EWOG-MDS SCT RC RIC 06

Patients with MDS of the subtype of refractory cytopenia (RC) are also enrolled in study EWOG-MDS RC 06, which evaluates the implications of oligoclonality of T-cell subtypes and PNH clones. RC patients with hypocellular bone marrow (BM) and normal karoytpye who proceed to hematopoietic stem cell transplantation (SCT) with reduced intensity conditioning (RIC) will also eligible for study EWOG-MDS SCT RC RIC 06.

The primary objectives of the study EWOG-MDS SCT RC RIC 06 are:

• To study hematopoietic chimerism in whole blood and different cell population (CD14, CD15, CD 56, CD3, CD19) as well as in dendritic cells and regulatory T-cells after SCT with RIC in patients with RC
• To compare the results of chimerism obtained with standard STR PCR (sensitivity 1%) with those obtained with SNP PCR (sensitivity 0.1- 0.01%)

The secodary objectives of the study are:

• To evaluate the relationship between mixed chimerism and hematological engraftment, OS and EFS
• To study the impact of mixed chimerism in plasmacytoid dendritic and regulatory T-cells on the incidence of acute and chronic GVHD