Category: Laparoscopic/ Robotic: Other

MP25-12 - Predicting renal function after Partial Nephrectomy: Development and Internal Validation of a Nomogram

Sun, Sep 23
10:00 AM - 12:00 PM

Introduction & Objective :

Loss of renal function is a clinical impacting event after partial nephrectomy (PN).

We aimed to create a model to predict loss of renal function in patients undergoing PN.

Methods :

A total of 1897 patients who underwent PN with warm ischemia technique between 2008 and 2017 were extracted from the Institutional database. Loss of renal function was defined by Chronic Kidney Disease (CKD) upstaging based on 3rd month postoperatively eGFR.

A nomogram was built based on the final multivariable model. Interval validation and calibration of the model was performed using the receiver operator curve (ROC) with 1000 bootstrap replications, graphic plotting observed incidence versus nomogram predicted probability, and the extreme training vs test procedure known as the leave-one-out cross-validation (LOOCV). 

Results :

Overall, postoperative CKD upstaging at third month occurred in 474 patients (25%). On multivariable analysis, age, sex, baseline eGFR categorized by CKD stages and ischemia time were identified as predictors for the outcome of interest (all p-values ≤ 0.03). Body Mass Index and RENAL nephrometry score were included in the nomogram for the clinical and statistical relevance (p = 0.1). Final nomogram is reported in Figure 1.Validation methods used were similar in the results: LOOCV had accuracy = 0.72; Receiver Operating Characteristiccurve had Area Under Curve (AUC) = 0.755 (95% CI: 0.717-0.797; the logistic nomogram model had a c-index of 0.76; the calibration plot had a concordance coefficient of 0.97 (95% CI: 0.91-0.99) (Figure 2)

Conclusions :

To the best of our knowledge, this is the first nomogram for the early prediction of postoperative CKD upstaging in patients undergoing PN. The strength of the study is the large sample size used to validate it. 

Riccardo Bertolo

Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, OH, USA
Turin, Piemonte, Italy

Riccardo Bertolo, MD
Research Fellow, Robotic Urology,
Cleveland Clinic, Cleveland, OH, USA
PhD Candidate, Bioengineering in Medical/Surgical Sciences
Turin Politechnic, Italy

Juan Garisto

Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, OH, USA
Cleveland, Ohio

Juan Garisto, MD is an Advanced Laparoscopy & Robotics clinical fellow at Cleveland Clinic, Cleveland, OH, United States under the mentorship of Dr. Jihad Kaouk. He completed a Society of Urologic Oncology fellowship at the University of Toronto and did his urology residency training at Complejo Hospitalario Dr. A.A.Madrid in Panama City, Panama.

His current research interest in single port surgery and multidisciplinary management of urologic malignancies, in particular kidney and bladder cancer.

Jianbo Li

Cleveland, Ohio

Julien Dagenais

Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, OH, USA
Cleveland, Ohio

Jihad Kaouk

Professor and Director, Center for Robotic and Image Guided Surgery Vice Chair, Surgical Innovations
Glickman Urologic Institute, Cleveland Clinic
Cleveland, Ohio

Jihad Kaouk, MD FACS

Dr. Jihad Kaouk is an American Board certified Urologist and Director, Center of Robotic and Image Guided Surgery at the Cleveland Clinic Glickman Urological Institute. He also serves as Professor of Surgery at the Cleveland Clinic Lerner College of Medicine, Vice Chair for Surgical Innovations and chair holder for the Zegarac-Pollock Endowed Chair in laparoscopic and robotic surgery.
In Innovations, he has performed several first ever done surgical procedures, including the first Robotic single port surgery through the belly button in 2008, the first completely transvaginal kidney removal in 2009, and the first robotic perineal prostatectomy in 2014 Dr. Kaouk holds 2 USA patents for medical devices used during partial nephrectomy and in robotic surgery.

Since 2005, Dr. Kaouk has served on committees at the national and local levels. From 2005-2008, he served in the American Urological Association’s Urologic Diagnostic and Therapeutic Imaging Task Force, from 2006-2010 he was on the Guidelines for the Management of small Renal Masses committee. Currently Dr Kaouk serves as Chairman elect on the AUA New Technology and Imaging committee, and is President Elect of (SURS) Society of Urologic Robotic Surgery. Dr Kaouk is associate editor of Urology journal.

Dr Kaouk have lectured in 130 scientific meetings, chaired 24 urologic meeting and performed live surgery in 18 medical centers worldwide. He authored 460 peer reviewed scientific publication, 26 book chapters and hundreds of scientific abstracts and surgical movies. Dr Kaouk received 32 honors and awards including Cleveland clinic innovator award twice, Teacher of the Year award, and EndoUrology 2017 Best Fellowship Program Director Award.

Presently, Dr Kaouk holds membership with the American Urological Association, the Endourological Society, Society of Urologic Oncology, Society of Robotic Surgery, and the Lebanese Order of Physicians. He is a fellow of the American college of Surgeons.