ORLANDO, FL USA (UroToday.com) - The Renal Pelvic Score (RPS) is a novel scoring system that can be used to classify renal pelvis anatomy. A line is drawn connecting the two polar lines on excretory phase images, and each pelvis is assigned an RPS based on the percentage of renal pelvis area (by linear dimension) contained inside the volume of the renal parenchyma. Each pelvis is then classified as “intra”-renal (RPS > 50%) or “extra”-renal (RPS < 50%). Dr. Bic Cung presented a single-institution validation study of the RPS.
A prospective institutional RCC database was utilized to identify all patients undergoing partial nephrectomy (PN) for localized RCC from 2007−2013. Patients were classified by RPS as having an intra or extraparenchymal renal pelvis, and multivariate logistic regression models were used to examine the relationship between RPS and urine leak.
Among 831 patients treated with partial nephrectomy (57.3% robotic), 54 (6.5%) patients developed a clinically significant or radiographically-identified urine leak. Intrarenal pelvic anatomy was associated with a markedly increased risk of urine leak (43.1% vs 3.0%; p < 0.001), major urine leak requiring intervention (23.6% vs 1.7%; p < 0.001), and minor urine leak (19.4% vs 1.2%; p < 0.001) compared to patients with an extrarenal pelvis. Following multivariable adjustment, RPS (intraparenchymal renal pelvis) was the most predictive of urine leak as was the tumor endophyticity (“E” score of 3, and intraoperative collecting system entry.
Renal pelvic anatomy, as measured by the RPS, best predicts urine leak following open and robotic partial nephrectomy. Pre-operative identification of patients at increased risk for urine leak should be considered in peri-operative management and counseling algorithms.
Presented by Bic Cung, MD at the American Urological Association (AUA) Annual Meeting - May 16 - 21, 2014 - Orlando, Florida USA
Fox Chase Cancer Center, Philadelphia, PA USA
Written by Jeffrey J.Tomaszewski, MD, medical writer for UroToday.com