This book overviews cancer immunity from broad scientific fields, based on the concept that cancer is a sort of by-product of infection, inflammation, and host immune response. The innate and acquired arms of the immune system mainly participate in tumor immune surveillance, and their activation is critically modulated by the situation of the tumor microenvironment. Many types of immune cells join the formation of the microenvironment. In particular, macrophages and dendritic cells enter the tumor mass to be main players in the inflammatory milieu of tumors. After introducing these topics,...