Unlike normal tumor-associated macrophages, which exert high pro-tumor activity, activated Sirpα-deficient intratumoral macrophages exhibit a superior antitumor capacity and function as proinflammatory phagocytes and immunogenic APC that transform the TME into a tumoricidal niche highly infiltrated by tumor-killing cytotoxic T cells, NK cells, and inflammatory neutrophils, but with limited immunosuppressive cytokines, Tregs and MDSC. This evidence concerns the gene SIRPA and neoplasm.