rituximab + doxorubicin + methotrexate + bleomycin + vincristine

A combination regimen consisting of the monoclonal antibody **rituximab** and the chemotherapy agents **doxorubicin**, **methotrexate**, **bleomycin**, and **vincristine**. Each component works through a distinct mechanism to target cancer cells: - **Rituximab** is a monoclonal antibody against CD20 on B cells, mediating B cell lysis via complement-dependent cytotoxicity, antibody-dependent cell-mediated cytotoxicity, and direct apoptosis induction. - **Doxorubicin** is an anthracycline antibiotic that intercalates DNA, inhibiting topoisomerase II and generating free radicals, leading to DNA damage and apoptosis. - **Methotrexate** is an antimetabolite and antifolate agent that inhibits dihydrofolate reductase, blocking DNA synthesis, repair, and cellular replication. - **Bleomycin** binds DNA and induces single- and double-strand breaks via free radical generation. - **Vincristine** is a vinca alkaloid that inhibits microtubule assembly, arresting cell division in metaphase. This precise five-drug combination is not a standard, named chemotherapy protocol but is composed of agents frequently found in regimens for aggressive lymphomas, such as MACOP-B and VACOP-B, to enhance cytotoxic efficacy in B-cell non-Hodgkin lymphoma and related malignancies[3][5].