G-CSF alone vs cyclophosphamide plus G-CSF in PBPC mobilization of patients with lymphoma: results depend on degree of previous pretreatment

We performed a randomized study to compare 'G-CSF alone' (administered at dose of 10mcg/kg/day) and 'cyclophosphamide plus G-CSF' (cyclophosphamide at dose of 4g/m2 and G-CSF at dose of 10 μg/kg/day), as PBPC mobilization schedules in 52 patients with NHL or HD. Randomization was stratified according to the amount of previous chemotherapy (≤2 and >2 lines of previous chemotherapy). Mean CD34+ cell peak in P.B., mean 'Total CD34+ cells' harvested and percentage of patients successfully mobilized, in the group mobilized with 'G-CSF alone' vs the group mobilized with 'cyclophosphamide plus G-CSF', were: 35.3 × 106 vs 45.8 × 106/l (P = 0.3), 5.4 × 106 vs 6.8 × 106/kg (P > 0.9) and 50 vs 61% (P = 0.4). No differences were observed in the stratum of less pretreated patients. However, in the stratum of patients who had previously received more than two lines of chemotherapy, CD34+ cell peak (P = 0.05) and percentage of successful mobilization (P = 0.01) were higher when 'cyclophosphamide plus G-CSF' was used. Using logistic regression, both age and mobilization with 'G-CSF alone' were significantly associated with a low CD34+ cell peak in P.B. However, in the stratum of less pretreated patients, only age was significantly associated with this risk.