We believe that it is necessary to carry out a further investigation on STAT3 gene, which may improve the precision of clinical diagnosis of thymic epithelial tumor, provide genetic diagnostic proofs, help the physicians make a precise forecast for their patients, provide new targets in genetically targeted therapy for thymic epithelial tumor patients, and have a great importance in genetic therapy for malignant thymic epithelial tumors not responsive to radiotherapy and/or chemotherapy. Here, STAT3 is linked to thymic epithelial neoplasm.