Treatment of relapse after allogeneic stem cell transplantation in children and adolescents with ALL: the Frankfurt experience
Relapse after allogeneic stem cell transplantation in ALL patients is very challenging to treat and there is no standardized treatment approach. In this study, the latest experience from the Frankfurt group is presented, describing a curative second transplant and an experimental non-transplant approach for treatment of post transplant relapse.
In this single center retrospective study, outcomes of all relapsed pediatric ALL patients treated in Frankfurt between 2005 and 2014 were analysed. The treatment strategy was to treat all patients who were in good clinical condition with high dose chemotherapy or specific immune-therapy to induce remission followed by a second transplant from a haploidentical donor conditioned with clofarabine, cyclophosphamide, etoposide, alemtuzumab and fludarabine. If a second transplant was not clinically feasible, a combination of low dose chemotherapy and donor lymphocyte infusions was offered.
A total of 23 out of 101 pediatric ALL patients relapsed after their first SCT during the study period. Seven patients were treated with a second transplant after responding to salvage chemo/immune therapy, out of which five remained in CR. Ten patients who where not clinically feasible for a second transplant were treated with low dose chemotherapy and DLI out of which four remained in CR. Four-year overall survival for the transplant approach was 56% and for the experimental non-transplant approach 40%.
This is a retrospective single center study with a very limited number of patients and no control group. Treatment group was directed largely by physician decision thereby introducing bias.