Used in chemotherapy to treat various cancers, particularly breast cancer, epirubicin hydrochloride works by interfering with DNA replication in cancer cells. It is effective in both early-stage and advanced cancer treatment, often combined with other chemotherapeutic agents. Commonly administered intravenously, it helps reduce tumor size before surgery or control cancer progression when surgery isn't possible. Its use is associated with manageable side effects compared to similar drugs, making it a preferred option in certain treatment regimens.