The purpose of this study is to collect clinical and laboratory data for patients affected by intermediate 1 and low risk Myelodysplastic Syndrome (MDS) associated by deletion 5q who were prescribed Revlimid from 31October 2008 to present. Revlimid is available in Italy for these patients since October 2008 based on a local disposition of the Italian Drug Agency (AIFA) issued according to a National law named 648/96.

There will be retrospective collection and integration of clinical laboratory data as well as prospective data collection on the same patients.

Inclusion Criteria:

• intermediate 1 and low risk MDS patients associated with:

  1. transfusion dependency anemia (at least 2 units per 8 weeks before starting of Revlimid treatment )

  2. 5q31-33 deletion isolated or associated to other chromosomal abnormalities.

     Exclusion Criteria:

• patients with serum creatinine > 2.5mg/dl

• child bearing potential females who do not use adequate contraceptive methods

Patients affected by intermediate-1 and low risk MDS associated by deletion 5q who were prescribed Revlimid from 31October 2008 to present.