MKI67 and neoplasm: Necroses develop in hyperproliferating areas, with a high Ki-67/MIB.1 LI and a high Nestin expression in comparison with GFAP, due to the focal insufficiency of neoangiogenesis to feed a very large number of tumor cells, because of the imbalance between the high tumor cell proliferation capacity and the low one of endothelial cells [32, 38, 39].