Stem Cell Mobilization Chemotherapy with Gemcitabine Is Effective and Safe in Myeloma Patients with Bortezomib Induced Neurotoxicity

Background: Vinorelbine chemotherapy with G-CSF stimulation is a widely applied non-myelosuppressive mobilization regimen in Switzerland for myeloma patients, but its neurotoxic potential limits its use in patients with bortezomib induced polyneuropathy. Methods: In this single-center study, we alternatively evaluated safety and effectiveness of gemcitabine chemotherapy with G-CSF for mobilization of autologous stem cells. Results: Between 03/2012 and 02/2013, all bortezomib pretreated myeloma patients planned to undergo first-line high-dose melphalan chemotherapy received a single dose of 1250mg/m2 gemcitabine, with G-CSF started on day four. The 24 patients in this study have received a median of four cycles of bortezomib-dexamethason based induction. Bortezomib-caused polyneuropathy was identified in 21 patients (88%) by clinical evaluation and a standardized questionnaire. Administration of gemcitabine mobilization did not induce novel or aggravate preexisting neuropathy. Stem cell mobilization was successful in all 24 patients, with a single day of apheresis being sufficient in 19 patients (78%). The median yield was 9.51 x 10⁶ CD34+ cells/kg. Stem collection could be accomplished at day 8 in 67%. Conclusion: Our data suggest that single-dose gemcitabine together with G-CSF is an effective mobilization regimen in myeloma patients and a safe alternative non-myelosuppressive mobilization chemotherapy for myeloma patients with bortezomib induced polyneuropathy.