Remobilization of patients who fail to achieve minimal progenitor thresholds at the first attempt is clinically worthwhile

A significant proportion of previously treated patients fail to mobilize su fficient stem/progenitor cells to enable high-dose therapy and peripheral b rood stem cell transplantation to be performed, In this study, the value of remobilizing such patients has been evaluated in 20 patients who all faile d to achieve progenitor yields of 1 x 10(6)/kg CD34(+) cells and 1 x 10(5)/ kg granulocyte-monocyte colony-forming units (GM-CFCs) at the first attempt , Most patients remained relatively poor mobilizers at the second mobilizat ion, but the yield of CD34(+) cells and GM-CFCs on the first apheresis was significantly greater with the second mobilization than the first. A total yield (all aphereses from both mobilizations) of >1 x 10(6)/kg CD34(+) cell s and >1 x 10(5)/kg GM-CFCs was achieved in 14 out of 20 patients. Seven pa tients have received high-dose therapy with stem cell infusion; neutrophil recovery was rapid in all patients and platelet independence occurred in < 21 d in five out of sewn patients. We conclude that remobilization is worth considering in those patients in whom a chemotherapy-free interval of seve ral months is possible.