Median cfDNA levels did not statistically differ in terms of gender; primary diagnosis; extramedullary leukemia; cytogenetics, including fms like tyrosine kinase 3 (FLT3), nucleophosmin (NPM-1), AML1-ETO (RUNX1/RUX1T1), inv16 (CBFB/MYH11), and complex karyotype; pre-transplant disease status, development of mucositis; peri-engraftment infections; cytomegalovirus (CMV) reactivation; thrombotic microangiopathy (TMA); graft versus host disease (GvHD); and relapse (p>0.05). The gene discussed is FLT3; the disease is graft versus host disease.