Stem cell mobilization in patients with newly diagnosed multiple myeloma after lenalidomide induction therapy

Lenalidomide has raised concerns regarding its potential impact on the ability to collect stem cells for autologous stem cell transplantation, especially after prolonged exposure. The use of cyclophosphamide plus granulocyte colony-stimulating factor (G-CSF) to mobilize peripheral blood stem cells may overcome this concern. In newly diagnosed multiple myeloma (MM) patients, we investigated the influence of lenalidomide on stem cell collection. In a prospective study, 346 patients received four cycles of lenalidomide-dexamethasone (Rd). Stem cells were mobilized with cyclophosphamide and G-CSF. Patients failing to collect a minimum of 4 × 10(6) CD34(+)/kg cells received a second mobilization course. After mobilization, a median yield of 8.7 × 10(6) CD34(+)/kg was obtained from patients receiving Rd induction. After first mobilization, inadequate yield was observed in 21% of patients, whereas only 9% of patients failed to collect the target yield after the second mobilization attempt. In conclusion, we confirm that a short induction with lenalidomide allowed sufficient stem cells collection to perform autologous transplantation in 91% of newly diagnosed patients.

Mobilization in myeloma revisited: IMWG consensus perspectives on stem cell collection following initial therapy with thalidomide-, lenalidomide-, or bortezomib-containing regimens

The past decade has witnessed a paradigm shift in the initial treatment of multiple myeloma with the introduction of novel agents such as thalidomide, lenalidomide, and bortezomib, leading to improved outcomes. High-dose therapy and autologous stem cell transplantation remains an important therapeutic option for patients with multiple myeloma eligible for the procedure. Before the advent of the novel agents, patients underwent stem cell collection prior to significant alkylating agent exposure, given its potential deleterious effect on stem cell collection. With increasing use of the novel agents in the upfront setting, several reports have emerged raising concerns about their impact on the ability to collect stem cells. An expert panel of the International Myeloma Working Group (IMWG) was convened to examine the implications of these therapies on stem collection in patients with myeloma and to develop recommendations for addressing these issues. Here we summarize the currently available data and present our perspective on the problem and potential options to overcome this problem. Specifically, we recommend early mobilization of stem cells, preferably within the first 4 cycles of initial therapy, in patients treated with novel agents and encourage participation in clinical trials evaluating novel approaches to stem cell mobilization.