Influence of Diabetes On Autologous Hematopoietic Stem Cell Mobilization

Recent experimental data in murine studies suggests that hematopoietic stem cells (HSC) may not mobilize as well in mice with diabetes (DM) compared to non-diabetic mice. We performed a retrospective study of patients with and without DM undergoing first autologous stem cell mobilization from 1/1/2009 to 1/1/2012 to compare efficiency of mobilization and collection of CD34+ cells.  Method of mobilization was decided by the attending physician. Chemotherapy and G-CSF were used if therapy or cytoreduction was necessary and, per institutional guideline, cytokine only mobilization was G-CSF 10 ug/kg daily with apheresis starting on day 5, and plerixafor 0.24 mg/kg was added on day 4 if the peripheral blood CD34+ cells/ul was < 15. A total of 343 pts underwent 362 attempts at collection with 56 (15%) having type II DM. Failure to mobilize CD34 cells was defined as never reaching 10 or greater peripheral blood CD34+ cells/ul, or collecting less than 2 million CD34+ cells/kg. Both DM and non-DM pts required a median of 2 (range 1-4) days of apheresis for successful collection. The mean total CD34+ cells/kg x 10⁶ collected (std dev) was 6.12 (2.66) in DM pts vs 6.8 (3.58) in non-DM pts (p=0.05).  When stratified by method of mobilization, the mean and median total CD34+ cells collected were less, and the mean days of apheresis were more in DM pts, but this did not reach statistical significance.  Overall, 11/343 (3.2%) pts failed to mobilize adequate CD34+cells and did not proceed to autologous HSC transplant, with 4 of the 11 (36%) having DM. Engraftment and day 100 transplant outcomes were not different between pts with and without DM. In conclusion, pts with DM may mobilize less CD34 + cells, but this appears to be a small effect that is primarily overcome by current methods of mobilization, with the majority of patients still able to proceed to autologous HSC transplant. Larger studies may be warranted to discern if DM pts may benefit from different methods of mobilization or if long term transplant outcomes are impacted.