WFDC2 and atypical endometrial hyperplasia: Therefore, based on the above-mentioned theory, this study detected the expression of HE4 in endometrial cancer, endometrial atypical hyperplasia, and normal endometrium tissue samples with an adequate sample size and explored the relationship between HE4 expression and histological type, stage, differentiation, and prognosis of endometrial cancer, in order to provide a theoretical basis for an in-depth mechanism study of endometrial cancer development.