A comparison of mobilization regimens used in Hodgkin lymphoma and factors that influence peripheral blood stem cell mobilization.

BACKGROUND: Various chemotherapy regimens have been used for chemo-mobilization of stem cells prior to autologous stem cell transplant in patients with Hodgkin lymphoma, and there is no clear standard of care. In this retrospective study, we analyzed mobilization outcomes and the factors affecting successful mobilization following different salvage chemotherapy regimens used in Hodgkin lymphoma.

OBJECTIVES: The primary objective was to compare success rates of different chemotherapy regimens. Successful mobilization was defined as the ability to harvest at least 2 × 106/kg of stem cells during one mobilization attempt. Secondary objectives were to find factors that influenced mobilization failures.

STUDY DESIGN AND METHODS: This is a single-center, retrospective analysis of all Hodgkin lymphoma patients for whom peripheral blood stem cell (PBSC) mobilization was attempted at Tata Memorial Centre, Mumbai, India between December 1, 2007, and June 30, 2022. Salvage chemotherapy that was being used to treat relapsed/refractory lymphoma was generally preferred as a chemo-mobilization regimen. For patients who had already completed all salvage-chemotherapy cycles, GCSF ± plerixafor was used. Clinical parameters (age, sex, stage, lines of treatment, use of radiation therapy, disease status at time of harvest, platelet count at relapse) and stem cell collection parameters (day of chemotherapy, peripheral blood CD34 cell count on D1 of harvest, number of days of harvest, CD34 cells collected on D1 and total CD34 cells collected) were extracted from medical records and analyzed.

RESULTS: A total of 174 PBSC mobilization attempts were made in 169 Hodgkin lymphoma patients during the study period. Chemo-mobilization with gemcitabine-dexamethasone-platinum (GDP)- and cytarabine-based regimens led to successful harvests in 95% and 100% patients, respectively. GDP-based mobilization was significantly better than other regimens and granulocyte colony-stimulating factor (G-CSF) (±plerixafor) mobilization (82%) (P = 0.000082). Patients who had previous radiation exposure to mediastinum, spine or pelvis and underwent mobilization following ifosfamide-based mobilization had a mobilization failure rate of 37%.

CONCLUSIONS: GDP and cytarabine-based regimen have better mobilization success compared to ifosfamide-based regimen or G-CSF (±plerixafor) in lymphoma patients. It may be best to avoid ifosfamide-based regimens in patients who have received radiation to mediastinum, spine or pelvis due to high rates of mobilization failure.