Flow cytometry experiments revealed that during the early stages of tumor development, the macrophage compartment in Brca1co/coMMTV-Cre lesions was dominated by CD11b+Gr‐1−F4/80Low blood‐derived macrophages, accounting for nearly 90% of CD11b+Gr‐1− cells (Fig. 1C). This evidence concerns the gene ITGAM and neoplasm.