Jitao Wu1, Chalairat Suk-Ouichai2, Wen Dong3, Zhiling Zhang4, Hajime Tanaka5, Yanbo Wang6, Elvis Caraballo7, Erick M Remer8, Jianbo Li9, Sudhir Isharwal7, Robert Abouassaly7, Steven C Campbell10. 1. Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, OH, USA; Department of Urology, Yantai Yuhuangding Hospital, Yantai, Shandong, China. 2. Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, OH, USA; Division of Urology, Department of Surgery, Siriraj Hospital, Mahidol University, Bangkok, Thailand. 3. Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, OH, USA; Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Department of Urology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, China. 4. Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, OH, USA; Department of Urology, Sun Yat-Sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, China. 5. Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, OH, USA; Department of Urology, Tokyo Medical and Dental University, Tokyo, Japan. 6. Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, OH, USA; Department of Urology, First Hospital of Jilin University, Changchun, China. 7. Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, OH, USA. 8. Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, OH, USA; Imaging Institute, Cleveland Clinic, Cleveland, OH, USA. 9. Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, OH, USA; Department of Quantitative Health Sciences, Cleveland Clinic, Cleveland, OH, USA. 10. Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, OH, USA. Electronic address: campbes3@ccf.org.
Abstract
BACKGROUND: Percentage parenchymal mass preserved (PPMP) is a key determinant of functional outcomes after partial nephrectomy (PN); however, predictors of PPMP have not been defined. OBJECTIVE: To provide a comprehensive analysis of the functional impact of and potential predictive factors for PPMP. DESIGN, SETTING, AND PARTICIPANTS: We analyzed data for 464 patients managed with PN at our center with necessary studies to determine vascularized parenchymal mass and function preserved within the operated kidney. PPMP was measured from computed tomography scans <2 mo before and 3-12 mo after PN. INTERVENTION: PN. OUTCOME MEASUREMENTS/STATISTICAL ANALYSIS: Recovery from ischemia was defined as percentage ipsilateral glomerular filtration rate (GFR) preserved normalized by PPMP. We used Pearson correlation to evaluate the relationships between GFR preserved and PPMP. Multivariable logistic regression was used to assess predictors of PPMP. RESULT AND LIMITATIONS: Ninety-six patients (21%) had a solitary kidney. The median tumor size and RENAL score were 3.5cm and 8, respectively. Cold/warm ischemia were utilized in 183/281 patients for which the median ischemia time were 28/20min. The median preoperative and postoperative vascularized parenchymal mass in the operated kidney were 194 and 157cm3, respectively, resulting in median PPMP of 84%. GFR preservation correlated strongly with PPMP (r=0.64; p<0.001). Recovery from ischemia was suboptimal (<80%) in 71 patients (15%), while suboptimal PPMP (<80%) was a more common adverse event, occurring in 160 patients (34%; p<0.001). Multivariable analysis demonstrated that greater tumor size and complexity were associated with lower PPMP (p≤0.04), while solitary kidney and hypothermia were associated with higher PPMP (p<0.001). Longer ischemia time was also associated with lower PPMP (p=0.003), probably reflecting the complexity of the surgery. Limitations include the retrospective design. CONCLUSION: PPMP correlates strongly with functional outcomes after PN, and lower PPMP is the most common and important source of functional decline after PN. Larger tumors, greater tumor complexity, and prolonged ischemia time were associated with lower PPMP, while PPMP tended to be greater for solitary kidneys, confirming that PPMP is a modifiable factor. PATIENT SUMMARY: Kidney function after partial nephrectomy primarily depends on the amount of vascularized kidney preserved by the procedure. Lower recovery of function is seen when operating on larger tumors in unfavorable locations, but preservation of the parenchymal mass can be improved when truly necessary, such as when operating on a tumor in a solitary kidney.
BACKGROUND: Percentage parenchymal mass preserved (PPMP) is a key determinant of functional outcomes after partial nephrectomy (PN); however, predictors of PPMP have not been defined. OBJECTIVE: To provide a comprehensive analysis of the functional impact of and potential predictive factors for PPMP. DESIGN, SETTING, AND PARTICIPANTS: We analyzed data for 464 patients managed with PN at our center with necessary studies to determine vascularized parenchymal mass and function preserved within the operated kidney. PPMP was measured from computed tomography scans <2 mo before and 3-12 mo after PN. INTERVENTION: PN. OUTCOME MEASUREMENTS/STATISTICAL ANALYSIS: Recovery from ischemia was defined as percentage ipsilateral glomerular filtration rate (GFR) preserved normalized by PPMP. We used Pearson correlation to evaluate the relationships between GFR preserved and PPMP. Multivariable logistic regression was used to assess predictors of PPMP. RESULT AND LIMITATIONS: Ninety-six patients (21%) had a solitary kidney. The median tumor size and RENAL score were 3.5cm and 8, respectively. Cold/warm ischemia were utilized in 183/281 patients for which the median ischemia time were 28/20min. The median preoperative and postoperative vascularized parenchymal mass in the operated kidney were 194 and 157cm3, respectively, resulting in median PPMP of 84%. GFR preservation correlated strongly with PPMP (r=0.64; p<0.001). Recovery from ischemia was suboptimal (<80%) in 71 patients (15%), while suboptimal PPMP (<80%) was a more common adverse event, occurring in 160 patients (34%; p<0.001). Multivariable analysis demonstrated that greater tumor size and complexity were associated with lower PPMP (p≤0.04), while solitary kidney and hypothermia were associated with higher PPMP (p<0.001). Longer ischemia time was also associated with lower PPMP (p=0.003), probably reflecting the complexity of the surgery. Limitations include the retrospective design. CONCLUSION:PPMP correlates strongly with functional outcomes after PN, and lower PPMP is the most common and important source of functional decline after PN. Larger tumors, greater tumor complexity, and prolonged ischemia time were associated with lower PPMP, while PPMP tended to be greater for solitary kidneys, confirming that PPMP is a modifiable factor. PATIENT SUMMARY: Kidney function after partial nephrectomy primarily depends on the amount of vascularized kidney preserved by the procedure. Lower recovery of function is seen when operating on larger tumors in unfavorable locations, but preservation of the parenchymal mass can be improved when truly necessary, such as when operating on a tumor in a solitary kidney.
Authors: Fabio Crocerossa; Cristian Fiori; Umberto Capitanio; Andrea Minervini; Umberto Carbonara; Savio D Pandolfo; Davide Loizzo; Daniel D Eun; Alessandro Larcher; Andrea Mari; Antonio Andrea Grosso; Fabrizio Di Maida; Lance J Hampton; Francesco Cantiello; Rocco Damiano; Francesco Porpiglia; Riccardo Autorino Journal: Eur Urol Open Sci Date: 2022-03-03