Leukaemia is a major disease that seriously endangers human health, the long-term survival rate of acute myeloid leukaemia receiving conventional chemotherapy is only 10% to 45%, haematological relapse is the main cause of treatment failure in acute myeloid leukaemia, reducing the relapse rate is the key to improving the efficacy of acute leukaemia, biomarker-guided preemptive therapy is an effective way to reduce the recurrence of leukaemia, existing markers to predict the recurrence has a high false Existing markers have high false-negative and false-positive rates for predicting relapse, and improving the accuracy of leukaemia relapse prediction is a major clinical problem that needs to be solved urgently. The group has found that circulating leukaemia stem cells remaining after chemotherapy are the key to relapse, therefore, we propose to conduct a multicentre prospective clinical study on the prediction of acute leukaemia relapse by circulating leukaemia stem cells.

Inclusion Criteria:

• Newly diagnoses candidates with acute myeloid leukemia.
• Lower than or equal to 18 years-old;
• Subjects are able to provide written informed consent.

Exclusion Criteria:

• Subjects who cannot comply with the study;
• Subjects with severe cardiac disease (ejection fraction<50% ), liver disease (total bilirubin >34umol/L, ALT and AST>1.5×upper limit normal) or kidney disease (Serum creatinine>130umol/L).
• Subjects with severe infection.
• Subjects with other conditions that cannot receive chemotherapy or transplantation.

The study was an exploratory study in search of new biomarkers, based on the previous literature, the recurrence rates of pre-transplant MRD (+) and MRD (-) in pediatric AML were 41% and 23.8% respectively (Br J Haematol.2024;204:585-594), with the ratio of patients in the two groups being 1:1.The calculation was done using PASS 15.0 assuming a two-sided test of α=0.05 and a test efficacy of = 1-β=80%, with the number of people needed being 226, taking into account a 20% censoring rate, the final total sample size was 283 patients.