Lenalidomide is an agent that has shown great activity in patients with multiple myeloma. However, studies have suggested that this drug negatively affects subsequent stem cell collection. To investigate whether lenalidomide impairs stem cell mobilization and collection, we reviewed data for patients with multiple myeloma who underwent mobilization with filgrastim. Predictors of mobilization failure were evaluated using logistic regression analysis. In 26 (9%) of 302 myeloma patients, stem cell mobilization failed. Mobilization failed in 25% of patients who had previously received lenalidomide, compared with 4% of patients who had not received lenalidomide (P < .001). In a multivariate analysis, prior lenalidomide use (odds ratio, 5.9; 95% CI, 2.4 to 14.3) and mobilization more than 1 year after diagnosis (odds ratio, 4.6; 95% CI, 1.9 to 11.1) were significantly associated with failed mobilization. Twenty-one of 26 patients in whom mobilization with filgrastim failed underwent remobilization with chemotherapy and filgrastim; in 18 (86%) of these 21 patients, stem cells were successfully mobilized and collected. In patients with multiple myeloma, prior lenalidomide therapy is associated with failure of stem cell mobilization with filgrastim. Remobilization with chemotherapy and filgrastim is usually successful in these patients.

Background-Iron overload has been associated with increased non-relapse mortality (NRM) in patients with acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) undergoing hematopoietic stem cell transplantation (HSCT). Elevated ferritin level pre-HSCT has been used as a marker for iron overload. It is unclear whether the negative effect of iron overload as measured by elevated ferritin level extends beyond the first three months post HSCT, as this would suggest a potential role for active management of iron overload post HSCT.