CSF3 and neutropenia: However, primary G-CSF prophylaxis did not have a significant effect on OS (14.7 vs. 8.8 months; HR 1.519; 95% CI 0.878–2.629), while reducing the risk of neutropenia (19.0% vs. 47.6%, p = 0.028) and not significantly reducing the risk of febrile neutropenia (4.8% vs. 21.4%, p = 0.088) with similar cRDI (72.2% vs. 70.1%, p = 0.334) in the older patient group.