The group of cancers derived from E-cadherin positive normal cells and showing a particularly frequent loss of E-Cadherin expression included highly dedifferentiated cancers such as Merkel cell carcinoma, anaplastic thyroid cancer, dedifferentiated endometrium carcinoma, and sarcomatoid and small cell carcinomas of the urinary bladder. This evidence concerns the gene CDH1 and urinary bladder small cell neuroendocrine carcinoma.