Both randomised groups are treated with surgery for complete resection following guideline recommendations and including median laparotomy, complete adhesiolysis, hysterectomy, bilateral salpingo-oophorectomy, omentectomy and (partial) resection of all affected organs (e.g. small or large bowel, peritoneum, spleen, pancreas, peritoneum, urinary tract etc.) as well as pelvic and paraaortic lymphadenectomy if indicated. Patients with significant pleural effusion (>500 mL in the right chest or any pleural effusion in the left chest, assessed either through ultrasound or CT scan) need to undergo video assisted thoracoscopy or open assessment of the pleura prior or during debulking surgery to detect and if possible remove intrathoracic disease.