Pseudo-autologous stem cell transplantation for donor-derived mantle cell lymphoma 12 years after allogeneic transplantation.

Donor-derived malignancy is a rare morbidity after allogeneic hematopoietic stem cell transplantation (HSCT), in which most previous cases have presented as acute leukemia or myelodysplastic syndrome. There have, however, been very few reports of donor-derived lymphoma. Here, we present a case of donor-derived mantle cell lymphoma 12 years after allogeneic HSCT, which was successfully treated with chemotherapy followed by pseudo-autologous HSCT (pASCT), i.e., an autologous HSC transplant following allogeneic HSCT in which the infused stem cell is considered to be derived from the donor cells. Although pASCT carries the risk of graft-versus-host disease (GVHD) due to the reinfusion of donor-derived peripheral blood cells, the present case did not develop GVHD without prophylaxis. The current case and a small number of previous reports suggest that the duration between allogeneic HSCT and pASCT may be important to the induction of immune tolerance, but further study in a larger number of cases is needed.