Anti-Leukemia Chemotherapy of High-Risk Myelodysplastic Syndromes.

We evaluated the outcome of anti-leukemia chemotherapy on 42 patients with the high-risk myelodysplastic syndromes (MDS)-refractory anemia with excess of blasts (RAEB), 8 cases; RAEB in transformation (RAEB-T), 18 cases; chronic myelomonocytic leukemia (CMMOL), 6 cases; and leukemic transformation of MDS, 10 cases. The median age was 67 (range 20 to 84). As a remission-induction therapy, 35 patients received low-dose chemotherapy, such as low-dose cytarabine infusion, and seven patients received high-dose combination chemotherapy. The complete remission (CR) rates of the low-dose chemotherapy group and the high-dose combination chemotherapy group were 29% and 57%, respectively, and the overall CR rate was 33%. The median survival durations after induction chemotherapy of the CR group (14 cases), the partial remission (PR) group (11 cases), and non-remission (NR) group (17 cases) were 19 months, 8 months, and 3 months, respectively. As a post-remission consolidation chemotherapy, high-dose combination chemotherapy seemed to be superior to low-dose chemotherapy judging from the median CR duration (16 months versus 4 months), but a long-term disease-free survival is hardly expected, in contrast with results in cases of de novo acute myeloid leukemia.