An investigation of Chen et al. on global methylation levels and the promoter methylation status of tumor suppressor genes (TSG) hMLH1, MGMT, p-16INK4a, RASSF1A, FHIT, APC1A, RARB, DAPK, and E-cadherin in 65 TET samples indicated hypermethylation and reduced TSG expression in types B1 or higher thymomas [45]. This evidence concerns the gene CDH1 and thymoma.