To collect information about the patient's leukemia and to seek the optimal treatment for children with ALL based on the individual level of risk of the cancer coming back after treatment. The risk groups are defined as a result of recent research conducted by the Children's Oncology Group (COG). We would like to learn if the use of an experimental intrathecal therapy (ITT), which has been given to many people with ALL and has been well tolerated, would be better at preventing relapse in the central nervous system and improve disease outcomes in children with High Risk ALL.

The Center for International Blood and Marrow Transplant Research (CIBMTR ) keeps a research database. It uses this database to collect and study the medical data for patients that have received Hematopoietic Cell Transplantation, Other Cellular Therapies and Marrow Toxic Injuries. It also collects and studies data from donors who give bone marrow or peripheral blood stem cells (PBSCs). These therapies are used to treat cancer and other diseases. The purpose of this study is to add more data to the database. Participants will have medical data (data about their disease, transplant or cellular therapy) collected before and after transplant cellular therapy, and once a year afterwards for life.

The primary purpose of the Research Sample Repository is to make blood samples available for research studies related to histocompatibility and hematopoietic cell transplantation (HCT) or other cellular therapy.