However, NGS in this case revealed the hallmark loss of E-cadherin (CDH1, c.476del) within the lobular breast carcinoma (metastatic to the ovary) which was not identified within the uterine carcinosarcoma which makes it difficult to consider loss of CDH1 as a driver mutation for both tumors. This evidence concerns the gene CDH1 and uterine carcinosarcoma.