The incidence of MDS in the U.S. has been estimated at 3.4 cases per 100,000 people per year with the incidence increasing 10 fold in people over the age of 70. Risk factors for the development of MDS include advanced age, male sex, and prior exposure to DNA-damaging chemotherapy or radiation therapy, typically for treatment of other malignancies. As a group, patients with advanced MDS and those with MDS progressing to AML have treatment resistant disease with low response rates and short durations of response after induction therapy.