Session: MP69: Bladder Cancer: Upper Tract Transitional Cell Carcinoma I
MP69-12: The Prediction of Renal Function Change after Unilateral Nephroureterectomy in Upper Tract Urothelial Carcinoma Patients by using Tc-99m MAG3 Renal Scan
Introduction: Radical nephroureterectomy with bladder cuff excision (RNU BCE) is the standard of treatment for high-risk upper tract urothelial carcinoma (UTUC). We aim to develop a predictive equation for post-unilateral RNU BCE renal function by using pre-operative renal scintigraphy. Methods: From January 2010 to December 2020, patients diagnosed with UTUC and underwent unilateral RNU BCE in our institute were reviewed. Comprehensive renal function evaluation by technetium-99m mercaptoacetyltriglycine (Tc-99m MAG3) renal scintigraphy was done pre-operatively. Serum creatinine level was recorded pre-operatively, 3 months (3M) and 6 months (6M) post-operatively (OP). Pearson’s linear correlation analysis was used for developing predictive equation. Internal validation with patients of the same criteria recruited after the study period (2021’s database) was done to test the equation’s accuracy. Cisplatin ineligibility by renal function was defined as eGFR < 60 ml/min/1.73m2. Results: In total, 487 patients who underwent unilateral RNU BCE for UTUC were included. The median pre-operative total effective renal plasma flow (ERPF) was 241.30 ml/min, and the lesion side accounted for 35.6% of total ERPF. Pre-operative lesion side ERPF ratio was significantly associated to post-operative decrease of eGFR ratio at 3 months (R = 0.613, p < 0.001), and the predictive equation was established as: Post-OP 3M Decrease of eGFR (%)= 0.675 x Lesion Side / Total ERPF Ratio (%) + 0.919. Internal validation with 2021’s database showed high accuracy of prediction in post-OP 3M eGFR decrease (R = 0.896). For the 12 patients that experienced RNU-related cisplatin ineligibility, our predictive equation successfully foresaw such renal function loss in all patients, with a prediction accuracy of 12/12 (100%). Conclusions: We established a predictive equation using pre-operative lesion side ERPF ratio to predict post-operative eGFR loss. Such an equation could accurately predict residual renal function and foresee RNU-related cisplatin ineligibility before unilateral RNU. SOURCE OF Funding: The authors declare that they have no conflicts of interest related to the subject matter or materials discussed in this article.
