breast cancer: latest evidence and clinical implications

A phase 2 trial of neoadjuvant metformin in combination with trastuzumab and chemotherapy in women with early HER2-positive breast cancer: the METTEN study

The METTEN study assessed the efficacy, tolerability, and safety of adding metformin to neoadjuvant chemotherapy plus trastuzumab in early HER2-positive breast cancer (BC). Women with primary, non-metastatic HER2-positive BC were randomized (1:1) to receive metformin (850 mg twice-daily) for 24 weeks concurrently with 12 cycles of weekly paclitaxel plus trastuzumab, followed by four cycles of 3-weekly FE75C plus trastuzumab (arm A), or equivalent regimen without metformin (arm B), followed by surgery. Primary endpoint was the rate of pathological complete response (pCR) in the per-protocol efficacy population. pCR rate was numerically higher in the metformin-containing arm A (19 of 29 patients [65.5%, 95% CI: 47.3-80.1]) than in arm B (17 of 29 patients [58.6%, 95% CI: 40.7-74.5]; OR 1.34 [95% CI: 0.46-3.89], P = 0.589). The rate of breast-conserving surgery was 79.3% and 58.6% in arm A and B (P = 0.089), respectively. Blood metformin concentrations (6.2 μmol/L, 95% CI: 3.6-8.8) were within the therapeutic range. Seventy-six percent of patients completed the metformin-containing regimen; 13% of patients in arm A dropped out because of metformin-related gastrointestinal symptoms. The most common adverse events (AEs) of grade ≥3 were neutropenia in both arms and diarrhea in arm A. None of the serious AEs was deemed to be metformin-related. Addition of anti-diabetic doses of metformin to a complex neoadjuvant regimen was well tolerated and safe. Because the study was underpowered relative to its primary endpoint, the efficacy data should be interpreted with caution.

Optimal treatment of early stage HER2-positive breast cancer

Significant advances have occurred in the treatment of human epidermal growth factor receptor 2 (HER2)-positive breast cancer that have changed its natural history. The addition of trastuzumab to standard therapy has dramatically improved the prognosis for patients with early stage, HER2-positive breast cancer to unprecedented survival outcomes. Yet, long-term follow-up data from adjuvant pivotal trials indicate that 15-24% of patients still develop recurrent disease. Most of the research has focused on the addition of novel anti-HER2 drugs to standard therapy, including studies evaluating the monoclonal antibody pertuzumab; the antibody-drug conjugate trastuzumab-emtansine (T-DM1); the selective, reversible HER2/epidermal growth factor receptor kinase inhibitor lapatinib; or the irreversible pan-HER2 inhibitor neratinib. Dual HER2 blockade has improved overall survival remarkably in metastatic breast cancer; however, in patients with early stage disease, it has led to small benefits in progression-free survival. Moreover, biologic heterogeneity within HER2-positive disease may determine response to treatment and prognosis. Different subgroups of patients with HER2-positive breast cancer may benefit from different therapeutic approaches. Thus, there is ongoing work to optimize and de-escalate treatment in patients who may do just as well with less therapy and can avoid unnecessary treatments and their related toxicities. The objective of this review is to summarize the background and latest evidence on the current management of early stage, HER2-positive breast cancer and to present novel perspectives on its management.

Annexin A1 in inflammation and breast cancer: a new axis in the tumor microenvironment

Targeting inflammation in cancer has shown promise to improve and complement current therapies. The tumor microenvironment plays an important role in cancer growth and metastasis and -tumor associated macrophages possess pro-tumoral and pro-metastatic properties. Annexin A1 (ANXA1) is an immune-modulating protein with diverse functions in the immune system and in cancer. In breast cancer, high ANXA1 expression leads to poor prognosis and increased metastasis. Here, we will review ANXA1 as a modulator of inflammation, and discuss its importance in breast cancer and highlight its new role in alternative macrophage activation in the tumor microenvironment. This review may provide an updated understanding into the various roles of ANXA1 which may enable future therapeutic developments for the treatment of breast cancer.

Use of trastuzumab as an adjuvant/neoadjuvant therapy in patients with HER2-positive breast cancer in China: The Nvwa study

The aim of this study was to understand current trends in trastuzumab use in China as a neoadjuvant/adjuvant therapy for human epidermal growth factor receptor-2 positive (HER2+) breast cancer and identify factors influencing trastuzumab use.This was a retrospective, multicenter, cross-sectional study of patients diagnosed with HER2+ breast cancer (stage I-III), between July 2013 and June 2014, at 155 hospitals in 29 provinces/cities in China. Demographic and clinical data, including tumor characteristics and details of adjuvant/neoadjuvant therapies used, were collected. Data analysis included univariate analysis, multivariate logistic regression, and subgroup analyses.Of 4994 HER2+ patients (mean age 51.1 ± 9.9 years) included, only 29.8% received trastuzumab, with 30.5% in adjuvant therapy and 18.3% in neoadjuvant therapy. The highest rates of adjuvant trastuzumab were in Beijing (59.3%), Jiangsu (57.1%), and Ningxia (50.0%), while those of neoadjuvant trastuzumab were in Guangdong (24.8%), Beijing (14.1%), and Zhejiang (10.7%). Multivariate regression results revealed that factors associated with trastuzumab use were medical insurance cover for trastuzumab, residing locally to the hospital, more lymph node involvement, and more advanced tumor stage. Subgroup analysis revealed that patients receiving neoadjuvant therapy were likely to be younger, premenopausal and non-local, and had lymph node metastases, more advanced tumor, and progesterone receptor positive tumor.Trastuzumab use in patients with HER2+ breast cancer is relatively low in China, especially for neoadjuvant therapy. Insurance coverage seems to be the most correlated factor that influences the use of trastuzumab in Chinese patients with HER2+ breast cancer.

On baseball and breast cancer

Dedicated to the memory of Dr. William Hunter Harridge and Nonie Lowry, this manuscript discusses the ups and downs associated with novel therapies in breast cancer, and applies the lessons of persistence learned from baseball to our quest for more optimal treatments, particularly in triple negative breast cancer.

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.

Predicting and Overcoming Chemotherapeutic Resistance in Breast Cancer

Our understanding of breast cancer and its therapeutic approach has improved greatly due to the advancement of molecular biology in recent years. Clinically, breast cancers are characterized into three basic types based on their immunohistochemical properties. They are triple-negative breast cancer, estrogen receptor (ER) and progesterone receptor (PR)-positive-HR positive breast cancer, and human epidermal growth factor receptor 2 (HER2)-positive breast cancer. Even though these subtypes have been characterized, assessment of a breast cancer's receptor status is still widely used to determine whether or not a targeted therapy could be applied. Moreover, drug resistance is common in all breast cancer types despite the different treatment modalities applied. The development of resistance to different therapeutics is not mutually exclusive. It seems that tumor could be resistant to multiple treatment strategies, such as being both chemoresistant and monoclonal antibody resistant. However, the underlying mechanisms are complicated and need further investigation. In this chapter, we aim to provide a brief review of the different types of breast cancer and their respective treatment strategies. We also review the possible mechanisms of potential drug resistance associated with each treatment type. We believe that a better understanding of the drug resistance mechanisms can lead to a more effective and efficient therapeutic success.

BMI and Pathologic Complete Response to Neoadjuvant Chemotherapy in Breast Cancer: A Study and Meta-Analysis

INTRODUCTION

There is only limited data from clinical practice on the relevance of body mass index (BMI) on pathologic complete response (pCR) following neoadjuvant chemotherapy (NAC) in patients with breast cancer (BC).

PATIENTS AND METHODS

The impact of BMI on pCR and survival outcome was examined in 324 patients with primary non-metastatic BC. An additional meta-analysis was performed on the current data and relevant previously published studies in clinical practice.

RESULTS

Multivariable regression analysis identified lymph vascular invasion (odds ratio [OR], 0.05; 95% confidence interval [CI], 0.01-0.18; P = .0000), grading 3 (OR, 3.12; 95% CI, 1.59-6.12; P = .0009), and HER2/neu status (OR, 4.76; 95% CI, 1.86-12.18; P = .011) as independent factors for pCR after NAC. There was no association between pCR and continuous or categorical BMI. Various additional subgroup analyses of molecular BC subtypes (triple-negative, luminal-like, HER2-luminal, HER2-like) and BMI also showed no association. These findings were confirmed by the meta-analysis. Except for one subgroup analysis in which overweight and obese patients were combined as one group, no association between BMI and pCR as well as survival outcome was found.

CONCLUSIONS

BMI was not established as a relevant clinical factor. Only lymph vascular invasion, grading 3, luminal-like, and HER2/like BC subtype showed predictive and prognostic impact in patients with BC receiving NAC.

Trastuzumab, non-pegylated liposomal-encapsulated doxorubicin and paclitaxel in the neoadjuvant setting of HER-2 positive breast cancer

BACKGROUD

Neoadjuvant treatment based on the combination of trastuzumab plus chemotherapy is the standard of care in patients with HER2-positive early or locally advanced breast cancer. The concurrent use of trastuzumab, anthracyclines and taxanes is frequently used in this setting despite the potential cardiotoxicity of both anthracyclines and trastuzumab. However, not much information is available about this chemotherapy scheme.

OBJECTIVE

We wanted to evaluate the efficacy and safety profile of the combination of trastuzumab, liposome-encapsulated doxorubicin and paclitaxel as neoadjuvant scheme. We also tried to establish predictive factors of pathologic complete response.

SETTING

The study was carried out in a tertiary University Hospital of Spain.

METHOD

This is a descriptive study of the clinical practice performed in our hospital.

MAIN OUTCOME MEASURE

Efficacy was measured in terms of pathologic complete response, which was defined as the absence of invasive cancer cells in the breast and the axilla after neoadjuvant treatment.

RESULTS

Thirty patients were included, the median age was 48. Seventeen (56.7 %) were hormonal receptor (HR) positive, 14 (46.6 %) had IIIa-b clinical stage and one of them had inflammatory breast cancer. 12 patients (40 %) achieved pCR. Patients with HR-negative BC achieved a higher pCR rate than those ones with HR-positive BC (61.5 % and 23.5 %, respectively; p value = 0.035). 21 patients (70 %) underwent breast conservative surgery. The treatment was in general well tolerated, most frequent grade 3-4 adverse events were neutropenia (20 %), asthenia and liver enzyme alteration (10 %) and febrile neutropenia (6.7 %). No patient developed heart failure, but one (3.3 %) presented a 10 % asymptomatic absolute reduction in left ventricular fraction ejection.

CONCLUSIONS

The studied treatment for the neoadjuvant setting of HER2 positive breast cancer seems to be an effective therapeutic option. Despite the expected high rate of cardiotoxicity of this regimen, the study results shows that this treatment regimen appears to be safe. The combination of trastuzumab, non-pegylated liposomal-encapsulated doxorubicin and paclitaxel should be considered for the treatment of HER2-overexpressing breast cancer.

Neoadjuvant endocrine treatment in early breast cancer: An overlooked alternative?

During the last decade neoadjuvant endocrine therapy (NET) has moved from being reserved for elderly and frail non-chemotherapy candidates to a primary systemic modality in selected patients with hormone sensitive breast cancer. Neoadjuvant hormonal treatment in patients with hormone receptor positive, HER-2 negative early breast cancer is proven to be an effective and safe option; it is associated with a higher rate of breast conserving surgery (BCS), may reduce the need for adjuvant chemotherapy and enables a delay of surgery for medical or practical reasons. Clinical responses range from 13% to 100% with at least 3 months of NET. Methods of assessing response should include MRI of the breast, particularly in lobular tumours. In studies comparing tamoxifen with aromatase inhibitors (AI), AI proved to be superior in terms of tumour response and rates of BCS. Change in Ki67 is accepted as a validated endpoint for comparing endocrine neoadjuvant agents. Levels of Ki67 during treatment are more closely related to long-term prognosis than pretreatment Ki67. Neoadjuvant endocrine therapy provides a unique opportunity for studies of endocrine responsiveness and the development of new experimental drugs combined with systemic hormonal treatment.

Monitoring Trastuzumab Resistance and Cardiotoxicity: A Tale of Personalized Medicine

While approval of trastuzumab, a recombinant monoclonal antibody directed against HER2, along with a diagnostic kit to detect breast cancers which are positive for HER2 overexpression, has advanced a new era of stratified and personalized medicine, it also created several challenges to our scientific and clinical practice. These problems include trastuzumab resistance and trastuzumab-induced cardiotoxicity. In this review, we will summarize data from the literature regarding mechanisms of trastuzumab resistance and trastuzumab-induced cardiotoxicity and present some promising model systems that may advance our understanding of these mechanisms. Our discussion will include development of circulating tumor cells and circulating tumor DNA for monitoring tumor burden, of patient-derived xenograft models for preclinical testing of novel therapies, and of novel therapeutic strategies for trastuzumab-resistance and possible integration of these strategies in the design of co-clinical studies for testing in relevant patient subpopulations.