leucovorin + fluorouracil + irinotecan + oxaliplatin + panitumumab

**leucovorin + fluorouracil + irinotecan + oxaliplatin + panitumumab** is a multi-agent chemotherapy regimen used primarily in the treatment of advanced or metastatic colorectal cancer. - **Fluorouracil (5-FU)** is a pyrimidine analog that inhibits thymidylate synthase, interfering with DNA synthesis and function. - **Leucovorin** (folinic acid) is not cytotoxic itself but enhances the activity and cytotoxicity of 5-FU by stabilizing the binding of 5-FU’s active metabolite to thymidylate synthase. - **Irinotecan** is a topoisomerase I inhibitor that prevents DNA unwinding, leading to DNA damage and cell death. - **Oxaliplatin** forms DNA crosslinks, inhibiting DNA synthesis and transcription, resulting in cell death. - **Panitumumab** is a fully human monoclonal antibody that targets the epidermal growth factor receptor (EGFR), preventing ligand-induced activation and downstream signaling pathways involved in tumor proliferation and survival. This combination is typically indicated for patients with **KRAS/NRAS wild-type** metastatic colorectal cancer and is used in various sequences and combinations, often called “FOLFOXIRI plus panitumumab”. The regimen offers multi-modal activity: cytotoxic, DNA synthesis inhibition, and targeted anti-EGFR effects[2][4][6][7].