Toxicity is a concern with HIPEC.5 Cytoreductive surgery for ovarian cancer can be associated with substantial morbidity, and exposing patients to prolonged operative time, extended periods of hyperthermia, and high doses of cytotoxic agents is a concern. When performed by high volume, experienced practitioners, approximately 12% of patients experience serious (grade 3-5) toxicity after CRS with HIPEC, with a procedure-related mortality of 1.2%. The majority of major toxicities were bone marrow suppression and nephrotoxicity (which in some cases can result in patients requiring hemodialysis in the immediate postoperative period). It is for this reason that most HIPEC protocols include a routine ICU admission postoperatively to closely monitor patients for major renal toxicity and electrolyte disturbances. These complications are associated with higher doses of administered cisplatin. Febrile neutropenia and gastrointestinal complications (such as bowel perforation, fistula, or anastomotic leak) also comprise the most common major toxicities. Patient factors to consider as higher risk for morbidity and mortality include underlying cardiac or pulmonary disease, poor performance status, extreme obesity, and preexisting renal disease.
While the history of HIPEC was focused around the treatment of GI peritoneal malignancies, in more recent years, the technique has been applied and studied in women with ovarian cancer.
The indications for use can vary from the upfront setting (at the time of primary CRS), following neoadjuvant chemotherapy (at the time of interval CRS), or in the recurrent setting (at the time of secondary CRS).2 Possibly the most compelling study exploring HIPEC in ovarian cancer was published earlier this year in the New England Journal of Medicine.6 This study explored the use of HIPEC at the time of interval CRS following three cycles of neoadjuvant platinum and taxane intravenous chemotherapy. Two hundred and forty-five patients were randomly assigned at the time of optimal interval CRS to either CRS alone or CRS with HIPEC with cisplatin administered over 90 minutes. All patients received three additional cycles of intravenous platinum and taxane chemotherapy. Death was observed in a significantly higher proportion of patients in the non-HIPEC group (62% versus 50%). HIPEC was associated with a hazard ratio for death of 0.67 (P = .02). In this study, a similar number of severe adverse outcomes were observed in the two groups, though specific information was lacking, particularly with respect to renal toxicity.
These findings are intriguing and have energized interest in HIPEC by many gynecologic oncology providers; however, there are some concerns regarding the results. Patients in this study received not one intervention, but in fact three interventions (hyperthermia, an additional cycle of chemotherapy, and the peritoneal administration of chemotherapy). Any one of these three variables could explain the outcomes and it is difficult to know if all three (in the form of HIPEC) are necessary to see this observed benefit. Others have questioned the finding of no added toxicity when HIPEC is applied. This is inconsistent with what has been presented elsewhere. It is unclear from the data whether or not the nephrotoxicity was comparable between the two groups or more severe among those who received HIPEC.
An additional concern regarding HIPEC is the feasibility. Additional operative times (by up to 90 minutes), increased duration of hospitalization (including ICU admission), and additional equipment and specialized personnel are required for this technique. This may further hinder its uptake and routine practice. In the meantime, we continue to await further clinical trials that will better define the ovarian cancer patient population who might benefit from this technique and provide further data regarding its risk/benefit profile.