Safety And Efficacy Of Azacitidine, and Lenalidomide In Higher Risk Myelodysplastic Syndrome

To evaluate the overall response rate of the combination of 5-azacitidine + Lenalidomide in high risk MDS patients (INT-2 and High risk defined by IPSS), and patients with low and int-1 who are considered to be at high risk due to unfavorable additional factors. * To evaluate the safety of the combination of 5-azacitidine + Lenalidomide in high risk MDS patients. * To evaluate the hematological improvement rate. * To evaluate the cytogenetic response rate. * To evaluate the Progression free survival (PFS). * To assess Quality of life.