Renal Cell Carcinoma: Comparison of RENAL Nephrometry and PADUA Scores with Maximum Tumor Diameter for Prediction of Local Recurrence after Thermal Ablation

Abstract

Purpose To evaluate the performance of the radius, exophytic or endophytic, nearness to collecting system or sinus, anterior or posterior, and location relative to polar lines (RENAL) nephrometry and preoperative aspects and dimensions used for anatomic classification (PADUA) scoring systems and other tumor biometrics for prediction of local tumor recurrence in patients with renal cell carcinoma after thermal ablation. Materials and Methods This HIPAA-compliant study was performed with a waiver of informed consent after institutional review board approval was obtained. A retrospective evaluation of 207 consecutive patients (131 men, 76 women; mean age, 71.9 years ± 10.9) with 217 biopsy-proven renal cell carcinoma tumors treated with thermal ablation was conducted. Serial postablation computed tomography (CT) or magnetic resonance (MR) imaging was used to evaluate for local tumor recurrence. For each tumor, RENAL nephrometry and PADUA scores were calculated by using imaging-derived tumor morphologic data. Several additional tumor biometrics and combinations thereof were also measured, including maximum tumor diameter. The Harrell C index and hazard regression techniques were used to quantify associations with local tumor recurrence. Results The RENAL (hazard ratio, 1.43; P = .003) and PADUA (hazard ratio, 1.80; P< .0001) scores were found to be significantly associated with recurrence when regression techniques were used but demonstrated only poor to fair discrimination according to Harrell C index results (C, 0.68 and 0.75, respectively). Maximum tumor diameter showed the highest discriminatory strength of any individual variable evaluated (C, 0.81) and was also significantly predictive when regression techniques were used (hazard ratio, 2.98; P < .0001). For every 1-cm increase in diameter, the estimated rate of recurrence risk increased by 198%. Conclusion Maximum tumor diameter demonstrates superior performance relative to existing tumor scoring systems and other evaluated biometrics for prediction of local tumor recurrence after renal cell carcinoma ablation. RSNA, 2016.

Local recurrence and other oncologic outcomes after percutaneous image-guided tumor ablations on stageT1b renal cell carcinoma: a systematic review and network meta-analysis

“…Katsanos et al [33] and Rivero et al [34] have published meta-analyses on T1 RCC comparing ablation to surgery concluding that ablative therapies are associated with a lower complication rate and cause less of a decrease in eGFR compared with PN. These meta-analyses concerned all cT1 renal masses [35] without segregating T1a from T1b. More recently, Yu et al [36] found that there were no significant differences regarding oncologic outcomes and complications between percutaneous microwave ablation and laparoscopic partial nephrectomy for patients with cT1a renal cell carcinoma.…”

Systematic Review of Contemporary Evidence for the Management of T1 Renal Cell Carcinoma: What IRs Need to Know for Kidney Cancer Tumor Boards

“…88 Another study, which included 207 patients treated with TA, proposes that maximum tumor diameter is superior to scoring systems in the prediction of local recurrence following ablation. 89 As TA outcomes continue to improve with comparable outcomes to PN, cost will likely play a larger role in the management of small RCCs. 90 A systematic review and meta-analysis identified six articles published from 2008 to 2013 that evaluated cost for the management of small renal masses.…”

Association among the R.E.N.A.L. nephrometry score and clinical outcomes in patients with small renal masses treated with percutaneous contrast enhanced ultrasound radiofrequency ablation

“…These differences may be explained by the lack of a high complexity group in our study whereas the Camacho et al study had 61 low, 26 medium and 14 high patients regarding the RNS and the Schmit et al study had 351, 330 and 70 low, medium and high complexity cases respectively. On the other hand, Maxwell et al studied 217 biopsy-proven SRMs treated mainly with CT guided percutaneous RFA reporting that maximum tumor diameter was the strongest predictor of local recurrence with a Harrell C index = 0.81 while RNS was found to be significantly predictive but showing poor performance with a Harrell C index = 0.68, limiting its overall utility in the authors’ opinion [29]. Neither pathology report nor subtype of RCC were associated with recurrence nor mortality, which is consistent with previous research, finding that 64–84% of SRM are indolent tumors.…”