cyclophosphamide + doxorubicin + tamoxifen

This is a combination regimen consisting of three drugs—cyclophosphamide, doxorubicin, and tamoxifen—used primarily in the treatment of breast cancer. Cyclophosphamide is an alkylating agent that interferes with DNA replication and transcription, leading to cell death. Doxorubicin is an anthracycline antibiotic that intercalates into DNA, inhibits topoisomerase II, and generates free radicals to induce cytotoxicity. Tamoxifen is a selective estrogen receptor modulator (SERM) that acts as an antagonist on estrogen receptors in breast tissue, thereby inhibiting the growth of hormone-responsive tumors. This combination leverages both cytotoxic chemotherapy (cyclophosphamide and doxorubicin) and endocrine therapy (tamoxifen), providing a chemoendocrine approach for advanced or recurrent hormone receptor-positive breast cancer[1][5][6].