Successful mobilisation of peripheral blood stem cells in children using plerixafor: a case report and review of the literature.

Abstract

High-dose chemotherapy followed by autologous peripheral blood stem cell (PBSC) support is a salvage therapy for patients with relapsed or refractory malignant disease. Previous chemotherapy treatments, such as alkylating agents, purine analogues and radiotherapy, are known to affect subsequent mobilisation of PBSC1. On the basis of a history of a previously failed mobilisation attempt or the presence of one or more factors predicting an unsuccessful harvest (advanced disease, prior extensive radiotherapy, prolonged treatment with stem cell poisons, advanced age, or extensive bone marrow involvement) these patients have been identified as “predicted poor mobilisers”2. In fact, in about 10 to 30% of patients it is not possible to collect an adequate number of PBSC to support haematopoietic stem-cell transplantation when growth factor alone or in combination with chemotherapy is used for the mobilisation3. Plerixafor is a new agent that inhibits stromal cell-derived factor-1a/CXCR4 binding, resulting in rapid mobilisation of CD34+ cells into peripheral blood and is well recognised as a solution to save adults in whom conventional mobilisation regimens have failed4,5. In this context, in combination with growth factor, plerixafor leads to successful mobilisation in 70% of adult patients with non-Hodgkin’s lymphoma, Hodgkin’s lymphoma and multiple myeloma6. Give the low rate of poor mobilisation in children, few experiences have been reported regarding the use of plerixafor in this context7–11. Since Plerixafor is not yet authorised as a standard mobilising regimen in paediatric patients its administration should be considered as off-label therapy, thus requiring parental informed consent. A European Bone Marrow Transplantation (EBMT) study is currently investigating the off-label use of plerixafor (“Non-interventional study on the off-label transplant use of plerixafor”). Here we describe our experience using plerixafor on demand to mobilise PBSC in a young patient with Hodgkin’s lymphoma.