Date Published: November 29, 2011
Publisher: Hindawi Publishing Corporation
Author(s): Jan S. Moreb, Donya Salmasinia, Jack Hsu, Wei Hou, Christina Cline, Emma Rosenau.
Poor peripheral blood stem cell (PBSC) mobilization predicts worse outcome for myeloma and lymphoma patients post autologous stem cell transplant (ASCT). We hypothesize that PBSC harvest using plerixafor and G-CSF in poor mobilizers may improve long-term outcome. We retrospectively analyzed the data on patients who had second PBSC mobilization using plerixafor and G-CSF as a rescue. Nine lymphoma and 8 multiple myeloma (MM) patients received the drug. A control group of 25 MM and lymphoma patients who were good mobilizers with G-CSF only was used for comparison. Sixteen of the 17 poor mobilizers proceeded to ASCT, and one MM patient had tandem transplants. Length of hospital stay, infection incidence, granulocyte engraftment, and long-term hematopoietic recovery were not significantly different between the two groups. In conclusion, all poor mobilizers were able to obtain adequate stem cells transplant dose and had similar transplant course and long-term outcome to that of the control good mobilizers group.
The use of peripheral blood stem cells (PBSCs) for autologous and allogeneic transplantation has increased significantly in recent years. According to the Center for International Blood and Marrow Transplant Research (CIBMTR) , more than 95% of autologous stem cell transplants (ASCTs) and more than 70% of allogeneic stem cell transplants are carried out with mobilized PBSC. The advantages of using PBSC over bone marrow include shorter engraftment time, less transfusions, shorter hospital stay, convenience of stem collection, and rapid restoration of the immune system [2–5].
The addition of plerixafor to G-CSF as first line regimen for peripheral blood stem cell (PBSC) mobilization has been shown to be safe and effective in two phase III placebo-controlled randomized studies in MM and NHL patients undergoing ASCT [15, 16] as well as in multiple phase II and retrospective studies in hard-to-mobilize patients [7, 14, 17, 19–21]. Plerixafor has been offered to patients who failed prior mobilization attempts on a compassionate use protocol (CUP) by Genzyme. The European compassionate use data has been recently published . Total of 56 patients from 15 centers in Spain and the UK were analyzed. The results showed that 75% of patients collected ≥2 × 106 CD34+/kg and that 63% underwent transplant. All patients engrafted neutrophils and PLTs. Followup was up to 6 months during which 3 patients died from disease progression (2) or viral pneumonitis (1). Five patients failed to mobilize adequately with plerixafor and G-CSF and were not able to proceed to ASCT. Two other publications from the CUP study showed success rates for plerixafor plus G-CSF of 66–85% [17, 20, 21].
Our results confirm the effectiveness of plerixafor in mobilizing and harvesting PBSC from lymphoma and myeloma patients who failed G-CSF mobilization and therefore allowing more patients to undergo ASCT. In addition, our study also show comparable long-term engraftment and hospital course for these poor mobilized patients in comparison to control good mobilized group.