CSF2 and neoplasm: Together with MDSCs123 and macrophages,124,125 neutrophil granulocytes, which are especially enriched in CRC, form a complex network of phagocytosing and immunomodulatory immune cells.126,127 Similar to macrophages, difficulties in the classification and functional characterisation of these cells make directed interventions difficult; however, it is clear that multiple interventions (including GM-CSF, VEGF and chemokine inhibition) can modulate these cells and therefore alter the immunological microenvironment of the tumour.