Mitoxantrone is an anthraquinone antineoplastic agent with structural similarities to doxorubicin. It has a mechanism of action similar to the anthracyclines. Its primary elimination route is hepatic metabolism (only seven percent renal excretion) and it has a terminal half-life of -40 hours. Mitoxantrone has significant activity in the treatment of metastatic breast cancer, acute leukemias, and non-Hodgkin's lymphoma. Some activity is reported in head and neck cancer, Hodgkin's, myeloma, bladder cancer, prostate cancer, non-smallcell lung cancer, and liver cancer. There is a suggestion of incomplete cross-resistance between mitoxantrone and the anthracyclines in certain neoplasms. Some activity is reported with mitoxantrone in patients refractory to the anthracyclines in breast cancer, acute leukemias, and non-Hodgkin's lymphomas. The usual doses used in solid tumors and in lymphomas are mitoxantrone 12-14 mg/m' iv q3-4wk and in leukemias is mitoxantrone 12 mg/m'/d x 5 d iv for initial induction. Drug Inte/l Clin Pharm 1986;20:97-105.