OBJECTIVEThe objective of this research is to compare the ability of mFI5 to the mFI11 to predict frailty, postoperative complications, discharge location for patients with ovarian cancer undergoing hyperthermic intraperitoneal chemotherapy (HIPEC) at time of cytoreductive surgery.METHODSThis is a single-institution retrospective study in patients with advanced (Stage III, IV) or recurrent ovarian cancer treated with surgical cytoreduction with HIPEC. Logistic regression was used to evaluate frailty as well as factors associated with moderate to severe Accordion postoperative complications and discharge to home. Correlation was calculated between mFI5 and mFI11.RESULTSOf 141 patients who received HIPEC between 2010 and 2020, 23 patients were classified as frail (mFI5 score ≥2), while 118 were not frail. Frail patients were significantly older with mean age 65.9 compared to non-frail patients who had mean age of 59.1 (p = 0.005), as well as a higher Charlston Comorbidity Index (p < 0.001), and more renal disease (p = 0.025), hypothyroidism (p = 0.005), and hyperlipidemia (p = 0.004). mFI5 and mFI11 scores for frailty were highly correlated (spearman rho 0.98, p < 0.001). Frail patients were more likely to be discharged to a skilled nursing facility (22.7 %) vs. 6.8 % of non-frail patients, or require home services (18.2 % vs 8.5 %, p = 0.025). On multivariable logistic regression, frail patients were more likely to experience moderate or higher Accordion postoperative complications (OR 3.08, p = 0.024).CONCLUSIONSThe mFI5, a simpler tool than the mFI11, is also highly associated with postoperative complications and need for postoperative services in patients with ovarian cancer undergoing HIPEC at time of cytoreductive surgery.