In breast cancer, tumor necrosis has been shown to correlate with increased tumor size, high-grade disease, high microvessel density, and infiltrates of macrophages that express vascular endothelial growth factor, suggesting that hypoxic environment causing tumor necrosis stimulates angiogenesis owing to angiogenic growth factors released by infiltrating macrophages in rapidly growing tumors [23, 29, 30]. The gene discussed is VEGFA; the disease is breast cancer.