on behalf of the European Organisation for Research and Treatment of Cancer-Gynaecological Cancer Group (EORTC-GCG), Groupe d’Investigateurs Nationaux pour les Etudes des Cancers de l’Ovaire (GINECO), Austrian Arbeitsgemeinschaft für Gynäkologische Onkologie (A-AGO), National Cancer Research Institute (NCRI), Australia New Zealand Gynaecological Oncology Group (ANZGOG), and the Mario Negri Gynecologic Oncology group (MaNGO)