Breast tumors infiltrated by MMP-11+ mononuclear inflammatory cells are more likely to metastasize, have high levels of interleukin (IL)-1, IL-5, IL-6, IL-17, interferon (IFN), and NFB, and an increased CD68+/(CD3+CD20+) cell ratio at the invasive front. The gene discussed is IL1B; the disease is breast neoplasm.