All articles citing the expression of HE4 in the tissue of pathologically diagnosed endometrial cancer or atypical endometrial hyperplasia were independently identified by three authors (V.M., M.L.F., and M.P.)who conducted a search limited to text words on the following three English databases: PubMed, Web of Science, and Scopus. This evidence concerns the gene WFDC2 and atypical endometrial hyperplasia.