Allogeneic Bone Marrow Transplantation for BCR-ABL Positive Acute Lymphoblastic Leukemia

The prognosis for patients with bcrabl positive acute lymphoblastic leukemia (ALL) treated with chemotherapy is extremely poor. Allogeneic bone marrow transplantation (BMT) may offer a curative option for patients who have appropriate donors available. Between 1984 and 1998,76 consecutive patients with bcr-abl positive ALL were treated with allogeneic BMT from HLA-matched donors: 26 patients in 1st complete remission (CR) with matched sibling donors (group A), 35 patients >lst CR with matched sibling donors (group B), and 15 patients (1st CR or more advanced) with matched related (MRD) or unrelated donors (MUD) (group C). The age range for all patients was from 3 to 56 years. Surviving patients have been followed for a median of four years. For patients in group A, the two-year probabilities of disease-free survival (DFS) and relapse are 68.6 % and 10.8 %, respectively. For patients transplanted after 1992, these probabilities are 81 % and 11% respectively. The relatively low relapse rate in this group of patients compared to published reports may reflect the enhanced anti-leukemic activity of etoposide in combination with FTBI compared to other conditioning regimens. The enhancement in overall survival for patients transplanted after 1992 may reflect improvements in supportive care, in particular, the prophylaxis of serious fungal and viral infections. For patients in Group B, the two-year probabilities for DFS and relapse are 36.7% and 38.2% respectively; and for Group C, the two-year probabilities for DFS and relapse are 6.7%and 59.4% respectively. Significant prognostic factors for DFS and risk of relapse include: disease status, allogeneic vs. MUD/MRD BMT, the occurrence of Grade II-IV acute GVHD, and the detection of pl90 bcr-abl post-BMT.