Again, the use of prophylactic G-CSF therapy in this setting is experimental, as the main chemotherapy regimens administered (oxaliplatin, fluorouracil, and leucovorin [FOLFOX4] or irinotecan, fluorouracil [infusion], and leucovorin [FOLFIRI]) have been reported to have a 6 and 9% incidence of FN, respectively, in patients with advanced colorectal cancer (Smith et al. 2006). Here, CSF3 is linked to colorectal cancer.