Twenty years' experience in allogeneic hematopoietic stem cell transplantation for Philadelphia chromosome-positive acute lymphoblastic leukemia in the Nagoya Blood and marrow transplantation group

Between October 1981 and December 2000, 46 patients with Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ ALL) underwent allogeneic hematopoietic stem cell transplantation (HSCT) in the Nagoya Blood and Marrow Transplantation Group. The median age was 28.5 years (range, 4-51 years). All but one patient achieved engraftment. Grade II-to-IV acute graft-versus-host disease (GVHD) developed in 32.5% of patients, and chronic GVHD developed in 40.5%. The incidences of relapse and treatment-related mortality (TRM) at 5 years were 65% and 26%, respectively. The estimated overall survival rate at 5 years was 23%. Univariate analysis showed that improved disease-free survival (DFS) was independently associated with complete remission (CR) at transplantation (39%), compared with non-CR (8%) (P = .023). Non-CR at transplantation was associated with a higher risk of relapse. Donor type, acute GVHD, and time from diagnosis to HSCT all had a significant effect on TRM. In a multivariate analysis, 9 months or more from diagnosis to HSCT was the only variable statistically significant for DFS (relative risk, 3.22; P = .01). This study demonstrates that allogeneic HSCT cures a significant population of patients with Ph+ ALL. Relapse is the major obstacle limiting the success of HSCT. Early transplantation during CR from donors, including unrelated persons or mismatched relatives, may offer improved long-term DFS.