cyclophosphamide + epirubicin + fluorouracil + paclitaxel + trastuzumab

This is a multi-agent chemotherapy and targeted therapy regimen composed of five drugs: - **Cyclophosphamide** (an alkylating agent) - **Epirubicin** (an anthracycline antibiotic) - **Fluorouracil** (a pyrimidine analog antimetabolite, also known as 5-FU) - **Paclitaxel** (a taxane class microtubule inhibitor) - **Trastuzumab** (a monoclonal antibody targeting HER2/neu) This combination is used primarily in the treatment of HER2-positive breast cancer, often in the adjuvant or neoadjuvant setting. The regimen combines cytotoxic chemotherapy agents with trastuzumab, which specifically targets tumors overexpressing the human epidermal growth factor receptor 2 (HER2). Trastuzumab binds to HER2 on cancer cells, inhibiting cell proliferation and mediating immune responses against tumor cells. The other agents disrupt DNA synthesis or mitosis through various mechanisms. The combination aims to maximize anti-tumor efficacy by attacking cancer cells via multiple pathways—DNA damage, inhibition of DNA synthesis, disruption of mitotic spindle formation, and targeted blockade of growth signaling.