Real-world use and outcomes of hyperthermic intra-peritoneal chemotherapy for stage III ovarian cancer.

OBJECTIVE

OVHIPEC-1 demonstrated improved survival with adding hyperthermic intra-peritoneal chemotherapy (HIPEC) to interval cytoreductive surgery in patients with stage III epithelial ovarian cancer. Following these findings, HIPEC was incorporated into Dutch national guidelines in 2019. This study evaluated HIPEC use and its impact on outcomes in routine clinical practice in The Netherlands.

METHODS

This nationwide, population-based study included all Dutch patients with stage III ovarian cancer who underwent complete or optimal interval cytoreductive surgery between 2020 and 2021. We evaluated HIPEC use and analyzed associations with patient characteristics, early post-operative outcomes, and overall survival. Multi-variable logistic, linear, and Cox regression models were used with multiple imputation and adjustment for key prognostic factors, including cytoreduction outcome and histological subtype. Adjusted overall survival was estimated using inverse probability of treatment weighting.

RESULTS

The study included 473 patients. HIPEC use increased from 56% in 2020 to 63% in 2021. Patients receiving HIPEC were generally younger, had better performance status, stage IIIC disease, and more often achieved complete cytoreduction. Bowel surgery with stoma creation was more common among HIPEC patients. After adjusting for important prognostic factors, median hospital stay was longer for the HIPEC group than the cytoreductive surgery-only (7 [interquartile range {IQR} 6-9] vs 6 days [IQR 5-8], p < .0001), with no significant difference in post-operative complications or start of adjuvant chemotherapy. HIPEC was associated with significantly improved overall survival compared to surgery-only (adjusted 3-year overall survival; 62% (95% confidence interval [CI] 53 to 72) vs 51% (95% CI 42 to 61), adjusted hazard ratio 0.69, 95% CI 0.48 to 0.99, p=.044).

CONCLUSIONS

Following its inclusion in Dutch national guidelines, HIPEC was administered to 63% of eligible patients by 2021. The effects of HIPEC on early post-operative outcomes and overall survival align with those reported in randomized trials. These findings support the effectiveness and safety of HIPEC in clinical practice and its integration into in stage III ovarian cancer treatment protocols.