Clinical Effects of Unrelated-Donor or Related-Donor Hematopoietic Stem Cell Transplantation for Leukemia.

Patients and Methods: From February 2003 to May 2005, 118 patients with leukemia received URD-HSCT or RD-HSCT at our institution. 43 cases received URD-HSCT and 75 cases received RD-HSCT. The basic conditioning regimens were TBI (total-body irradiation) + CY (CTX) protocol or modified BuCY (hydroxyurea, busulfan, Ara-C and CTX) protocol. Fludarabine, cytosine arabinoside, etoposide and etc. were added to the basic conditioning regimens when treated patients with refractory leukemia or in NR. The 43 patients who were treated with URD-HSCT, included 43 patients matched at 6/6 HLA antigens based on conventional serologic typing methods, 11 at 5/6 HLA antigens, 1 at 4/6 HLA antigens and 1 at 3/6 HLA antigens. Among the 75 patients with RD-HSCT, 69 patients were matched at 6/6 HLA antigens serologically, 6 were matched at 5/6 HLA antigens. The basic protocol GVHD prophylaxis is CsA (cyclosporine) and methotrexate (MTX). Low-dose antithymocytes globulin (ATG) was added to the basic protocol when patients treated with URD-HSCT, and mycophenolate mofetil (MMF) and low-dose ATG added to the basic protocol were used in some patients with URD-HSCT.

Results and Conclusion: The patients treated with URD-HSCT or RD-HSCT have no significant differences in sex, age, disease type and pretransplantation condition. The overall survival was 57.5±0.83% and 58.7±10.5% in patients undergoing URD-HSCT and RD-HSCT, and the 3 year disease-free survival rate was 51.6±8.5% and 49.8±8.3%, respectively. The overall survival and 3 year disease-free survival differed little between unrelated and related transplantation(P>0.05). The relapse rate of leukemia between URD-HSCT and RD-HSCT were 9.3% and 18.8%, respectively, and significant difference was noted (P<0.05). II–IV° acute GVHD (aGVHD) occurred in 58.17% of the patients receiving URD- HSCT and in 33.00% of those with RD-HSCT, especially the incidence of III–IV° severe aGVHD in the two group was 16.0% and 9.0%, respectively, and there were significant differences, too. The mortality caused by GVHD in patients with URD-HSCT was 12.0% and that in RD-HSCT was 9.0%, and it differed little. The incidence of chronic GVHD (cGVHD) in patients who could be followed up after URD-HSCT was 51.15% and that in RD-HSCT was 53.85%, there was no significant difference. The mortality directly caused by infection in the two group was 7% and 4%, respectively, and there was no significant difference. Two patients with URD-HSCT died of venous occlusive disease (VOD), one hemorrhagic cystitis (HC) and one graft rejection, but there was no similar condition in RD-HSCT.