Current status of hyperthermic intraperitoneal chemotherapy (HIPEC) for ovarian cancer in the United States

Objectives: 1.) To compare frequency of HIPEC use in ovarian cancer treatment before and after publication of the phase III study by van Driel et al. in January 2018. 2.) To compare associated rates of hospital-based outcomes, including length of stay, intensive care unit (ICU) admission, complications, and costs in ovarian cancer surgery with or without HIPEC. Methods: We queried Vizient's administrative claims database of 550 US hospitals for ovarian cancer surgeries from January 2016–January 2020 using ICD-10 diagnosis and procedure codes. Sodium thiosulfate administration was used to identify HIPEC cases according to the published protocol. Student t-tests and relative risk (RR) were used to compare continuous variables and contingency tables, respectively. Results: 152 ovarian cancer patients had HIPEC at 39 hospitals, and 20,014 ovarian cancer patients had surgery without HIPEC at 256 hospitals. Following the trial publication, 97% of HIPEC cases occurred. During the index admission, HIPEC patients had longer median length of stay (8.4 vs. 5.7 days, p < 0.001) and higher percentage of ICU admissions (63.1% vs. 11.0%, p < 0.001) and complication rates (RR = 1.87, p = 0.002). Index admission direct costs ($21,825 vs. $12,038, p < 0.001) and direct cost index (observed/expected costs) (1.87 vs. 1.11, p < 0.001) were also greater in the HIPEC patients. No inpatient deaths or 30-day readmissions were identified after HIPEC. Conclusions: Use of HIPEC for ovarian cancer increased in the US after publication of a phase III clinical trial in a high-impact journal, though the absolute number of cases remains modest. Incorporation of HIPEC was associated with increased cost, hospital length of stay, ICU admission, and hospital-acquired complication rates. Further studies are needed in order to evaluate long-term outcomes, including morbidity and survival.