Risk And Prognostic Factors Of CNS Leukemia After Allogenic Hematopoietic Stem Cell Transplantation In ALL Patients:A Case-control Study

Purpose:Central nervous system leukemia(CNSL)is the most common form of extramedullary relapse after hematopoietic stem cell transplantation(HSCT).This study aimed to explore the risk and prognostic factors for CNSL after HSCT,as well as the effects of post-HSCT prophylactic intrathecal injection on CNSL.Methods:From June 2013 to June 2016,105 patients with ALL underwent HSCT were selected.They were grouped into CNSL group and non-CNSL group according to whether they suffered CNSL post-HSCT.Different risk factors prior and post of HSCT were compared in the two groups.Results:With a mean follow-up of 16 months(range 2-43 mos),15 patients with CNSL post-HSCT were identified.The OS between the two groups were similar(77.9%vs 61.9%,p=0.189).Presence of CNSL prior to HSCT,non-CR at the time of HSCT,and matched related donor transplantation were the three main risk factors for CNSL post-HSCT.Damage during lumbar puncture did not increase the chance of CNSL post-HSCT.53.3%of the CNSL were isolated relapse.These patients had similar OS as those who did not relapse after HSCT(94.1%vs 87.5%,p=0.531).Conclusion:Presence of CNSL prior to HSCT,non-CR at the time of HSCT,and matched related donor transplantation were the three main risk factors for CNSL post-HSCT.Damage during lumbar puncture did not increase the chance of CNSL post-HSCT.Isolated CNS relapse had better prognosis than those with concurrent bone marrow relapse.