Hyperthermic intraperitoneal chemotherapy for recurrent ovarian cancer (CHIPOR): a randomised, open-label, phase 3 trial.

BACKGROUND

Hyperthermic intraperitoneal chemotherapy (HIPEC) at interval cytoreductive surgery for ovarian cancer improves overall survival but its role in recurrent disease is uncertain. We aimed to compare outcomes in patients treated with or without HIPEC during surgery for recurrent ovarian cancer.

METHODS

The multicentre, open-label, randomised, phase 3 CHIPOR trial was conducted at 31 sites in France, Belgium, Spain, and Canada, and enrolled patients with first relapse of epithelial ovarian cancer at least 6 months after completing platinum-based chemotherapy. Eligible patients were aged 18 years or older with WHO performance status of less than 2. After six cycles of platinum-based chemotherapy (and optional bevacizumab), patients amenable to complete cytoreductive surgery were randomly assigned centrally in a 1:1 ratio, using a web-based system and a minimisation procedure, during surgery to receive HIPEC (cisplatin 75 mg/m2 in 2 L/m2 of serum at 41±1°C for 60 min) or not, stratified by centre, completeness of cytoreduction score, platinum-free interval, and latterly, planned poly(ADP-ribose) polymerase inhibitor use. The primary endpoint was overall survival, analysed on an intention-to-treat basis in all randomly assigned patients. This ongoing trial is registered with ClinicalTrials.gov, NCT01376752.

FINDINGS: Between May 11, 2011, and May 14, 2021, 415 female patients were randomly assigned (207 HIPEC, 208 no HIPEC). At the primary analysis (median follow-up 6·2 years, IQR 4·1-8·1), 268 (65%) patients had died (126 [61%] of 207 in the HIPEC group; 142 [68%] of 208 in the no-HIPEC group). Overall survival was significantly improved with HIPEC (stratified hazard ratio 0·73, 95% CI 0·56-0·96; p=0·024). Median overall survival was 54·3 months (95% CI 41·9-61·7) with HIPEC versus 45·8 months (38·9-54·2) without. Grade 3 or worse adverse events within 60 days after surgery occurred in 102 (49%) of 207 patients receiving HIPEC versus 56 (27%) of 208 receiving no HIPEC, the most common being anaemia (47 [23%] vs 30 [14%]), hepatotoxicity (23 [11%] vs 18 [9%]), electrolyte disturbance (28 [14%] vs two [1%]), and renal failure (20 [10%] vs three [1%]). There were three deaths within 60 days of surgery, all in the no-HIPEC group.

INTERPRETATION: Adding HIPEC to cytoreductive surgery after response to platinum-based chemotherapy at first epithelial ovarian cancer recurrence significantly improved overall survival. When treating patients with late first relapse of high-grade serous or high-grade endometrioid ovarian cancer amenable to complete cytoreductive surgery at specialist centres, platinum-based HIPEC should be considered to extend overall survival.

FUNDING: French National Cancer Institute and French League Against Cancer.