STAT6 and solitary fibrous tumor: The fusion gene NAB2/STAT6 and its variants confirm a diagnosis of SFT in those cases with unconvincing STAT6 immunoreactivity, and specific gene fusions have been related to prognosis and tumor location [6,7,8,9,10,11,12,13,14,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40].