[Salvaged allogeneic hematopoietic stem cell transplantation for refractory/recurrent acute myeloid leukemia]

To evaluate the efficacy of salvaged allogeneic hematopoietic stem cell transplantation (allo-HSCT) for refractory/recurrent acute myeloid leukemia (AML).

A total of 45 patients with refractory/recurrent AML were enrolled from September 2006 to April 2010. The median blasts in bone marrow (BM) were 36% (20% to 92%) before conditioning. The donors were identical siblings (6) or unrelated ones (9) or haploidentical family members (30). Conditioning regiments were individualized according to patients' status, the regimen with high-dose cytarabine plus BuCy/CY was mostly used (20). The patients with impaired organ function received above regimen except using fludarabine instead of cyclophosphamide (16). FLAG followed by reduced-intensified BuCy was employed for the recipients with more than 40% blasts in BM (6) to reduce leukemia burden. TBI/CY or TBI/Fludarabine was used for the recipients with extramedullary infiltration of leukemia or multidrug resistant leukemia. G-CSF, MTX, NVT, Vm26, Acla or Thaltipa was added into conditioning regiments according to leukemia character.

All but 2 patients attained durable engraftment. The incidence of grade II to IV aGVHD and cGVHD were 34%, 59.1%, respectively. With median follow-up 30 (0.5 - 57) months, the relapse rate was 29.2%. Twenty-nine of 45 (60.2%) patients remained in complete remission since salvaged HSCT. Three-years disease-free survival and overall survival were 60.2% and 62.6%, respectively.

Our results indicated that the combination of salvaged HSCT with prophylactic immunotherapy might be a promising modality for treatment of refractory/recurrent AML, even with high leukemia burden.