To examine the outcomes associated with granulocyte colony stimulating factors (G-CSFs) administered as primary versus secondary prophylaxis in setting of bendamustine plus rituximab (BR) regimens.
Eighty-five patients who underwent treatment for non-Hodgkin’s lymphoma (NHL) or chronic lymphocytic leukemia (CLL) with BR at the University of Arizona Cancer Center from November 2013 to June 2019 were evaluated through retrospective chart review. Patients were stratified into two groups: those who were given G-CSF for primary prophylaxis (n = 47) and for secondary prophylaxis (n = 38). G-CSF-included filgrastim or pegfilgrastim. The primary endpoints were incidence of febrile neutropenia and grade 3 or 4 neutropenia.
Same-day G-CSF compared with next-day G-CSF was the most common G-CSF dosing method utilized in primary and secondary prophylaxis (94% and 100%), respectively. Primary and secondary prophylaxis groups were similar on baseline characteristics (p > 0.05); the primary outcome of FN (p > 0.05); all secondary outcomes (p > 0.05) except for a higher frequency of dose delays in secondary (40%) vs primary prophylaxis patients (13%; p = 0.01), and mean absolute neutrophil counts (ANC) in cycles 1 through 5. With higher ANC levels observed during all cycles in the primary prophylaxis group compared with secondary prophylaxis.
In this single-center retrospective study, BR-treated lymphoma and CLL patients receiving primary versus secondary with G-CSF showed similar outcomes except, notably, for chemotherapy dose delays that may put secondary patients at risk for poor treatment outcomes. Further research is needed to evaluate the impact of primary versus secondary prophylaxis on treatment outcomes.