CSF1 and neoplasm: Macrophage colony-stimulating factor (M-CSF or CSF-1), produced by various cells including tumor cells, macrophages and fibroblasts, is a potent chemotactic factor of mononuclear macrophages and drives the differentiation of macrophages into immunosuppressive M2 phenotype within the TME (67), associated with unfavorable clinical prognostic indicators (28).