Renal tumor and inferior vena cava tumor thrombus (RT-IVCTT) as a unique model for exploring congestive renal injury remains largely unexplored. Chronic kidney disease significantly correlates with postoperative adverse events. Although preoperative renal dysfunction (pre-RD) is frequently observed in RT-IVCTT, the predictors of pre-RD and its impact on surgical outcomes and prognosis remain unclear. This study aimed to evaluate the role of pre-RD as a risk factor for morbidity and mortality and identify the predictors of pre-RD in patients with RT-IVCTT.

208 consecutive postoperative patients with non-distant metastasis RT-IVCTT were enrolled between June 2013 and June 2023. Clinicopathological, operative, and survival data were analyzed to determine a clinically meaningful cutoff for preoperative estimated glomerular filtration rate (pre-eGFR). Multivariate linear, logistic, and Cox regression models were employed.

Subgroup analysis defined pre-RD as pre-eGFR <90 ml/min/1.73m², found in 59 patients (28.4%). Univariate analysis revealed that pre-RD was associated with increased operative time, intraoperative blood transfusion, extended intensive care unit stay, and complications. Pre-RD remained a significant independent risk factor for major postoperative complications in multivariate analysis. Age >56 years, body mass index >24 kg/m², left-sided tumors, and IVC obstruction >75% were independent risk factors for pre-RD. Survival analysis revealed that pre-RD was an independent risk factor for poorer overall survival.

Pre-RD is an independent risk factor for increased rate of major complications and diminished long-term survival after surgery. Hemodynamic changes from IVC obstruction are associated with pre-RD. eGFR-based renal function assessments may improve perioperative management.