A Retrospective Study on the Relationship Between Donor Leukocyte Telomere Length and Prognosis of Acute Leukemia Patients Treated With Allogeneic Hematopoietic Stem Cell Transplantation

Study Overview
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Brief Summary
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This post hoc analysis included patients with acute leukemia who underwent allo-HSCT at the First Affiliated Hospital of Zhejiang University School of Medicine and Ruijin Hospital Shanghai Jiaotong University School of Medicine. Patients and their donors were assessed for eligibility to join this study. The inclusion criteria were: (1) age ≥ 5 years; (2) diagnosis of acute leukemia including acute myeloid leukemia, acute lymphocytic leukemia, and mixed phenotype acute leukemia; (3) patients attained complete remission (CR) and achieved full engraftment with 100% donor chimerism following allo-HSCT; (4) telomere testing was conducted on peripheral leukocytes of donors before granulocyte colony-stimulating factor (G-CSF) mobilization, and the results were obtained. Written informed consent was obtained from all included patients and their donors, and the study was conducted in compliance with the Declaration of Helsinki. Ethical approval was approved by the ethics review committee of the First Affiliated Hospital of Zhejiang University School of Medicine.

Official Title
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The First Affiliated Hospital, Zhejiang University School of Medicine

Conditions
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Acute Leukemia

Intervention / Treatment
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* Other: No intervention, observation study


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age ≥ 5 years First allo-HSCT from matched related, unrelated, or haploidentical donors Achievement of complete remission after allo-HSCT Donor blood sample collection before granulocyte colony-stimulating factor mobilization Exclusion Criteria Non-acute leukemia diagnoses, including acute myeloid leukemia, acute lymphocytic leukemia, and mixed phenotype acute leukemia Failure to achieve engraftment with full donor chimerism after allo-HSCT Inability to extract DNA for telomere length analysis.

Ages Eligible for Study
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Minimum Age: 5 Years
Maximum Age: 90 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Donors aged 40 years or older<br> | Other: No intervention, observation study<br>* No intervention, observation study<br>|
| Donors aged < 40<br> | Other: No intervention, observation study<br>* No intervention, observation study<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Overall survival | The duration from transplant until death resulted from any cause. | From date of transplantuntil the date of death from any cause, assessed up to 60 months. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Relapse-free survival | The time from transplant until death or relapse. | From date of transplant until the date of relapse or death from any cause, assessed up to 60 months. | 
| Cumulative incidence of relapse | The time interval between the transplant and the occurrence of relapse. | From date of transplant until the date of relapse, assessed up to 60 months. |