STAT6 and cancer: IHC plays a significant role in making a definitive diagnosis.12 IHC findings in intrapulmonary SFT are similar to those in pleural SFT.16,17 The most important positive markers in SFT are CD34, Bcl-2, STAT-6 which usually show diffuse and strong expression.16,18 Expression of CD34 has been observed in 81–95% of SFTs but is lost in malignant tumors.