02.The large fronds of endometrium seen in this uterus opened to reveal the endometrial cavity are a result of hyperplasia. This resulted from increased estrogen. With hyperplasia, there is an increase in cell numbers to produce an increase in tissue size.However, the cells are normal in appearance. Sometimes hyperplasias can be "atypical" and the cells not completely normal. Such conditions can be premalignant.

02.图示暴露的宫腔内显著折叠的宫内膜，为宫腔内膜增生之例，来源于雌激素过多所致细胞数目增加,体积增加。但细胞形态正常。有时增生呈不典型，细胞不完全正常，可为恶变前改变。