Chemotherapy Combined with Granulocyte Colony Stimulating Factor (G-CSF) for Mobilization of CD34⁺ Cells in Lymphoma and Multiple Myeloma Patients

Objective: To investigate and analyze factors which effect autologous stem cell collection in patients with lymphoma and multiple myeloma (MM) during chemotherapy combined with G-CSF mobilization, for improving quality and effectiveness of autologous stem cell transplantation.

Methods: A retrospective analysis was performed from April 1, 2006 to October 31, 2013 in our hospital and 128 lymphoma and MM patients whose autologous peripheral blood stem cells (PBSCs) were collected including 75 patients with malignant lymphoma,7 cases of Hodgkin's lymphoma and 68 non-Hodgkin's lymphoma (NHL) cases as well as 53 MM patients were enrolled. The stem cells of all patients were mobilized by chemotherapy combined with G-CSF and collected via a continuous flow cell separation instrument (COBE Spectra, Lakewood, CO). Mobilize failure was defined when the amount of CD34 + cells was less than 2.0 x 106 / kg, whereas ≥2.0 * 106 / kg was defined as successful mobilization. More than 5.0x 106 cells / kg or more was considrered as ideal mobilization. Univariate and multivariate regression analyses of factors for mobilization failure, successful mobilization and ideal mobilization acquisition were performed.

Results: There were more CD34+ cells in MM patients than in lymphoma patients (P = 0.064). The collection rates of CD34 + cells in MM patients were ≥ 2.0 x106 / kg in 64.8% (83 cases) and ≥ 5.0 x 106 / kg in 35.2% (45 cases). MM patients with a success collection ratio was 73.6 % (39/53) and the ideal collection rate was 43.4% (23/53), which was higher than in the NHL group with a success rate and ideal rate of 58.7% (44/75) and 30.7% (23/75). A total of 35.2 % (45 cases, including 31MM cases and 14 lymphoma cases) a mobilization was not successful.

Conclusion: In different chemotherapy regimens in patients with lymphoma, remission, ever use MTX and/or Ara-c treatment and collecting the outer peripheral hematocrit could significantly affect the success rate of stem cell collection; In MM patients, who received lenalidomide treatment and multiple courses of treatment, still not got CR, which these reasons were the factors of non- successful mobilization.Although Plerixafor and peripheral blood CD34-positive cell counts could help to improve the success collection rate and predict collection rate, but there is still a need for further improvement of the current mobilization protocols, recognizing the ideal stem cell collection dynamics, efficiency and cost in order to select the appropriate mobilization protocols.