An adenocarcinoma arising from the uterine body cavity. This is the most frequent malignant tumor affecting the uterine body, and is linked to estrogen therapy. Most patients present with uterine bleeding and are over age 40 at the time of diagnosis. The prognosis depends on the stage of the tumor, the depth of the uterine wall invasion, and the histologic subtype. Endometrioid adenocarcinoma is the most frequently seen morphologic variant of endometrial adenocarcinoma.