A bone marrow transplant (BMT), also known as a stem cell transplant, is a procedure that places (transplants) healthy blood stem cells into a body where the stem cells have been destroyed by chemotherapy or radiation. It may be seen as a method to ‘rescue’ your child from the severe side effects of high dose chemotherapy and radiation. When the stem cells come from another person, the procedure is called an allogeneic BMT.
Your child may be recommended to have a BMT, depending on whether they have high-risk or low-risk AML. The risk category of your child’s AML depends on the type of chromosome changes that occur inside leukemic cells.
Low-risk AML
Unless your child has a poor response to induction therapy or relapses, BMT is not recommended for low-risk groups of AML.
High-risk AML
AML is categorized as high-risk based on genetic changes in the leukemia cells or poor response to induction therapy (as indicated by a positive minimal residue disease test of greater than 0.1%). In healthy cells, chromosomes exist in pairs. Each pair is numbered from 1 to 23. Some children with AML have leukemic cells that are missing one chromosome from a pair. These children are considered to have high-risk AML, and are recommended for a BMT. The high-risk groups of AML include:
- Monosomy 5/del (5q). This happens when one copy of chromosome 5 is missing.
- Monosomy 7. This happens when one copy of chromosome 7 is missing.
- Presence of FLT3/ITD mutations of greater than 0.4.
For more information, please see the Blood and Marrow Transplant Learning Hub.