Efficacy and Safty of Stem Cell Mobilization with Etoposide +Cytarabine Plus G-CSF in Patients with Lymphoma at High-Risk of Mobilizing Failure

Objective：Sufficient peripheral blood stem cell (PBSC) mobilization is important for performing successful autologous stem cell transplantation (ASCT) in patients with lymphoma. However, the optimal mobilization strategy remains a matter of debate in lymphoma.The aim of the study was to explore efficacy and safety of PBSC mobilization using etoposide combined with Cytarabine (EA) plus G-CSF in patients with lymphoma at high-risk of mobilizing failure.

Methods：This retrospective study explored efficacy and safety of PBSC mobilization using EA (etoposide 50~100 mg/m2 , qd d1~3; AraC 0.5 g/m2 , q12h d1~3) plus G-CSF (5 µg/kg/day, from d5 until the day of apheresis) in 81 patients with lymphoma at high-risk of mobilizing failure. As previously reported, patients were defined at high-risk of mobilizing failure if (i) previous collection attempts failed (no special instructions); (ii) previous extensive radiotherapy or a complete course of treatment had affected stem cell activity; or (iii) any of these conditions: advanced disease (2 lines of chemotherapy), refractory disease, extensive bone marrow involvement or cellularity <30% at the time of mobilization or age 65 years.

Results：The mean total and first apheresis trial CD34+ cells collection was 20.37(range 1.08~138.96) and 18.56(range 0.1~138.96)×10^6 CD34+ cells/kg, respectively. Overall, 79(97.5%) patents harvested adequate mobilization (≥2×10^6 CD34+ cells/kg), while 65(80.2%) patients achieved optimal mobilization(≥5×10^6 CD34+ cells/kg). A single apheresis was sufficient to reached the target yield of adequate apheresis in 67(82.7%) patients on median 15th day (range 11~19). We observed acceptable hematological toxicity and exposure of antibiotic usage in 57 patients with a median of 4 days. No severe infections or mobilization-related mortality were observed.

Conclusion：Our resluts suggest that EA plus G-CSF is an effective and safe PBSC mobilization strategy for patients with lymphoma, including those predicted as poor mobilizers. The outcome should be evaluated in a randomized study.