[Therapeutic effect of ranimustine (MCNU) on essential thrombocythemia and polycythemia vera]

Seven patients with essential thrombocythemia and two patients with polycythemia vera were treated with ranimustine (MCNU). MCNU was given intravenously by drip infusion at a dose of 40-80 mg/m2 with intervals arranged in terns of the counts of both white blood cell and platelets. All cases with essential thrombocythemia obtained complete response, but the cases with polycythemia vera needed the combination of phlebotomy. The therapeutic effects were maintained for 2-5 months. No serious side effect was recognized except in two cases (22%) of mild nausea. Our study indicates that MCNU is useful for chemotherapy of chronic myeloproliferative disorders, especially, essential thrombocythemia.