Hyperthermic Intraperitoneal Chemotherapy in the Treatment Armamentarium of Epithelial Ovarian Cancer: Time to End the Dichotomy

<b><i>Background:</i></b> Advanced epithelial ovarian cancer (EOC) is an incurable disease with over 75% of the patients developing recurrence in the peritoneum. Hyperthermic intraperitoneal chemotherapy (HIPEC) is a promising treatment option for both first-line therapy and treatment of recurrence. In this article, we review the rationale and current evidence for performing HIPEC and the role of HIPEC in the light of targeted systemic therapies. <b><i>Summary:</i></b> There are few randomized trials and several retrospective studies on the role of HIPEC in the management of EOC. A 12-month-overall survival (OS) benefit of the addition of HIPEC to interval cytoreductive surgery (CRS) was demonstrated in 1 randomized trial following which HIPEC has been included as a treatment option for this indication in several national/international guidelines. One retrospective propensity score-matched analysis showed a 16-month OS benefit of adding HIPEC to primary CRS. One randomized trial showed no benefit of the addition of carboplatin HIPEC to secondary CRS over secondary CRS alone. For patients undergoing primary CRS and secondary CRS for recurrence, the results of ongoing randomized trials are needed to define the role of HIPEC in these situations. All clinical trials have shown that the morbidity of HIPEC performed after CRS is acceptable. Along with the emergence of HIPEC as a promising surgical therapy, targeted therapies like bevacizumab and poly adenosine diphosphate-ribose polymerase inhibitors have been developed that have shown a survival benefit in selected patients. In principle, HIPEC and targeted therapies work in different ways and it is plausible to assume that their benefit could be additive, and their combination should be evaluated in clinical trials. The impact of prognostic factors like the disease extent, pathological response to systemic chemotherapy (SC), the histological subtype and molecular profile on the benefit of HIPEC, and targeted therapies has not been evaluated in clinical trials. <b><i>Key Messages:</i></b> HIPEC is an important therapeutic strategy in the treatment of EOC. While its role in patients undergoing interval CRS has been established, the results of ongoing randomized trials are needed to define its benefit at other time points. The morbidity of HIPEC in addition to CRS is acceptable. More research is needed to define subgroups that benefit most from HIPEC based on the extent of disease, response to SC, histology, and molecular profile. The combination of HIPEC and maintenance therapies should be evaluated in well-designed randomized clinical trials that evaluate not just the survival benefit and morbidity but also the cost-effectiveness of each therapy.