Solitary fibrous tumors (SFT) are uncommon fibroblastic neoplasms. Often diagnosed by their histological characteristics and CD34 expression, these tumors present a very broad histological spectrum and occasionally an unexpected immunophenotype. Through molecular analyzes it has been shown that most SFTs express the NAB2-STAT6 fusion protein. Recent studies have suggested that IHC is an effective way to detect this fusion protein, making STAT6 a marker for unconventional SFT cases.