STAT6 and neoplasm: Strong and diffuse nuclear immunoreactivity for STAT6 is a very useful tool for the diagnosis of SFTs, although unexpected epithelial, muscular or neuroendocrine marker expression has also been described in these tumors and may lead to confusion with other neoplasms with hemangiopericytic growth patterns [2,15,16,17,18,19,20,21,22,23,24,25,33,42].