Donor cell myelodysplastic syndrome after allogeneic stem cell transplantation responding to donor lymphocyte infusion: case report and literature review.

Allogeneic hematopoietic stem cell transplantation (SCT) is a potentially curative treatment for patients with myelodysplastic syndrome (MDS). Relapses after transplantation however, are not uncommon and are usually due to re-emergence of a recipient derived, neoplastic, stem cell clone. We report a unique case of MDS recurring 5 months after non-myeloablative, sibling, allogeneic SCT. Interestingly, chimerism analysis at relapse showed hematopoiesis to be entirely of donor origin confirming donor cell MDS. Donor lymphocyte infusion (DLI) produced a hematological response lasting several months. Our review of the literature shows donor-derived MDS to be very rare, with only four such cases described previously. In this report, we describe the details of our case and discuss putative mechanisms underlying the genesis of donor cell MDS and the observed response to DLI.