Effect of thalidomide on stem cell collection and engraftment in patients with multiple myeloma.

The purpose of this study was to determine the effect of thalidomide on stem cell collection and engraftment in patients with multiple myeloma. We performed a retrospective review of 67 patients newly diagnosed with multiple myeloma at Mayo Clinic and treated with a single regimen prior to stem cell transplantation between January of 2000 and September of 2001. Stem cells were collected from 24 patients who received thalidomide, 200 mg/day, with dexamethasone as initial therapy before stem cell collection. These patients were compared with 43 control patients seen during the same period who had received only one previous regimen before stem cell collection and transplantation. The cumulative thalidomide dose before stem cell collection was 17 000 mg over a median of four cycles (range, 2-7 cycles). The thalidomide and control groups were not significantly different in their baseline characteristics, number of stem cells collected, time to collection, or time to engraftment of neutrophils or platelet count of 50 000/microl. Time to platelet count of 20 000/microl was delayed by a median of 4 days (P=0.008), but platelet transfusion requirements did not differ (P=0.95). We concluded that thalidomide does not substantially affect peripheral cell mobilization or engraftment.