Objective: To explore the feasibility of HLA mismatched hemopietic stem cell transplants for the treatment of leukemia.
Methods: Between July 2000 and December 2001, seven patients received hemopietic stem cell transplants(HSCT) with HLA mismatched family donors, including 3 chronic myelocytic leukemia (CML), 3 acute nonlymphocytic leukemia (ANLL), and 1 acute lymphocytic leukemia (ALL). Stem cell sources were bone marrow(n = 1) or G-CSF mobilized peripheral blood (n = 6). All the patients were conditioned with busulfan (BU) 12 mg.kg-1 and cyclophosphamide (CY) 3.6 g.m-2, of whom 4 were conditioned with additioned antithymocyte globulin(ATG). Graft versus host disease (GVHD) prophylaxis regimen consisted of cyclosporin-A (CSA), methotrexate (MTX) and mycophenolate mofetil(MMF).
Results: One patients received 3.41 x 10(8) kg-1 mononuclear cells(MNC) from bone marrow; six patients received a mean number of 8.46 x 10(8) kg-1 (4.3 x 10(8)-15.4 x 10(8) kg-1) MNC from peripheral blood. The mean time of ANC > 0.5 x 10(9) L-1 was day 13 (11-16), and BPC > 20.0 x 10(9) L-1 was day 16 (11-23). All the patients got engraftment successfully and attained CR. Acute I-II GVHD occurred in 3(42.9%) patients, no acute III-IV GVHD occurred and extensive chronic GVHD did in 2(28.6%) patients. All the patients were alive and well after 6-24 months' follow-up.
Conclusion: (1) BU/CY plus ATG appears to be an effective conditioning regimen for HLA mismatched allogenic stem cell transplants. (2) G-CSF mobilized peripheral blood stem cells may be the source of stem cells even for HLA mismatched hemopietic stem cell transplants.