4:03 PM Abstract No. 271 Risk stratification of periprocedural complications and treatment failure for T1b renal cell carcinoma

Abstract

To investigate the clinical utility of the RENAL nephrometry scoring system (which incorporates tumor Radius, Exophytic or endophytic location, Nearness to renal collecting system or sinus, Anterior or posterior location, and Location relative to polar lines) for prediction of complications and local recurrence in T1b renal cell carcinoma (RCC) following thermal ablation. A retrospective evaluation of 83 patients (M:F = 71:12, mean age =77 years) was performed between December 2008 and October 2019. T1b is defined as a biopsy-proven RCC that is between 4 and 7 cm in diameter. The RENAL scores were calculated based on the tumor morphology seen on imaging, through which tumors were stratified into high risk (RENAL = 10-12), moderate risk (RENAL = 7-9), and low risk (RENAL = 4-6) groups. The rates of residual disease and local recurrence were compared among the three groups. Of the 68 biopsy-proven T1b RCC (mean RENAL score, 7.7, SD =1.8) that were treated with percutaneous CT-guided thermal ablation, 30/79 (38%) had high RENAL scores, 30/79 (38%) had moderate RENAL scores, and 19/79 (24%) had low RENAL scores. High RENAL score was associated with a significantly elevated risk of hematoma (40%), compared to the moderate (29%) and low (10%) RENAL score groups (P = 0.0001). Similarly, a high RENAL score is associated with a significant rate of ureter injury (10%), which was not observed in the moderate and low RENAL score groups (both 0%). Local recurrence was also more prevalent in the high RENAL score group (20%) compared to the moderate (10%) and low (0%) RENAL score groups (P = 0.0001). The RENAL nephrometry scoring system is a very attractive tool for predicting the rates of complications and treatment failure in patients undergoing thermal ablation for T1b RCC. This scoring system could allow interventional radiologists and their patients to better prepare for the unique risks of complications and outcomes conferred by each tumor’s unique RENAL score.Tabled 1Analysis of Periprocedural Complications and Treatment Failure based on RENAL Nephrometry ScoreHigh RENAL RiskModerate RENAL RiskLow RENAL RiskPHematoma Yes12 (40%)9 (30%)2 (10%)0.001 No18 (60%)22 (70%)17 (90%)Ureter Injury Yes3 (10%)0 (0%)0 (0%)0.001 No27 (90%)31 (100%)9 (100%)Residual disease Yes10 (33%)3 (10%)2 (10%)0.001 No20 (67%)28 (90%)17 (90%)Local recurrence Yes6 (20%)3 (10%)0 (0%)0.001 No24 (80%)28 (90%)19 (100%) Open table in a new tab