Since the work of Bokhman, endometrial cancer has been divided histologically into two types, type I and type II.
Type I: It represents 80% of the total of cases of endometrial cancer and corresponds to endometrioid adenocarcinoma, so named because it histologically mimics the normal endometrium. There are several subtypes such as villoglandular, secretory and ciliated cells.
Type II: Represents 20% of the total of cases of endometrial cancer. There are different histological subtypes, being the papillary serous the most aggressive with invasion both to the myometrium and intra-vascular space with consequent poor prognosis. The remaining histological subtypes such as clear cell, mucinous, among other are less frequent.
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