Radicality in primary surgical management in gynaecological cancers, especially in ovarian cancer, is the most important factor influencing patient survival. Postoperative residual tumour is one of the most important prognostic factors in ovarian cancer. Radical pelvic and paraaortic lymphadenectomy is recommended in cases of complete resection because of the high incidence of lymph node metastases, especially in the high paraaortic region. A multicenter, prospective randomised study of advanced ovarian cancer by the AGO Ovarian Cancer Study Group is planned to analyse the therapeutic impact of systematic lymphadenectomy in ovarian cancer.