External validation of yonsei nomogram predicting chronic kidney disease development after partial nephrectomy: An international, multicenter study.

OBJECTIVE: To externally validate Yonsei nomogram. METHODS: From 2000 through 2018, 3526 consecutive patients underwent on-clamp PN for cT1 renal masses at 23 centers were included. All patients had two kidneys, preoperative eGFR ≥60 ml/min/1.73 m2, and a minimum follow-up of 12 months. New-onset CKD was defined as upgrading from CKD stage I or II into CKD stage ≥III. We obtained the CKD-free progression probabilities at 1, 3, 5, and 10 years for all patients by applying the nomogram found at https://eservices.ksmc.med.sa/ckd/. Thereafter, external validation of Yonsei nomogram for estimating new-onset CKD stage ≥III was assessed by calibration and discrimination analysis. RESULTS AND LIMITATION: Median values of patients' age, tumor size, eGFR and follow-up period were 47 years (IQR: 47-62), 3.3 cm (IQR: 2.5-4.2), 90.5 ml/min/1.73 m2 (IQR: 82.8-98), and 47 months (IQR: 27-65), respectively. A total of 683 patients (19.4%) developed new-onset CKD. The 5-year CKD-free progression rate was 77.9%. Yonsei nomogram demonstrated an AUC of 0.69, 0.72, 0.77, and 0.78 for the prediction of CKD stage ≥III at 1, 3, 5, and 10 years, respectively. The calibration plots at 1, 3, 5, and 10 years showed that the model was well calibrated with calibration slope values of 0.77, 0.83, 0.76, and 0.75, respectively. Retrospective database collection is a limitation of our study. CONCLUSIONS: The largest external validation of Yonsei nomogram showed good calibration properties. The nomogram can provide an accurate estimate of the individual risk of CKD-free progression on long-term follow-up.

Yonsei nomogram: A predictive model of new-onset chronic kidney disease after on-clamp partial nephrectomy in patients with T1 renal tumors.

OBJECTIVES: To develop a predictive nomogram for chronic kidney disease-free survival probability in the long term after partial nephrectomy. METHODS: A retrospective analysis was carried out of 698 patients with T1 renal tumors undergoing partial nephrectomy at a tertiary academic institution. A multivariable Cox regression analysis was carried out based on parameters proven to have an impact on postoperative renal function. Patients with incomplete data, <12 months follow up and preoperative chronic kidney disease stage III or greater were excluded. The study end-points were to identify independent risk factors for new-onset chronic kidney disease development, as well as to construct a predictive model for chronic kidney disease-free survival probability after partial nephrectomy. RESULTS: The median age was 52 years, median tumor size was 2.5 cm and mean warm ischemia time was 28 min. A total of 91 patients (13.1%) developed new-onset chronic kidney disease at a median follow up of 60 months. The chronic kidney disease-free survival rates at 1, 3, 5 and 10 year were 97.1%, 94.4%, 85.3% and 70.6%, respectively. On multivariable Cox regression analysis, age (1.041, P = 0.001), male sex (hazard ratio 1.653, P < 0.001), diabetes mellitus (hazard ratio 1.921, P = 0.046), tumor size (hazard ratio 1.331, P < 0.001) and preoperative estimated glomerular filtration rate (hazard ratio 0.937, P < 0.001) were independent predictors for new-onset chronic kidney disease. The C-index for chronic kidney disease-free survival was 0.853 (95% confidence interval 0.815-0.895). CONCLUSION: We developed a novel nomogram for predicting the 5-year chronic kidney disease-free survival probability after on-clamp partial nephrectomy. This model might have an important role in partial nephrectomy decision-making and follow-up plan after surgery. External validation of our nomogram in a larger cohort of patients should be considered.

Estimated glomerular filtration rate's time to nadir after robot-assisted partial nephrectomy: Predictors and clinical significance on renal functional recovery.

OBJECTIVES: To investigate the impact of postoperative time to nadir of estimated glomerular filtration rate on renal functional changes after robot-assisted partial nephrectomy. METHODS: From 2006 to 2015, 287 patients with renal mass who underwent robot-assisted partial nephrectomy in a referral center were analyzed. The cohort was evaluated based on their time to develop nadir: group 1 (no nadir), group 2 (<48 h) and group 3 (≥48 h). The outcome measures were to evaluate the renal function recovery between groups, risk factors for development of nadir ≥48 h, as well as predictors of chronic kidney disease upstaging. RESULTS: The mean estimated glomerular filtration rate percentage change was the worst in group 3 compared with groups 1 and 2, with 13.8%, -0.67% and 8%, respectively (P < 0.001). Chronic kidney disease upstaging was more common in group 3 compared with the other groups (P < 0.001). Age, tumor size, PADUA score and warm ischemia time were predictors of developing ≥48 h estimated glomerular filtration rate nadir (odds ratio 1.04, P = 0.002; odds ratio 1.43, P < 0.001; odds ratio 1.24, P = 0.018; odds ratio 1.05, P < 0.001), respectively. The 5-year probability of freedom from chronic kidney disease upstaging was lower in group 3 (75.6%) compared with the other groups - 88.1% and 100% (P = 0.003). Time to nadir ≥48 h was a predictor of chronic kidney disease upstaging (odds ratio 3.02, P = 0.022). CONCLUSIONS: A continuous decline in estimated glomerular filtration rate (≥48 h) after partial nephrectomy is associated with increased risk of poor functional recovery overtime. Age, tumor size, PADUA score and warm ischemia time are independent predictors of developing ≥48 h time to nadir of estimated glomerular filtration rate. This higher risk subgroup should be targeted for stricter follow up to allow early detection of future risk of renal functional decline.

Off-Clamp Robot-Assisted Partial Nephrectomy: How Far Shall We Proceed?

BACKGROUND: Off-clamp robot-assisted partial nephrectomy (RAPN) is associated with increased intraoperative blood loss compared with on-clamp technique. Our aim was to demonstrate our surgical technique and to determine which tumors are ideally suited for this technique. METHODS: Sixty-two patients who underwent off-clamp RAPN for renal tumor between 2006 and 2016 were retrospectively analyzed. Increased estimated blood loss (EBL) volume was defined as more than 75 percentile. receiver operating characteristic (ROC) analysis was used to determine exact cut-off tumor size and the preoperative aspects and dimensions used for an anatomical (PADUA) score that are associated with increased EBL. Risk factors for increased EBL >400 mL and chronic kidney disease (CKD) upstaging were evaluated using logistic regression analysis. RESULTS: The median follow-up period was 20 months (interquartile range [IQR]: 12-84). Patient's mean age, mean tumor size, and mean body mass index were 53.5 ± 12.2 years, 2.6 ± 1.5 cm, and 25 ± 4.1 kg/m2, respectively. Median EBL volume was 200 mL (IQR: 100-400). ROC analysis showed that tumor size of 3.2 cm (area under the curve [AUC] = 0.82, P < .001) and PADUA score of 9 (AUC = 0.79, P = .001) were cut-off values for increased EBL >400 mL. Patients with tumor size >3.2 cm had longer operative time (116 versus 163 minutes, P = .002), more EBL (150 versus 575 mL, P < .001), and higher blood transfusion rate (0% versus 18.8%, P = .015), with increased tendency of conversion to radical nephrectomy (0% versus 12.5%, P = .063) compared with tumor size ≤3.2 cm. Overall CKD upstaging was present in 22 patients (35.4%). Multivariable logistic regression analysis showed that EBL >400 mL was the only predictor of CKD upstaging (odds ratio: 6.704, P = .009). CONCLUSIONS: Our study showed that the risk of intraoperative bleeding and transfusion rate during off-clamp RAPN is increased if tumor size >3.2 cm and/or PADUA complexity score ≥9. Moreover, EBL >400 mL was a risk factor of CKD upstaging, despite zero ischemia. Further larger prospective studies are warranted to validate our results.

Prostate-specific antigen 10-20 ng/mL: A predictor of degree of upgrading to ≥8 among patients with biopsy Gleason score 6.

PURPOSE: This study aimed to identify the predictors of upgrading and degree of upgrading among patients who have initial Gleason score (GS) 6 treated with robot-assisted radical prostatectomy (RARP). MATERIALS AND METHODS: A retrospective review of the data of 359 men with an initial biopsy GS 6, localized prostate cancer who underwent RARP between July 2005 to June 2010 was performed. They were grouped into group 1 (nonupgrade) and group 2 (upgraded) based on their prostatectomy specimen GS. Logistic regression analysis of studied cases identified significant predictors of upgrading and the degree of upgrading after RARP. RESULTS: The mean age and prostate-specific antigen (PSA) was 63±7.5 years, 8.9±8.77 ng/mL, respectively. Median follow-up was 59 months (interquartile range, 47-70 months). On multivariable analysis, age, PSA, PSA density and ≥2 cores positive were predictors of upgrading with (odds ratio [OR], 1.03; 95% confidence interval [CI], 1.01-1.06; p=0.003; OR, 1.006; 95% CI, 1.01-1.11; p=0.018; OR, 0.65; 95% CI, 0.43-0.98, p=0.04), respectively. On subanalysis, only PSA level of 10-20 ng/mL is associated with upgrading into GS ≥8. They also had lower biochemical recurrence free survival, cancer specific survival, and overall survival (p≤0.001, p=0.003, and p=0.01, respectively). CONCLUSIONS: Gleason score 6 patients with PSA (10-20 ng/mL) have an increased risk of upgrading to pathologic GS (≥8), subsequently poorer oncological outcome thus require a stricter follow-up. These patients should be carefully counseled in making an optimal treatment decision.

Proctorship and mentoring: Its backbone and application in robotic surgery.

In pursuit of continuing medical education in robotic surgery, several forms of training have been implemented. This variable application of curriculum has brought acquisition of skills in a heterogeneous and unstandardized fashion from different parts of the world. Recently, efforts have been made to provide cost effective and well-structured curricula with the aim of bridging the gap between formal fellowship training and short courses. Proctorship training has been implicated on some curriculum to provide excellent progression during the learning curve while ensuring patient safety.

Robot-assisted partial nephrectomy confers excellent long-term outcomes for the treatment of complex cystic renal tumors: Median follow up of 58 months.

OBJECTIVES: To analyze long-term outcomes of robot-assisted partial nephrectomy for treatment of complex cystic renal tumors. METHODS: We retrospectively analyzed the data of patients who underwent robot-assisted partial nephrectomy for cystic (n = 32) and solid (n = 263) renal masses at Severance Hospital, Seoul, Korea. The primary outcome was assessment of perioperative safety for cystic tumor. Secondary outcomes were evaluation of long-term oncological and functional results. RESULTS: Patients' clinical and demographic characteristics were similar among both groups. The median follow up of cystic and solid masses were 58 and 46 months, respectively. Cystic masses were more likely to have low Fuhrman grade 1 and 2 (P = 0.03), and shorter operative time (P = 0.04) compared with solid masses. There was no statistically significant difference regarding warm ischemia time, estimated blood loss, trifecta achievement, length of hospital stay, complication rates and renal function preservation (P > 0.05) between groups. In the solid group, 12 patients (4.1%) recurred, and six patients (2%) died from metastatic renal cell carcinoma, whereas the patients in the cystic group did not have any local or distance recurrence, and the survival rates were 100%. The 5-year cancer-free survival (P = 0.77), cancer-specific survival (P = 0.65) and overall survival (P = 0.83) rates were similar between the groups. CONCLUSION: Robot-assisted partial nephrectomy appears to be safe and feasible treatment for complex cystic renal masses. It confers excellent long-term oncological outcomes. Robot-assisted partial nephrectomy should be the treatment of choice for complex cysts whenever feasible.

Stratified analysis of 800 Asian patients after robot-assisted radical prostatectomy with a median 64 months of follow up.

OBJECTIVE: To report the 5-year oncological outcomes of robot-assisted radical prostatectomy from the largest series ever reported from Asia. METHODS: A retrospective analysis of 800 Asian patients who were treated with robot-assisted radical prostatectomy from July 2005 to May 2010 in the Department of Urology and Urological Science Institute, Yonsei University College of Medicine, Seoul, Korea was carried out. The primary end-point was to evaluate the biochemical recurrence. The secondary end-point was to show the biochemical recurrence-free survival, metastasis-free survival and cancer-specific survival. RESULTS: A total of 197 (24.65%), 218 (27.3%), and 385 (48.1%) patients were classified as low-, intermediate- and high-risk patients according to the D'Amico risk stratification risk criteria, respectively. The median follow-up period was 64 months (interquartile range 28-71 months). The overall incidence of positive surgical margin was 36.6%. There was biochemical recurrence in 183 patients (22.9%), 38 patients (4.8%) developed distant metastasis and 24 patients (3%) died from prostate cancer. Actuarial biochemical recurrence-free survival, metastasis-free survival, and cancer-specific survival rates at 5 years were 76.4%, 94.6% and 96.7%, respectively. Positive lymph node was associated with lower 5-year biochemical recurrence-free survival (9.1%), cancer-specific survival (75.7%) and metastasis-free survival (61.9%) rates (P < 0.001). On multivariable analysis, among all the predictors, positive lymph node was the strongest predictor of biochemical recurrence, cancer-specific survival and metastasis-free survival (P < 0.001). CONCLUSIONS: Herein we report the largest robot-assisted radical prostatectomy series from Asia. Robot-assisted radical prostatectomy is confirmed to be an oncologically safe procedure that is able to provide effective 5-year cancer control, even in patients with high-risk disease.

Simultaneous Retzius-sparing robot-assisted radical prostatectomy and partial nephrectomy.

We present a 61-year-old man who was diagnosed with synchronous prostate cancer and suspicious renal cell carcinoma of the right kidney, treated with combined Retzius-sparing robot-assisted radical prostatectomy (RS-RARP) and robot-assisted partial nephrectomy (RAPN). The combined approach using RS-RARP and RAPN is technically feasible and safe surgical option for treatment of concomitant prostate cancer and suspicious renal cell carcinoma.

The effectiveness and safety of percutaneous nephrolithotomy (PCNL) for solitary kidneys: A single-center experience

OBJECTIVE: To evaluate the outcomes of percutaneous nephrolithotomy in patients with solitary kidneys. METHODOLOGY: Between January 2009 and December 2013, 31 patients with renal stones in solitary kidneys were treated with PCNL. All stones were diagnosed using an unenhanced CT scan. The solitary functioning status of the kidney was congenital absence of the contralateral kidney in 7(22%); opposite nephrectomy in 15(48%); and nonfunctional contralateral kidneys in 9(29%) as detected by nuclear scintigraphy. The serum creatinine and hemoglobin were monitored at regular intervals. The stones were classified using the Guy Stone Score while the complications were analyzed using the Clavien-Dindo Grading System. The mean follow-up in months was 21.3±12.26 (4-48). RESULTS: The male to female ratio is 1.2:1. According to the Guy Stone Score, the stones were Grade 1 in 54.8% (17/31), Grade 2 in 16.1% (5/31), Grade 3 in 6.4% (2/31) and Grade 4 in 22.5% patients, respectively. The stone-free status was determined with a postop CT scan. Complete stone clearance was achieved in 90.3% (28/31) after a single session of PCNL. The mean operative time was 151±36.7(90-230) minutes. According to the Clavien-Dindo Classification, 19 (59.3%) had no complication, 4 (12.9%) had Grade 1 (fever), 7 (29.2%) had Grade 2 (blood transfusion) and 1(3%) had Grade 5 (postoperative hemodialysis, sepsis and death). The rest had stable or improved renal function without postoperative hemodialysis. The mean rise in serum creatinine was 0.67±1.01 (0.1-3.5) mg/dL. Mean drop in hemoglobin was 1.6±0.89(0.5-3.8) gm/dL. CONCLUSION: PCNL is effective and safe for patients with nephrolithiasis in solitary kidneys. This minimally invasive procedure achieves a high stone clearance rate with acceptably low morbidity and mortality.