Based on the expressions of the four antibodies and their ROC curve, the combination of IFITM1, CD10, SMA, and h-caldesmon four antibodies showed the highest predictive value of AUC, and the ROC values of other combinations are lower than this type of combination (Table 3, Fig. 2), we speculate that their combinations could be helpful in the differential diagnosis of EST and CL. The gene discussed is IFITM1; the disease is mediastinal yolk sac tumor.