The childhood cancer experience necessarily impacts the entire family. In this context, particular attention should be paid to the donor siblings of hematopoietic stem cells in the context of treatment of leukemia by grafting.

The results of the little existing work on the long-term fate of stem cell donor siblings of cancer survivors report psychosocial consequences, particularly for real post-traumatic stress in distant siblings.

Few studies have explored the medium and long-term impact of the disease, as well as donation, on a broader set of domains structuring the quality of life, through validated quantitative tools.

In France, since 2004, the LEA program (Leukemia of the Child and Adolescent) aims to assess the determinants of the state of health and quality of life in the medium and long term, patients treated for acute childhood leukemia after 1980.

The main objective of this study is to evaluate, at a distance from the transplant, the quality of life of donors from the siblings of survivors of acute childhood leukemia who received a hematopoietic stem cell transplant compared with non-donor siblings.

The SIDONY ancillary study will be proposed to families of LEA patients who have received a geno-identical sibling haematopoietic stem cell transplant (population of interest) and to families whose LEA patient has not been treated by sibling transplantation. geno-identical but still declaring to have siblings (main comparator group). Each family will be contacted by mail and the management of inclusions will be managed by the Epidemiology and Health Economics Department of AP-HM (Marseille).

Information not routinely available in the LEA database will be collected from the siblings (self-questionnaire, in addition, for each surviving child included in the cohort, data are available: sociodemographic; characteristics of the initial disease and therapeutic received; physical sequelae; quality of life.

The population meeting the inclusion criteria represents 2639 subjects: 337 donors and 2302 non-donors, making it possible to obtain high powers for analyzes (linear regression, multilevel analyzes, etc.). This study could identify profiles of siblings for whom the quality of life seems particularly impaired, potential object of individual interventions (remediation ...).

The childhood cancer experience necessarily impacts the entire family. In this context, particular attention should be paid to the donor siblings of hematopoietic stem cells in the context of treatment of leukemia by grafting.

The results of the little existing work on the long-term fate of stem cell donor siblings of cancer survivors report psychosocial consequences, particularly for real post-traumatic stress in distant siblings. disease. Few studies have explored the medium and long-term impact of the disease, as well as donation, on a broader set of domains structuring the quality of life, through validated quantitative tools.

In France, since 2004, the LEA program (Leukemia of the Child and Adolescent) aims to assess the determinants (medical, socio-economic, behavioral and environmental) of the state of health and quality of life in the medium and long term, patients treated for acute childhood leukemia after 1980. To document the quality of life of their self-reported hematopoietic stem cell donor siblings and their perception of the impact that experience of cancer in the family has had on their medium and long-term future, the organization of the LEA program can easily be extended to the establishment of an ancillary study.

objectives The main objective of this study is to evaluate, at a distance from the transplant, the quality of life of donors from the siblings of survivors of acute childhood leukemia who received a hematopoietic stem cell transplant compared with non-donor siblings.

The secondary objectives are: (a) to compare the quality of life of siblings with that of the general population; (b) to compare the quality of life of the siblings with that of the surviving patients; (c) to identify the determinants (demographic, socioeconomic, family and history of cancer) of the medium-long-term quality of life of this family; (d) remotely evaluate the donation's use of the donor sire care system as a tracer of the impact of the donation; (e) remotely evaluate the gift of the social integration of the donor sibship, particularly in terms of schooling.

The SIDONY ancillary study will be proposed to families of LEA patients who have received a geno-identical sibling haematopoietic stem cell transplant (population of interest) and to families whose LEA patient has not been treated by sibling transplantation. geno-identical but still declaring to have siblings (main comparator group). Each family will be contacted by mail and the management of inclusions will be managed by the Epidemiology and Health Economics Department of AP-HM (Marseille).

Information not routinely available in the LEA database will be collected from the siblings (self-questionnaire, to be returned by post): sociodemographic and socio-economic data relating to the siblings and the family; data concerning the quality of life of the siblings; psycho-behavioral and cognitive data; data on the state of health of the siblings; social inclusion data; recourse to the health care system. In addition, for each surviving child included in the cohort, data are available: sociodemographic; characteristics of the initial disease and therapeutic received; physical sequelae; quality of life.

Feasibility and practical impact The population meeting the inclusion criteria represents 2639 subjects: 337 donors and 2302 non-donors, making it possible to obtain high powers for analyzes (linear regression, multilevel analyzes, etc.). This study could identify profiles of siblings for whom the quality of life seems particularly impaired, potential object of individual interventions (remediation ...).

Inclusion Criteria:

1. experimental group familly:

   • child included in the LEA cohort
   • having received allogeneic treatment of geno-identical sibling haematopoietic stem cells

2. Criteria for the inclusion of siblings (experimental group)

   • be the brother (or sister) donor of hematopoietic stem cells
   • currently at least 8 years old
   • give consent to participate in the study
   • be allowed to participate in the study by his parents or legal representatives

3. Control group familly

   • child included in the LEA cohort
   • who did not benefit from allogeneic hematopoietic stem cell transplantation of geno-identical siblings
   • and declaring having a sibling

4. Criteria for the inclusion of siblings (control group)

   • currently at least 8 years old
   • to be the closest brother (or sister) in the LEA patient's age (in the case of multiple siblings)
   • give consent to participate in the study
   • be allowed to participate in the study by his parents or legal representatives In order to respect the balance within the family, a questionnaire may be distributed to other brothers and sisters who claim it.

Exclusion Criteria:

not to be allowed to participate in the study by his parents or legal representatives