Then, we evaluated the association of SOX9 expression with the clinical and pathologic parameters of thymoma cases from TCGA dataset, including age, sex, histological type, history of myasthenia gravis, Masaoka stage, radiation therapy, and new tumor event after initial treatment, and found that SOX9 expression was correlated with the histological type of thymomas (Table 2, P < 0.001). This evidence concerns the gene SOX9 and thymoma.