Röpke et al. [37] investigated the DNA methylation status of 8 tumor suppressor genes in a dedifferentiated CS case and found p16INK4A and E-cadherin promoter hypermethylation in both dedifferentiated CS sites, whereas methylation of the FHIT promoter was found only in the highly malignant dedifferentiated tumor component. The gene discussed is CDH1; the disease is Cowden syndrome 1.