Combination treatment may be valuable therapeutic option for HER2-negative metastatic breast cancer

Dec 1 2016

Finding the ideal combination of targeted, hormonal and chemotherapeutic agents to treat HER2-negative metastatic breast cancer has been challenging researchers for decades. In tumors which lack expression of the human epidermal growth factor receptor 2 (HER2-), the use of regimens based on the administration of paclitaxel, a taxane, and bevacizumab, a humanized monoclonal antibody directed against VEGF-A, eventually integrated by maintenance therapy with bevacizumab and/or endocrine therapy may represent a valuable therapeutic option. In other words, an initial round of targeted chemotherapy to rapidly halt cancer progression, followed by maintenance therapy to prevent further metastases. The specific drug regimen analyzed in a recent study resulted in better control of disease progression and a higher overall survival rate.

The study, "A Real-World Multicentre Retrospective Observational Study of Paclitaxel-Bevacizumab and Maintenance Therapy as First-Line Treatment for HER2-Negative Metastatic Breast Cancer," was recently published in the Journal of Cell Physiology an international, peer-reviewed journal focused on cancer-related issues.

Researchers identified 314 patients diagnosed with HER2-negative metastatic breast cancer at 12 Italian cancer centres. From that group, they identified a subgroup of about 180 hormone-receptor positive patients to administer maintenance endocrine therapy following paclitaxel discontinuation, which was eventually combined with bevacizumab maintenance therapy.

"Notwithstanding the overall improvement in the available therapeutic options, metastatic breast cancer is still considered incurable," says Dr. Maddalena Barba, researcher at the Regina Elena National Cancer Institute of Rome, Central Italy, "with particularly low survival rates in some patient subgroups for whom novel treatment combinations and potential therapeutic targets are urgently needed."

The authors belong to a multidisciplinary Italian-American team, which has long collaborated with Prof. Antonio Giordano, Director of the Sbarro Institute for Cancer Research, Temple University Philadelphia, USA.

"In this study, we observed evidence of the efficacy of first-line paclitaxel-bevacizumab in metastatic HER2 negative breast cancer patients. In addition, both bevacizumab and endocrine maintenance therapy significantly improved slowing disease progression and the overall survival rate, compared to cases with no maintenance therapies," says Dr Vici, clinical researcher at the division of Medical Oncology 2 of the Regina Elena National Cancer Institute.

"When addressing metastatic breast cancer, pathologists and oncologists work jointly to identify single therapeutic approaches to be used within a wider therapeutic strategy," says Prof. Antonio Giordano, a scientist with widely recognized expertise in breast cancer with a specific focus on translational research. "Each step of the decision making process is driven by specific disease features, such as the lack or presence of therapeutic important targets, which may be exemplified by HER2 and hormone receptors, along with our patients specific needs. In addition, data collected from real world populations, likewise those commonly involved in our research pipeline on breast cancer, are closer to the routine clinical practice and patient needs compared to the evidence from randomized clinical trials, whose participants are generally highly selected," Prof. Giordano concluded.