The graft-versus-leukemia effect of prophylactic donor lymphocyte infusions after allogeneic stem cell transplantation is equally effective in relapse prevention but safer compared to spontaneous graft-versus-host disease.

"Declarations Informed consent and Ethics approvalThis analysis was performed in accordance with the declaration of Helsinki. All patients had given written informed consent to treatment, data analysis and publication prior to alloSCT. Additionally, every eligible patient was asked independently for informed consent prior to proDLI. Evaluation was approved by the ethics committee of Hannover Medical School (10263_BO_K_2022). Potential conflicts of interestThe authors have no financial or non-financial conflicts of interest to declare that are relevant to the content of this article. No funds, grants, or other support was received. Potential conflicts of interest The authors have no financial or non-financial conflicts of interest to declare that are relevant to the content of this article. No funds, grants, or other support was received."

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