Clinical Outcome of Hematopoietic Stem Cell Transplantation for Philadelphia Chromosome-Positive Acute Lymphoblastic Leukemia (Ph + ALL): Experience From a Single Institution

Abstract

To identify factors affecting transplant outcome, data from 65 Philadelphia Chromosome-positive acute lymphoblastic leukemia (Ph + ALL) patients who had undergone allogeneic hematopoietic transplantation (allo-HSCT) in our institution were analyzed. The probability of OS (overall survival) and DFS (disease free-survival) at 3 years after allo-HSCT was 40.1% and 38%, respectively. Multivariate analysis showed that gender and disease status (p = 0.0059, p = 0.0039, respectively) were significant factors for OS. Among 51 patients with CR (complete remission), multivariate analysis showed that the factors associated with OS included gender (p = 0.014), number of white blood cell at diagnosis (p = 0.025), and the source of stem cells (bone marrow <BM > versus cord blood; BM stem cell source was associated with favorable OS, p = 0.042). Twenty-one patients relapsed after allo-HSCT with a median of 207 days (range, 19-1,324 days). The estimated cumulative incidence of relapse at 3 years was 39.4%. Patients with CR showed a lower relapse rate at 3 years (34.2%) when compared with patients with non-CR (62.7%). Among 21 patients, eight patients received imatinib-based chemotherapy and 13 received chemotherapy without imatinib before HSCT. In terms of treatment after relapse, seven patients received chemotherapy with imatinib and 13 received chemotherapy without imatinib. Five patients underwent a second HSCT. One patient survived, and 20 patients died. In this study, disease status at time of allo-HSCT had a significant impact on OS, DFS, and relapse. Imatinib administration given before allo-HSCT was not associated with favorable outcome. Second-generation tyrosine kinase inhibitors may be more suitable candidates for Ph + ALL before and after allo-HSCT.