Central Nervous System Relapse in Adults with Acute Lymphoblastic Leukemia after Allogeneic Hematopoietic Stem Cell Transplantation

摘要

Central nervous system (CNS) relapse after allogeneic hematopoietic stem cell transplantation (HSCT) confers a poor prognosis in adult patients with acute lymphoblastic leukemia (ALL). Preventing CNS relapse after HSCT remains a therapeutic challenge, and criteria for post-HSCT CNS prophylaxis have not been addressed. In a three-center retrospective analysis, we reviewed the data for 457 adult patients with ALL who received a first allogeneic HSCT in first or second complete remission (CR). All patients received CNS prophylaxis as part of their upfront therapy for ALL, but post transplant CNS prophylaxis practice varied by institution, and was administered to 48% of the patients. Eighteen patients (4%) developed CNS relapse after HSCT (isolated CNS relapse, n=8; combined bone marrow and CNS relapse, n=10). Patients with a prior history of CNS involvement with leukemia had a significantly higher rate for CNS relapse (P=0.002), and pre transplant CNS involvement was the only risk factor for post transplant CNS relapse found in this study. We failed to find a significant effect of post-transplant CNS prophylaxis to prevent relapse after transplant. Furthermore, no benefit for post-transplant CNS prophylaxis could be detected when a sub-group analysis of patients with (p=0.10) and without prior CNS involvement (p=0.52) was performed. Finally, we couldn’t find any significant impact for intensity of the transplant conditioning regimen on CNS relapse after HSCT. In conclusion, CNS relapse is an uncommon event following HSCT for ALL in CR1 or CR2, but with higher risk among patients with CNS involvement pre transplant. Furthermore, neither the use of post-HSCT CNS prophylaxis nor the intensity of the HSCT conditioning regimen made a significant difference in the rate of post-HSCT CNS relapse.