CSF1 and neoplasm: As tumour cells release the diffusible chemoattractant colony stimulating factor-1 (CSF-1), M1-like macrophages with phenotype \documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$p_i = 0$$\end{document} extravasate from blood vessels and move towards tumour cells to kill them.