Predicting factor analysis of postoperative complications after robot-assisted radical cystectomy: Multicenter KORARC database study.

OBJECTIVES: To evaluate postoperative complications following robot-assisted radical cystectomy in patients diagnosed with bladder cancer and reveal if there are predictors for postoperative complications. METHODS: Prospectively collected medical records of 730 robot-assisted radical cystectomy patients between 2007/04 and 2019/05 in 13 tertiary referral centers were reviewed. Perioperative outcomes were compared between two groups by postoperative complications (complication vs non-complication). We assessed recurrence-free survival, cancer-specific survival, and overall survival between groups. Regression analyses were implemented to identify factors associated with postoperative complications. RESULTS: Any total and high-grade complication (Clavien-Dindo grade ≥3) rates were 57.8% and 21.1%, respectively. Patients in complication group had significantly higher proportion of diabetes mellitus (P = 0.048), chronic kidney disease (P = 0.011), dyslipidemia (P < 0.001), longer operation time (P = 0.001), more estimated blood loss (P = 0.001), and larger intraoperative fluid volume (P < 0.001). There was a significant difference in cancer-specific survival (log-rank P = 0.038, median cancer-specific survival: both groups not reached). Dyslipidemia (odds ratio 2.59, P = 0.002) and intraoperative fluid volume (odds ratio 1.0002, P = 0.040) were significantly associated with high-grade postoperative complications. Diabetes mellitus (odds ratio 1.97, P = 0.028), chronic kidney disease (odds ratio 1.89, P = 0.046), dyslipidemia (odds ratio 5.94, P = 0.007), and intraoperative fluid volume (odds ratio 1.0002, P = 0.009) were significantly associated with any postoperative complications. CONCLUSIONS: Patients with diabetes mellitus, chronic kidney disease, dyslipidemia, or a relatively large intraoperatively infused fluid volume are more likely to develop postoperative complications. Patients with postoperative complications might have a possibility of lower cancer-specific survival rate.

Oncological outcome according to attainment of pentafecta after robot-assisted radical cystectomy in patients with bladder cancer included in the multicentre KORARC database.

OBJECTIVES: To investigate the oncological significance of a robot-assisted radical cystectomy (RARC)-related pentafecta in patients with bladder cancer. PATIENTS AND METHODS: Using the KORARC database, which includes data from 12 centres, data from 730 patients who underwent RARC between April 2007 and May 2019 were prospectively collected and retrospectively analysed. Pentafecta was achieved if patients met all of the following criteria: (i) negative soft tissue surgical margin; (ii) ≥16 lymph nodes removed; (iii) no major complications (Clavien-Dindo grade 3-5) within 90 days; (iv) no clinical recurrence within the first 12 months; and (v) no ureteroenteric stricture. Patients were divided into two groups according to pentafecta attainment, and a comparison of overall survival (OS) and cancer-specific survival (CSS) using multivariate Cox proportional analysis was then carried out. RESULTS: Of the 730 patients included in this analysis, 208 (28.5%) attained the RARC pentafecta; the remaining 522 (71.5%) did not. The mean age of the patients was 64.67 years, 85.1% were men, 53.6% received a conduit, 37.7% received orthotopic neobladders and the total complication rate was 57.8%. Those who attained the pentafecta received more neobladders (P = 0.039), were more likely to be treated with the intracorporeal technique (P < 0.001), had longer operating times (P = 0.020) and had longer console time (P = 0.021) compared with those who did not attain the pentafecta. Over a mean of 31.1 months of follow-up, the pentafecta attainment group had significantly higher OS and CSS rates compared with the non-attainment group (10-year OS 70.4% vs 58.1%, respectively [P = 0.016]; 10-year CSS 87.8% vs 70.0%, respectively [P = 0.036]). Multivariate analysis showed that the RARC pentafecta was a significant predictor of overall mortality (hazard ratio 0.561; P = 0.038). CONCLUSIONS: Patients who attained the RARC pentafecta had significantly better survival outcomes compared with those who did not. These criteria could be used to standardize assessment of the surgical quality of RARC. In the future, a similar study using an independent cohort is warranted to confirm our results.

Robot-assisted partial nephrectomy for high-complexity tumors (PADUA score ≥10): Perioperative, long-term functional and oncologic outcomes.

OBJECTIVES: To evaluate the safety and efficacy, and long-term functional and oncologic outcomes of robot-assisted partial nephrectomy in high-complexity tumors. METHODS: Data of 155 patients with a high-complexity tumor (PADUA score ≥10) were reviewed. Trifecta achievement, intra-, perioperative, functional, and oncologic outcomes were analyzed and compared between patients with increasing complexity. RESULTS: Of the 155 patients, 65 (41.9%) patients had a PADUA score of 10, 55 (35.5%) had a PADUA score of 11, and 35 (22.6%) had a PADUA score of 12-13, respectively. The median (interquartile range) operative time, warm ischemia time and estimated blood loss were 150 min (112-186 min), 26 min (23-32 min) and 250 mL (100-500 mL), respectively. Postoperatively, complications occurred in 25 (16.1%) patients, and positive surgical margins in 15 (10.5%) patients. Trifecta was achieved in 67 (43.2%) patients. At a median follow-up period of 58 months, the median estimated glomerular filtration rate preservation was 87% (78-110), and 12 (7.7%) patients developed new-onset chronic kidney disease. Recurrence-free survival and overall survival rates were 93.6% and 96.7%, respectively. Positive surgical margins were statistically different between the groups of PADUA score 10, 11 and 12-13 (P = 0.017), whereas functional and oncologic outcomes were similar. In multivariate logistic regression analysis, increasing tumor size (odds ratio 1.48, 95% confidence interval 1.21-1.87; P < 0.001) and the American Society of Anesthesiologists score 2/3 (odds ratio 0.48, 95% confidence interval 0.24-0.96; P = 0.041) were independent predictors of trifecta failure. CONCLUSIONS: Robot-assisted partial nephrectomy is a safe and effective treatment for high-complexity tumors providing excellent long-term functional and oncologic outcomes.

Long short-term memory artificial neural network model for prediction of prostate cancer survival outcomes according to initial treatment strategy: development of an online decision-making support system.

PURPOSE: The delivery of precision medicine is a primary objective for both clinical and translational investigators. Patients with newly diagnosed prostate cancer (PCa) face the challenge of deciding among multiple initial treatment modalities. The purpose of this study is to utilize artificial neural network (ANN) modeling to predict survival outcomes according to initial treatment modality and to develop an online decision-making support system. METHODS: Data were collected retrospectively from 7267 patients diagnosed with PCa between January 1988 and December 2017. The analyses included 19 pretreatment clinicopathological covariates. Multilayer perceptron (MLP), MLP for N-year survival prediction (MLP-N), and long short-term memory (LSTM) ANN models were used to analyze progression to castration-resistant PCa (CRPC)-free survival, cancer-specific survival (CSS), and overall survival (OS), according to initial treatment modality. The performances of the ANN and the Cox-proportional hazards regression models were compared using Harrell's C-index. RESULTS: The ANN models provided higher predictive power for 5- and 10-year progression to CRPC-free survival, CSS, and OS compared to the Cox-proportional hazards regression model. The LSTM model achieved the highest predictive power, followed by the MLP-N, and MLP models. We developed an online decision-making support system based on the LSTM model to provide individualized survival outcomes at 5 and 10 years, according to the initial treatment strategy. CONCLUSION: The LSTM ANN model may provide individualized survival outcomes of PCa according to initial treatment strategy. Our online decision-making support system can be utilized by patients and health-care providers to determine the optimal initial treatment modality and to guide survival predictions.

Lessons learned from clinical outcome and tumor features of patients underwent selective artery embolization due to postoperative bleeding following 2076 partial nephrectomies: propensity scoring matched study.

PURPOSE: To evaluate the clinical and tumor characteristics in patients undergoing selective artery embolization (SAE) for bleeding after partial nephrectomy (PN). METHODS: We retrospectively evaluated patients who underwent SAE from 2076 patients who underwent PN. The clinical and tumor characteristics of these patients were analyzed using entire data and propensity score matching (PSM). 76 patients who underwent PN (control, n = 38 patients; SAE, n = 38) were enrolled in PSM. RESULTS: SAE was performed in 41 patients who underwent open (19/1171), laparoscopic (4/60), and robot-assisted PN (18/845). The median period from PN to SAE was 12 days (interquartile range 8-24 day). The most common symptom of 31 (75.61%) patients was gross hematuria, followed by flank pain (3/41). Follow-up imaging revealed large pseudoaneurysm in 7 asymptomatic patients. The main reason for SAE on angiography was pseudoaneurysm (32/41), followed by arteriovenous fistula (5/41). Technical and clinical success was achieved in all patients. There was no statistical difference in the estimated glomerular filtration rate after 1 year, surgical methods, or baseline characteristics between the two groups. Conversely, there was statistically significant difference in ischemic time in the entire data and PSM. In the embolization group, renal masses showed statistically significant endophytic (p = 0.006) and posterior (p = 0.028) characteristics. CONCLUSIONS: SAE is an effective method for controlling postoperative bleeding while preserving renal function after PN. And, we suggest more attentive postoperative surveillance about vascular complications in patients with longer ischemia time or renal masses with endophytic and posterior locations.

Low-dose CT angiography using ASiR-V for potential living renal donors: a prospective analysis of image quality and diagnostic accuracy.

PURPOSE: To assess image quality and diagnostic accuracy of low-dose computed tomography (CT) angiography using adaptive statistical iterative reconstruction V (ASiR-V) for evaluating the anatomy of renal vasculature in potential living renal donors. MATERIALS AND METHODS: Eighty of 100 potential living renal donors were prospectively enrolled and underwent multiphase CT angiography (e.g., unenhanced, arterial, and venous phases) to evaluate the kidney for donation. Either low-dose using ASiR-V or standard protocol was randomly applied. Image quality was analyzed qualitatively and quantitatively with contrast-to-noise ratio (CNR) and signal-to-noise ratio (SNR). Renal artery and vein number, early branching vessel from renal arteries, and drainage of left-sided ascending lumbar vein to left renal vein were assessed. Reference standard for renal vasculature was surgical confirmation. RESULTS: Size-specific dose estimate of low-dose CT angiography (9.5 ± 0.8 mGy) was significantly lower than standard CT angiography (22.7 ± 4.1 mGy) (p < 0.001). Thus, radiation dose was reduced by 58.2% with low-dose CT. Both CNR and SNR of low-dose CT were significantly higher than those of standard CT (p < 0.001). Between the two CT methods, image quality was similar qualitatively (p > 0.05). Of 80 participants, 44 (55.0%) underwent nephrectomy. Both CT methods accurately predicted the anatomy of renal vasculature (standard CT, 100% for all variables; low-dose CT, 96.6% for renal vessel number or early branching vessel and 85.7% for drainage of left-sided ascending lumbar vein to left renal vein; p > 0.05 for all comparisons). CONCLUSION: Low-dose CT angiography using ASiR-V is useful to evaluate renal vasculature for potential living renal donors. KEY POINTS: • In this prospective study, adaptive statistical iterative reconstruction V (ASiR-V) allowed 58.2% dose reduction while maintaining diagnostic image quality for renal vessels. • As compared with the standard protocol, the dose with ASiR-V was significantly lower (9.5 ± 0.8 mGy) than with standard computed tomography (CT) angiography (22.7 ± 4.1 mGy). • Low-dose CT using ASiR-V is useful for living donor evaluation before nephrectomy.

Prospective assessment of urinary neutrophil gelatinase-associated lipoprotein in living kidney donors: toward understanding differences between chronic kidney diseases of surgical and medical origin.

OBJECTIVES: To evaluate the clinical implications of postoperative urinary neutrophil gelatinase-associated lipoprotein (NGAL) changes and the association between urinary NGAL (uNGAL) and renal function in living kidney donors. SUBJECTS, PATIENTS AND METHODS: We included 76 healthy adults who underwent donor nephrectomy between December 2013 and November 2014. Perioperative serum creatinine (sCr), uNGAL, serum NGAL (sNGAL), and urinary microalbumin were prospectively measured until 6 months postoperatively. Patients with chronic kidney disease (CKD) due to medical disorders who visited our outpatient clinic during the same period were included for comparison. RESULTS: The mean (SD) preoperative uNGAL of donors was 5 (5.17) ng/mL. uNGAL (corrected for urinary creatinine) was maximal at 1-2 days postoperatively, decreased on postoperative day 3, and stabilised by 7 days after surgery. Postoperative uNGAL was not associated with sex, age, or preoperative renal function. When corrected for sNGAL to compensate for the systemic increase in NGAL with major surgery, uNGAL on days 1-3 postoperatively was negatively correlated with sCr. Postoperatively, donor uNGAL remained higher than preoperatively for up to 6 months but was significantly lower than in patients with medical CKD with similar glomerular filtration rates. CONCLUSION: Acute kidney injury due to hyperfiltration of remnant kidney after donor nephrectomy was maximal within 1-2 days postoperatively. The rise in uNGAL during this period in donors was negatively correlated with postoperative sCr levels. Decreased renal function after nephrectomy differs from that of medical CKD.

Functional and oncological outcomes of open, laparoscopic and robot-assisted partial nephrectomy: a multicentre comparative matched-pair analyses with a median of 5 years' follow-up.

OBJECTIVES: To compare outcomes at a 5-year median follow-up among different partial nephrectomy (PN) approaches: robot-assisted (RAPN), laparoscopic (LPN) and open partial nephrectomy (OPN). PATIENTS AND METHODS: We retrospectively analysed 1 308 patients who underwent PN (RAPN, n = 380; LPN, n = 206; OPN, n = 722) between 2006 and 2012 at one of four academic centres. We performed 1:1:1 propensity-score-matching adjustment based on confounding variables among groups, and 366 patients (122 in each group) were included in the final analysis. Survival rates were analysed using the Kaplan-Meier method. RESULTS: The median follow-up periods were 60, 59.8 and 64.1 months for RAPN, LPN and OPN, respectively. In the matched groups, RAPN resulted in significantly lower mean estimated blood loss compared with LPN (P = 0.025) and OPN (P = 0.040), while LPN was associated with a longer mean operating time compared with RAPN (P = 0.001) and OPN (P = 0.001). The hospital stay was shorter in the RAPN group (P = 0.008). Regarding the oncological outcomes, there were no significant differences among the three groups in local recurrence rate (P = 0.882), distant metastasis rate (P = 0.816) or deaths from cancer (P = 0.779). At latest follow-up, the incidence of chronic kidney disease (CKD) upstaging was significantly lower in RAPN compared with LPN (20.55% vs 32%; P = 0.035) and OPN (20.5% vs 33.6%; P = 0.038). The 5-year CKD free-survival rate was significantly higher (78.4%) in the RAPN group compared with 58.8% and 65.8% in the LPN and OPN groups, respectively (log-rank P = 0.031). CONCLUSIONS: In the present study, RAPN, LPN and OPN had similar local recurrence, distant metastasis and cancer-related death rates at a 5-year median follow-up. In terms of functional outcomes, RAPN was associated with a lower incidence of CKD upstaging compared with OPN and LPN.

Solid Small Renal Mass Without Gross Fat: CT Criteria for Achieving Excellent Positive Predictive Value for Renal Cell Carcinoma.

OBJECTIVE: The purpose of this study was to evaluate CT criteria for achieving high positive predictive value (PPV) for renal cell carcinoma (RCC) in patients with solid small renal masses (SRMs) less than 4 cm without macroscopic fat. MATERIALS AND METHODS: One hundred fifty consecutive patients with a solid SRM without macroscopic fat (mean size ± SD, 2.5 ± 0.8 cm) who underwent CT including unenhanced, corticomedullary (CMP), and nephrographic phases (NP) were evaluated. Pathologically proven solid SRMs without macroscopic fat were classified into RCC (n = 131) and not RCC (n = 19). A "persistent low" sign was defined as a focal area or areas of low attenuation seen at the same location within the lesion on both CMP and NP imaging. Calcification, shape, and lesion attenuation on unenhanced CT were analyzed by two independent readers. RESULTS: PPV of CT criteria (calcification [criterion 1] or spherical shape, lower or equal attenuation, and persistent low sign [criterion 2]) for RCC was 98.3% (58/59) for reader 1 and 100% (53/53) for reader 2. Weighted kappa of interreader agreement was 1.000 for calcification, 0.966 of lower or equal attenuation, 0.834 for spherical shape, 0.823 for persistent low sign, and 0.829 for CT criteria. CONCLUSION: Interpretation of CT allowed reproducible and excellent PPV for RCC. Current CT criteria may effectively shorten the management process for solid SRMs without macroscopic fat by reducing unnecessary biopsy for a substantial number of RCCs showing typical CT findings.

Predictors of biochemical recurrence after Retzius-sparing robot-assisted radical prostatectomy: Analysis of 359 cases with a median follow-up period of 26 months.

OBJECTIVES: Our aim was to evaluate the predictors of biochemical recurrence after Retzius-sparing robot-assisted radical prostatectomy. METHODS: The study cohort consisted of 359 consecutive non-metastatic prostate cancer patients who underwent Retzius-sparing robot-assisted radical prostatectomy between November 2012 and January 2016. According to the National Comprehensive Cancer Network prostate cancer risk classification, 164 patients (45.7%) had high- or very high-risk prostate cancer. No patient received adjuvant therapy until documented biochemical recurrence. Biochemical recurrence-free survival was estimated using the Kaplan-Meier method. Univariable and multivariable Cox proportional hazards regression models were used to determine variables predictive of biochemical recurrence. RESULTS: The median follow-up period was 26 months (interquartile range 19-38 months). The overall biochemical recurrence rate was 14.8%, and the median time to biochemical recurrence was 11 months (interquartile range 6-22 months). The 3-year biochemical recurrence-free survival probability was 71.2%, 72.1%, 88.7%, 82.3% and 95.7% in very high-, high-, intermediate-, low- and very low-risk prostate cancer, respectively (log-rank, P < 0.001). On multivariable analysis, preoperative prostate-specific antigen (hazard ratio 1.03, 95% confidence interval 1.02-1.04; P < 0.0001), percentage of maximum core involvement on biopsy (hazard ratio 1.02, 95% confidence interval 1.01-1.03; P = 0.029) and clinical stage ≥T3a (hazard ratio 2.12, 95% confidence interval 1.02-4.39; P = 0.043) were predictors of biochemical recurrence, whereas pathological Gleason score ≥8 (hazard ratio 5.63, 95% confidence interval 1.62-19.61; P = 0.007) and pathological tumor volume (hazard ratio 1.08, 95% confidence interval 1.04-1.20; P < 0.001) were the main pathological predictors of biochemical recurrence. CONCLUSIONS: Retzius-sparing robot-assisted radical prostatectomy confers effective biochemical recurrence control at the mid-term follow-up period. Preoperative prostate-specific antigen, advanced clinical stage and higher Gleason score were important predictors of biochemical recurrence after Retzius-sparing robot-assisted radical prostatectomy. Long-term oncological safety still needs to be established.

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.

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.

Mitochondrial Sirt3 supports cell proliferation by regulating glutamine-dependent oxidation in renal cell carcinoma.

Clear cell renal carcinoma (RCC), the most common malignancy arising in the adult kidney, exhibits increased aerobic glycolysis and low mitochondrial respiration due to von Hippel-Lindau gene defects and constitutive hypoxia-inducible factor-α expression. Sirt3 is a major mitochondrial deacetylase that mediates various types of energy metabolism. However, the role of Sirt3 as a tumor suppressor or oncogene in cancer depends on cell types. We show increased Sirt3 expression in the mitochondrial fraction of human RCC tissues. Sirt3 depletion by lentiviral short-hairpin RNA, as well as the stable expression of the inactive mutant of Sirt3, inhibited cell proliferation and tumor growth in xenograft nude mice, respectively. Furthermore, mitochondrial pyruvate, which was used for oxidation in RCC, might be derived from glutamine, but not from glucose and cytosolic pyruvate, due to depletion of mitochondrial pyruvate carrier and the relatively high expression of malic enzyme 2. Depletion of Sirt3 suppressed glutamate dehydrogenase activity, leading to impaired mitochondrial oxygen consumption. Our findings suggest that Sirt3 plays a tumor-progressive role in human RCC by regulating glutamine-derived mitochondrial respiration, particularly in cells where mitochondrial usage of cytosolic pyruvate is severely compromised.

A novel mathematical model to predict the severity of postoperative functional reduction before partial nephrectomy: the importance of calculating resected and ischemic volume.

PURPOSE: Preoperatively predicting postoperative kidney function is an essential step to achieve improved renal function and prevent chronic kidney disease. We introduce a novel formula especially to calculate resected and ischemic volume before partial nephrectomy. We examined whether resected and ischemic volume would have value for predicting postoperative renal function. MATERIALS AND METHODS: We performed a retrospective cohort study in 210 patients who underwent robotic partial nephrectomy between September 2006 and October 2013 at a tertiary cancer care center. Based on abdominopelvic computerized tomography and magnetic resonance imaging we calculated resected and ischemic volume by the novel mathematical formula using integral calculus. We comparatively analyzed resected and ischemic volume, and current nephrometry systems to determine the degree of association and predictability regarding the severity of the postoperative functional reduction. RESULTS: On multivariable analysis resected and ischemic volume showed a superior association with the absolute change in estimated glomerular filtration rate/percent change in estimated glomerular filtration rate (B = 6.5, p = 0.005/B = 6.35, p = 0.009). The ROC AUC revealed accurate predictability of resected and ischemic volume on the stratified event of an absolute change in estimated glomerular filtration rate/event of percent change in estimated glomerular filtration rate compared to 3 representative nephrometry systems. The calibration plot of this model was excellent (close to the 45-degree line) within the whole range of predicted probabilities. CONCLUSIONS: We report a method of preoperatively calculating resected and ischemic volume with a novel formula. This method has superior correlation with the absolute and percent change in estimated glomerular filtration rate compared to current nephrometry systems. The predictive model achieved a strong correlation for the absolute and percent change in estimated glomerular filtration rate.

Renal function is the same 6 months after robot-assisted partial nephrectomy regardless of clamp technique: analysis of outcomes for off-clamp, selective arterial clamp and main artery clamp techniques, with a minimum follow-up of 1 year.

OBJECTIVE: To compare the renal functional outcomes, with >1 year of follow-up, of patients who underwent robot-assisted partial nephrectomy (RAPN) performed with different clamping techniques. PATIENTS AND METHODS: The peri-operative data of patients undergoing RAPN performed with different clamping techniques were retrospectively analysed (group 1: off-clamp, n = 23; group 2: selective clamp, n = 25; group 3: main artery clamp, n = 114). The main outcome measures were postoperative serum creatinine level, estimated glomerular filtration rate (eGFR) and percentage change in eGFR, the data for which were collected at periodic intervals during the first 12 months and annually thereafter, in addition to late eGFR value. Only patients with >1 year of follow-up were included in the analysis. RESULTS: The baseline characteristics of groups 2 and 3 were similar, while patients in group 1 had smaller sized tumours and lower tumour complexity. The median follow-up periods were 45 (group 1), 20 (group 2) and 47 (group 3) months. The median clamping times were 24.8 min in the main artery clamp and 18 min in the selective artery clamp groups. Group 2 had greater median blood loss volume (100 vs 500 vs 200 mL for groups 1, 2 and 3, respectively; P < 0.01) and a longer length of hospital stay (3 vs 4 vs 3 days for groups 1, 2 and 3, respectively; P = 0.02). No significant differences were found among the groups with regard to transfusion rates, positive surgical margin rates, complications, recurrence or mortality rates. Groups 1 and 2 had significantly less deterioration of postoperative renal function during the first 3 months after surgery (P = 0.04; percent change in eGFR -1.5, -2 and -8% for groups 1, 2 and 3, respectively), but this beneficial outcome was not observed after 6 months or for the latest eGFR measurement (P = 0.48; latest percent change in eGFR -3, -6 and -3.5% for groups 1, 2 and 3, respectively). In regression analysis, baseline eGFR, type of clamp procedure and tumour complexity score were predictive of normal renal function 7 days after surgery, while only baseline eGFR and age could predict it 1 year postoperatively. CONCLUSIONS: Off-clamp and selective artery clamp techniques result in superior short-term renal functional outcomes compared with the main artery clamp approach; however, after the 6th postoperative month, there were no significant differences regarding the functional outcome among the above surgical techniques, as long as the warm ischaemia time was 20-30 min.

Clinical values of selective-clamp technique in robotic partial nephrectomy.

PURPOSE: In the era of robotic partial nephrectomy (RPN), several efforts on improved renal functional outcome have been reported. Selective-clamp is a novel technique that eliminates global ischemia, the clinical value of which needs to be demonstrated. The purpose of this study was to compare the postoperative functional outcomes of patients who underwent selective-clamp and total-clamping RPN. PATIENTS AND METHODS: From February 2009 to October 2012, a database of 126 consecutive patients who underwent RPN was retrospectively analyzed, 117 patients met our inclusion criteria and were stratified into two groups, 20 patients underwent selective-clamp RPN, and 97 patients underwent total-clamping RPN. Post hoc power analysis was subsequently performed for calculation of sufficient sample size. Demographics/tumor characteristics, functional outcomes and complications were analyzed. RESULTS: All selective-clamp RPN cases were successfully performed. Mean tumor size was 3.4 cm [standard deviation (SD): ±1.4], mean RENAL nephrometry score was 7.3 (SD: ±2.0), and no Clavien-Dindo III-V complications were recorded. Selective-clamp RPN group had a significantly lower percentage decrease in the postoperative estimated glomerular filtration rate at 1 week (1.8 vs. 20.8 ml/min/1.73 m(2), p = 0.001) and 3 months (0 vs. 9.9 ml/min/1.73 m(2), p = 0.032) when compared with the total-clamping RPN group. There were no significant differences in surgical margin and complication rates. CONCLUSIONS: Selective-clamp confers improved renal functional outcomes in comparison to total-clamping RPN, with acceptable complications and oncological outcomes even in large and complex tumors.

Usefulness of the diameter-axial-polar nephrometry score for predicting perioperative parameters in robotic partial nephrectomy.

PURPOSE: The present study aimed to verify the association between diameter-axial-polar (DAP) nephrometry and surgical outcomes, postoperative renal function, and perioperative complications in patients undergoing robotic partial nephrectomy (RPN). METHODS: Diameter-axial-polar nephrometry was assessed using computed tomography or magnetic resonance imaging on 158 patients who received RPN between July 2007 and February 2013. Demographic data, surgical data, and perioperative complications were recorded, and percent change between the preoperative and last estimated glomerular filtration rate (eGFR) was determined. Linear regression analysis was conducted to assess the relationship between the DAP sum score and warm ischemia time (WIT), estimated blood loss (EBL), and percent decrease in eGFR. Multivariable linear regression analysis was conducted to determine the relationship between each DAP scoring parameter and surgical outcomes. RESULTS: The median patient age was 50.5 years and median DAP sum score was 6. On linear regression, the DAP sum score was associated with WIT and EBL. On multivariable regression, all DAP parameters were associated with WIT, but the polar distance was not associated with EBL. Patients with a higher DAP sum score showed greater decrease in eGFR after RPN. Patients with a DAP sum score of 6 or higher had a higher risk of major complications than those with a DAP sum score below 6. CONCLUSIONS: Diameter-axial-polar nephrometry predicted WIT and EBL in patients who underwent RPN. It was also associated with the decrease in eGFR and rate of major perioperative complications, and thus can be useful for surgical planning or patient counseling before RPN.

Prospective measurement of urinary microalbumin in living kidney donor nephrectomy: toward understanding the renal functional recovery period.

PURPOSE: We determined the clinical implications of perioperative urinary microalbumin excretion in relation to renal function after living donor nephrectomy. MATERIALS AND METHODS: Between August 2010 and January 2013, 259 donors undergoing live donor nephrectomy were enrolled in the study. The donor urinary albumin-to-creatinine ratio was measured perioperatively, and changes in perioperative urinary albumin-to-creatinine ratio and the implications of preoperative microalbuminuria (urinary albumin-to-creatinine ratio 30 mg/gm or greater) were investigated. The relationships between perioperative urinary albumin-to-creatinine ratio and recovery of renal function and implantation biopsy histology were also analyzed. RESULTS: Mean ± SD preoperative urinary albumin-to-creatinine ratio was 7.1±12.7 mg/gm. The urinary albumin-to-creatinine ratio was increased after 1 day (24.7±18.9 mg/gm, p <0.001) and stabilized after 1 month (10.3±10.7 mg/gm, p <0.001). Preoperative microalbuminuria was not associated with perioperative estimated glomerular filtration rate during a followup period of 6 months but was associated with histological abnormalities. Donors with a higher urinary albumin-to-creatinine ratio before donation, even in the normal range, consistently had an increased postoperative urinary albumin-to-creatinine ratio. A ROC curve analysis showed that age, preoperative estimated glomerular filtration rate and 1-month postoperative urinary albumin-to-creatinine ratio were highly predictive of delayed recovery of renal function (AUC 0.884, p <0.001). The 1-month postoperative urinary albumin-to-creatinine ratio was associated with delayed recovery of renal function (OR 1.05 for each 0.1 mg/gm increase, p=0.021). CONCLUSIONS: Donors with higher preoperative urinary albumin-to-creatinine ratio levels require close observation because there is a greater possibility of microalbuminuria developing after donation even if the ratio is within the normal range. A higher urinary albumin-to-creatinine ratio was also associated with delayed recovery of renal function and histological abnormalities.

Retzius-sparing robot-assisted laparoscopic radical prostatectomy: combining the best of retropubic and perineal approaches.

OBJECTIVE: To compare the early peri-operative, oncological and continence outcomes of Retzius-sparing robot-assisted laparoscopic radical prostatectomy (RALP) with those of conventional RALP. MATERIALS AND METHODS: Data from 50 patients who underwent Retzius-sparing RALP and who had at least 6 months of follow-up were prospectively collected and compared with a database of patients who underwent conventional RALP. Propensity-score matching was performed using seven preoperative variables, and postoperative variables were compared between the groups. RESULTS: A total of 581 patients who had undergone RALP were evaluated in the present study. Although preoperative characteristics were different before propensity-score matching, these differences were resolved after matching. There were no significant differences in mean length of hospital stay, estimated blood loss, intra- and postoperative complication rates, pathological stage of disease, Gleason scores, tumour volumes and positive surgical margins between the conventional RALP and Retzius-sparing RALP groups. Console time was shorter for Retzius-sparing RALP. Recovery of early continence (defined as 0 pads used) at 4 weeks after RALP was significantly better in the Retzius-sparing RALP group than in the conventional RALP group. CONCLUSIONS: The present results suggest that Retzius-sparing RALP, although technically more demanding, was as feasible and effective as conventional RALP, and also led to a shorter operating time and faster recovery of early continence. Retzius-sparing RALP was also reproducible and achievable in all cases.

Yonsei nomogram to predict lymph node invasion in Asian men with prostate cancer during robotic era.

OBJECTIVE: To develop a novel nomogram to predict lymph node invasion (LNI) in Asian men undergoing radical prostatectomy (RP) and pelvic LN dissection (PLND) for localised prostate cancer. PATIENTS AND METHODS: The patient cohort included 541 patients who underwent robot-assisted RP and PLND by a single surgeon between January 2008 and December 2011. Patients with dissection of <10 LNs, prostate-specific antigen (PSA) levels of >50 ng/mL, incomplete biopsy data, and treatment with neoadjuvant therapy were excluded. RESULTS: The median (interquartile range) number of LNs removed was 17 (14-22) and 45 patients (8.3%) had LN metastases. On multivariate logistic regression analysis, PSA level, clinical stage and Gleason score were independent predictors of LNI. The bootstrap corrected area under curve of the model incorporating PSA level, clinical stage, and biopsy Gleason score was 0.883. With a cutoff value of 4%, PLND could be omitted in 326 patients (60.2%), missing only two patients (4.4%) with LNI. The sensitivity, specificity, positive predictive value and negative predictive value were 95.6%, 65.3%, 20.0% and 99.4%, respectively. CONCLUSIONS: We report a nomogram to predict LNI in Asian men with prostate cancer. The model demonstrated high accuracy and could be used for counselling patients and the selection of candidates for PLND.