Assess the cumulative incidence of severe (III-IV) aGVHD after low-dose cyclophosphamide or CNI is used to after gDLI. Evaluate the overall survival rate (OS), non recurrent mortality rate (NRM), and recurrence rate (CIR) of two groups of patients; The complete response rate (CR) and partial response rate (PR) of patients with morphological/extramedullary recurrence, as well as the complete response rate and MRD response rate of patients with molecular recurrence. The incidence of adverse events such as infection, hemorrhagic cystitis, and cardiac events in two groups.

Assess the cumulative incidence of severe (III-IV) aGVHD after low-dose cyclophosphamide or CNI is used to after gDLI. Evaluate the overall survival rate (OS), non recurrent mortality rate (NRM), and recurrence rate (CIR) of two groups of patients; The complete response rate (CR) and partial response rate (PR) of patients with morphological/extramedullary recurrence, as well as the complete response rate and MRD response rate of patients with molecular recurrence. The incidence of adverse events such as infection, hemorrhagic cystitis, and cardiac events in two groups.

Efficacy Evaluation: Follow up observation of the difference in efficacy and safety between two groups in preventing severe (III-IV) aGVHD.

Primary Exploratory Endpoint: Assess the cumulative incidence of severe (III-IV) aGVHD after low-dose cyclophosphamide or CNI is used after gDLI.

Secondary Exploratory Endpoints:

1. 1-year overall survival rate (OS);
2. 1-year recurrence rate (CIR);
3. 1-year non recurrent mortality rate (NRM);
4. The complete response rate (CR) and partial response rate (PR) of patients with morphological/extramedullary recurrence, as well as the complete response rate and MRD response rate of patients with molecular recurrent minimal residual disease (MRD);
5. The incidence of adverse events such as infection, hemorrhagic cystitis, and cardiac events in two groups.

Inclusion Criteria:

• Subjects eligible for inclusion in this study must meet all of the following criteria:

  1. Patients with malignant hematological diseases undergo haploid/sibling incomplete matching/unrelated donor transplantation;
  2. Recurrence after transplantation (morphological, extramedullary, or molecular recurrence);
  3. Plan to administer granulocyte colony-stimulating factor mobilization donor lymphocyte infusion (gDLI) for treatment;
  4. No age, gender, or race restrictions;
  5. The physical condition assessment (ECOG-PS) of the Eastern Oncology Collaborative Group is 0-2 points;
  6. The patient or their authorized representative agrees to participate in the clinical trial and signs an informed consent form.

Exclusion Criteria:

• Subjects meeting any of the following criteria are not eligible for inclusion in this study:

  1. Siblings of matched donor transplant;

  2. Patients with other malignant tumors that require treatment;

  3. There are active infections, such as hepatitis B, hepatitis C, tuberculosis, etc;

  4. HIV serological reaction was positive;

  5. Suffering from mental illness or other conditions that cannot comply with research, treatment, and monitoring requirements;

  6. Pregnant patients or patients who are unable to take appropriate contraceptive measures during treatment;

  7. Active heart disease is defined as one or more of the following:

     1. Have a history of uncontrolled or symptomatic angina pectoris;
     2. Myocardial infarction less than 6 months prior to enrollment in the study;
     3. A history of arrhythmia requiring medication treatment or severe clinical symptoms;
     4. Uncontrolled or symptomatic congestive heart failure (>NYHA level 2);
     5. The ejection fraction is below the lower limit of the normal range.

  8. Individuals who are allergic to any medication or component such as Cy, CNI, etc;

  9. The researchers believe that it is not suitable for participants.