Myelodysplastic syndrome overview

Myelodysplastic syndrome (MDS) is a heterogeneous hematopoietic stem cell disorder characterized by bone marrow dysplasia and peripheral cytopenias. Eighty percent of patients found to have MDS are older than 60 years and therefore not eligible for the only potentially curative therapy, bone marrow transplantation. Currently, there is no standard for treating MDS; therapies range from supportive care with transfusions or hematopoietic growth factors and low-intensity cytarabine therapy, to intensive anti-acute myeloid leukemia-type chemotherapy. Some of these treatments induce a limited hematologic response, but none consistently extends survival. Many are highly toxic. More than half of patients with MDS die within 3 to 4 years of infections, bleeding complications, or progression to acute leukemia. Agents in development for MDS include all-trans retinoic acid (ATRA), decitabine, and thalidomide. Farnesyltransferase inhibitors modulate many of the cancer-signaling pathways implicated in MDS initiation or progression and may therefore be well suited for treatment of these biologically diverse hematologic malignancies. Phase I and II clinical studies in our center show that the oral FTI ZARNESTRA (formerly R115777, Ortho Biotech Oncology, Raritan, NJ) has promising anti-MDS activity, suggesting that further investigation of this agent and of this class in MDS is warranted.