The feasibility and efficacy of subcutaneous plerixafor for mobilization of peripheral blood stem cells in allogeneic HLA–identical sibling donors: results of the HOVON-107 study

Background: Plerixafor (PFX) mobilizes CD34+ cells into circulation by disrupting the CXCR4 binding of the hematopoietic stem cell in its bone marr

Immunophenotypic measurable residual disease (MRD) in acute myeloid leukemia: Is multicentric MRD assessment feasible?

Flow-cytometric detection of now termed measurable residual disease (MRD) in acute myeloid leukemia (AML) has proven to have an independent prognostic impact. In a previous multicenter study we developed protocols to accurately define leukemia-associated immunophenotypes (LAIPs) at diagnosis. It has, however, not been demonstrated whether the use of the defined LAIPs in the same multicenter setting results in a high concordance between centers in MRD assessment. In the present paper we evaluated whether interpretation of list-mode data (LMD) files, obtained from MRD assessment of previously determined LAIPs during and after treatment, could reliably be performed in a multicenter setting. The percentage of MRD positive cells was simultaneously determined in totally 173 LMD files from 77 AML patients by six participating centers. The quantitative concordance between the six participating centers was meanly 84%, with slight variation of 75%–89%. In addition our data showed that the type and number of LAIPs were of influence on the performance outcome. The highest concordance was observed for LAIPs with cross-lineage expression, followed by LAIPs with an asynchronous antigen expression. Our results imply that immunophenotypic MRD assessment in AML will only be feasible when fully standardized methods are used for reliable multicenter assessment

Plerixafor for stem cell mobilization: the current status

Purpose of review Nowadays, plerixafor is approved for patients who fail to mobilize sufficient CD34(+) cells for an autologous stem cell transplantation. Plerixafor is effective in the majority of these patients, who otherwise could not be treated adequately. We discussed in this review the current status of the optimal use of plerixafor in different clinical diagnoses and settings. Recent findings Plerixafor seems to be more effective in patients with multiple myeloma than in lymphoma. Even patients who had very low circulating CD34(+) cells before administration of plerixafor have an important benefit. Several strategies in different clinical settings showed an effective response after administration of plerixafor, without the superiority of one strategy. Plerixafor is well tolerated with acceptable toxicity; however, it is an expensive drug. Summary Plerixafor is an effective drug in patients who fail to mobilize with conventional strategy. No strategy seems superior for the optimal use of plerixafor. More studies focusing on the kinetics and cost-effectiveness are needed