Mobilization of PML-RARA negative blood stem cells and salvage with autologous peripheral blood stem cell transplantation in children with relapsed acute promyelocytic leukemia.

Background: Relapsed acute promyleocytic leukemia (APL) is treated with re-induction chemotherapy, commonly arsenic trioxide, and stem cell transplantation (SCT). The effect of arsenic trioxide on autologous peripheral blood stem cell collection is unknown.

Methods: Five pediatric patients with relapsed APL had PML-RARA negative peripheral blood stem cells mobilized (four after arsenic trioxide) and underwent autologous SCT after cyclophosphamide (60 mg/kg x 2) and total body irradiation (TBI-fractionated 1,200 cGy) conditioning.

Results: All five patients remain in molecular remission a median of 20 months post-transplant.

Conclusions: Autologous SCT performed during molecular remission is a treatment option for pediatric patients with relapsed APL and may provide durable leukemia-free survival without the complications of allogeneic transplantation.