Combinational treatments for breast cancer

Heterogenicity is an indispensable element of breast cancer, which manifests itself on clinical, histopathological, and molecular levels. This heterogenicity could be a determinant factor of disease progression and drug resistance in the patients. Common therapies for metastatic breast cancer include surgery, radiotherapy, chemotherapy, and immunotherapy. On the introduction of biologic medicine, target therapy, and gene therapy, a potential has been reached to lower the rate of morbidity and mortality and also to improve the quality of life among patients with breast cancer. Although these treatments have been frequently proved by yielding promising results, a very few number of them have found their way into clinic settings due to progressive nature of these tumors, diversity of cancer populations and their microenvironments, genetic instability, and heterogenicity of breast cancers. As only minor advancements have been made in the case of recurrent metastatic breast cancer, handling this condition is now considered a medical necessity. According to genetic instability and heterogenicity of breast tumors, it is implausible to assume a single-targeted therapy could help treating most solid tumors. So, this review aimed to put together studies focused on combinational treatments targeting growth inhibition and apoptosis induction in breast cancer cells and comparing the results with monotherapies.