STI 571 Combined with Hematopoetic Stem Cells Transplantation for Chronic Myeloid Leukemia.

Objective: to study the efficacy of STI 571 combined with allogenic hematopoietic stem cell transplantation (Allo-HSCT) or autologous peripheral blood stem cell transplantation (APBSCT) in chronic myeloid leukaemia (CML).

Methods: 18 CML patients were divided into 2 groups: group A (14) and group B (4). Patients in group A including 10 in CML accelerating phase or blast crisis phase, 4 in chronic phase. They all underwent Allo-HSCT and the median duration of STI 571 treatment before Allo-HSCT was 25 days (7–60d). 9 had related complete HLA-matched donors and 5 had unrelated complete matched donors, the preparation regimen was TBI+CTX +VP16 or BU/CY ±ATG, routine protocol was used to prevent graft versus host disease (GVHD). Patients of group B were all in chronic phase, the median duration of STI 571 treatment before APBSCT was 5.5 months (4–26d), and bcr/abl detected by FISH was continuously negative. Mobilization protocol was CAE + G-CSF, 3 of 4 underwent TBI+ CY+ VP16 followed by APBSCT.

Results: in group B, PBSC were separated after 5 days of mobilization, and (3.9–9.6)×10⁶/kg Cd34⁺ cells were obtained, however FISH- bcr/abl positive cells in separation products were higher than in bone marrow cells before separation (0.8% vs 2.8%). After a median follow up of 24 months (18–28 months), 2 cases relapsed, and one remains FISH-bcr/abl negative. In group A, 8 had GVHD, and after a median follow up of 8 months (4–20 months), 2 cases relapsed, 2 died of transplantation- related complications, 1 died of relapse, 9 remained disease free. Hematopoiesis was reconstituted in 8–21 days in patients of group A.

Conclusions: no obvious side effect was observed in STI 571 combined hematopoietic stem cell transplantation in CML patients.