Several randomized controlled trials demonstrated a significant reduction in FN after systemic chemotherapy with the use of prophylactic G-CSF compared with untreated controls, and a recent meta-analysis on the proactive use of G-CSF as primary prophylaxis revealed a significant reduction in the risk of FN (RR = 0.54) and infection-related mortality (RR = 0.55) with this strategy, together with a significant increase in the relative dose intensity of the chemotherapy administered (+8.4% on average) [8]. Here, CSF3 is linked to infection.