The primary aim of this trial is to ascertain whether or not systematic pelvic and para-aortic lymphadenectomy (LNE) does have a significant impact on overall survival (OS) in patients with endometrial cancer (EC) FIGO Stages I or II and high risk of recurrence. Secondary aims will be to evaluate the effect of LNE on disease free survival (DFS) and quality of life, as well as the complications and side effects of LNE and the number of resected lymphnodes. 640 patients with histologically confirmed EC with high risk of recurrence (stage pT1b - pT2, all histological subtypes; pT1a, G3 endometrioid or serous or clear cell EC or carcinosarcomas) will be randomized. In Arm A, a total hysterectomy and bilateral salpingo-oophorectomy and in case of serous or clear cell EC additionally an omentectomy will be performed. In arm B in addition a systematic pelvic and para-aortic LNE up to the level of the left renal vein will be performed.