SIRPA and neoplasm: Monocytes readily engulf bloodborne tumor‐derived material such as exosomes and large microparticles, indicating that monocyte‐mediated phagocytosis could be an important part of the antitumoral immune response.3, 64 However, cancerous cells are able to shield themselves from phagocytosis in circulation and within primary tumor sites, for example, through expression of CD47.65, 66 Circulating monocytes express high levels of SIRPα (CD172a), the ligand for CD47, but CD47/SIRPα interactions have not been extensively explored in monocyte‐mediated phagocytosis of tumor cells.