Acute kidney injury after cytoreductive surgery and HIPEC: incidence and timing in a 10-year single-center cohort

Introduction Cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) is used for selected peritoneal malignancies but carries substantial perioperative physiological stress. Acute kidney injury (AKI) is clinically relevant, yet data on its incidence and postoperative timing remain heterogeneous.Methods We performed a retrospective single-center cohort study of consecutive adults undergoing CRS-HIPEC between 2014 and 2024. AKI was defined using KDIGO serum creatinine criteria assessed from postoperative day (POD) 1 to POD 5. Baseline, oncologic and treatment related variables were compared according to AKI status. Exploratory multivariable logistic regression assessed associations between routinely available variables and postoperative AKI. Secondary outcomes included length of stay and exploratory overall survival.Results Among 308 cases, AKI occurred in 70 cases (22.7%). Stage 1 AKI occurred in 45 cases (14.6%), stage 2 in 18 cases (5.8%) and stage 3 in 7 cases (2.3%). Renal replacement therapy was required in 2 cases (0.6%). Peak serum creatinine occurred on POD 1 to POD 2 in 64.3% of cases, while 35.7% peaked on POD 3 to POD 5. Median length of stay was 7.5 days [IQR 6.5 to 9.6] in the AKI group and 7.4 days [IQR 6.5 to 8.8] in the non-AKI group (p = 0.0998). In exploratory multivariable analysis, no included variable was significantly associated with AKI; PCI showed a non-significant association (OR 1.04 per point, p = 0.11).Conclusions AKI was frequent after CRS-HIPEC, and more than one third of cases peaked beyond the first 48 h. These findings support postoperative renal surveillance through POD 5.