Conditioning regimens for allogeneic stem cell transplantation in children and adolescents with acute lymphocytic leukemia
Overall survival and event-free survival were higher in the group with total body irradiation and treatment-related mortality was higher in the group with chemotherapy
At the plenary session of the Presidential Symposium, during the 25th edition of the EHA Annual Congress, Dr. Christina Peters presented a study on conditioning regimes for allogeneic stem cell transplantation in children and adolescents with acute lymphocytic leukemia (ALL).
The ALL SCTped FORUM study (For Omitting Radiation Under Majority age) aimed to evaluate the possibility of not using TBI (total body irradiation) in the conditioning regimes of children and adolescents, due to the known long-term adverse events caused by irradiation.
In total, 413 patients were enrolled, involving 17 countries. Most of the children were over 10 years old and were transplanted in first remission. Patients were randomized into one arm using TBI and VP16 (etoposide) and the other arm using fludarabine, thiotepa and IV busulfan or thosulfan.
Overall survival and event-free survival were higher in the TBI group and treatment-related mortality was higher in the chemotherapy group. There was no difference in response regarding age. BCR-ABL and hypodiploidy were characteristics of a good prognosis. Surprisingly, minimal residual disease before transplantation was not a criterion for better event-free survival. GvHD (graft versus host disease) was similar in both groups.
In the multivariate analysis, there was no difference between the type of donor, whether or not he had minimal residual disease before BMT (bone marrow transplantation), type of material for BMT (peripheral blood or bone marrow).
There are still many questions to be answered, especially regarding the assessment of late complications and the appearance of a higher incidence of second neoplasms.
