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.

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.

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.

Laparoendoscopic single-site (LESS) robot-assisted nephroureterectomy: comparison with conventional multiport technique in the management of upper urinary tract urothelial carcinoma.

OBJECTIVE: To compare the peri-operative, pathological and oncological outcomes of laparoendoscopic single-site (LESS) robot-assisted nephroureterectomy (LESS-RALNU) with those of multiport robot-asssisted nephroureterectomy (M-RALNU). PATIENTS AND METHODS: A total of 38 patients with upper urinary tract urothelial carcinoma underwent LESS-RALNU (n = 17) or M-RALNU (n = 21) by a single surgeon at a tertiary institution. Data were obtained from a prospectively maintained database. RESULTS: Patients' demographics and tumour characteristics were similar between the M-RALNU and LESS-RALNU groups. The mean follow-up was 48.4 months for M-RALNU and 30.9 months for LESS-RALNU (P = 0). The mean operating time, estimated blood loss and length of hospitalization for M-RALNU and LESS-RALNU were 251 min, 192 mL, 6.5 days and 247 min, 376 mL and 5.4 days, respectively (P > 0.05). Overall, there were no significant differences in complication rates, although three patients in the LESS-RALNU group required blood transfusion, whereas no patient in the M-RALNU group did (P = 0.081). The proportion of patients with bladder recurrence, local recurrence and distant metastases was similar between the two groups. There were no significant differences in the recurrence-free survival, cancer-specific survival and overall survival rates between the two groups. CONCLUSIONS: Although the oncological and peri-operative outcomes of patients who underwent LESS-RALNU compared well with those who underwent M-RALNU and with series of other surgical approaches, LESS-RALNU might result in greater intra-operative blood loss. We suggest careful selection of patient for this technique.

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.

Laparoendoscopic single-site (LESS) robot-assisted partial nephrectomy (RAPN) reduces postoperative wound pain without a rise in complication rates.

OBJECTIVE: To compare long-term functional outcomes and pain scale scores of patients who underwent laparoendoscopic single-site (LESS)- robot-assisted partial nephrectomy (RAPN) to those who underwent conventional RAPN (C-RAPN), as LESS surgery is increasingly being adopted by urologists worldwide to reduce morbidities and scarring associated with surgical interventions. PATIENTS AND METHODS: In all, 167 consecutive patients who had RAPN were identified from our Institutional Review Board-approved computerised database between October 2006 to July 2012. Patients were stratified into two groups: 80 patients who underwent C-RAPN and 79 who underwent LESS-RAPN. RESULTS: The LESS-RAPN group had a longer warm ischaemia time [WIT, mean (sd) 26.5 (10.5) vs 19.8 (13.1) min; P = 0.001] and total operation time [TOT, mean (sd) 210.3 (83.4) vs 183.1 (76.1) min; P = 0.033] when compared with the C-RAPN group. While, the LESS-RAPN group and C-RAPN group were not significantly different for the number of patients with negative surgical margins [77 (96.2%) vs 73 (91.4%); P = 0.194), absolute change in postoperative renal function [mean (sd) -6.5 (16.7)% vs -7.6 (16.7)%; P = 0.738) and postoperative complications rate [12 (15.0%) vs 10 (12.6%); P = 0.279). Furthermore, the LESS-RAPN group had lower visual analogue pain scale (VAPS) scores at discharge [mean (sd) 2.1 (1.3) vs 1.7 (1.0); P = 0.048]. CONCLUSIONS: Despite a significantly longer WIT and TOT, the functional outcomes of LESS-RAPN were comparable to those of C-RAPN for tumours of similar mean sizes and complexities, without any detriments in oncological and complications outcomes. On discharge, patients who underwent LESS-RAPN also reported lower pain levels as one of the advantages of minimally invasive surgery. With the development of instrumentation specifically designed for single-site surgery, LESS could be more easily conducted in patients who are interested in improved quality of life outcomes.

Assessing the anatomical characteristics of renal masses has a limited effect on the prediction of pathological outcomes in solid, enhancing, small renal masses: results using the PADUA classification system.

OBJECTIVE: To evaluate whether assessing the anatomical characteristics of renal masses increases the accuracy of prediction of tumour pathology in small renal masses (SRMs). PATIENTS AND METHODS: We retrospectively reviewed 1129 consecutive patients who underwent extirpative surgeries for a clinical T1 renal mass, for which the preoperative aspects and dimensions used for an anatomical (PADUA) classification were available. Multivariate logistic regression analyses of demographic and anatomical characteristics were performed. Nomograms to predict malignancy and high grade pathology were constructed using a basic model (age, sex and tumour size), and an extended model (anatomical characteristics incorporated into the basic model), and the area under the curve (AUC) between models was compared. RESULTS: Age, sex and tumour size were significantly associated with malignancy and high grade pathology in the T1 and T1a category (except sex for high grade pathology in T1a tumours). Exophytic rate (T1 and T1a) and renal sinus or urinary collecting system involvement (only T1a) were also significant predictors of high grade pathology. Nomograms using the extended model for malignancy showed an insignificant AUC increase compared with those using the basic model (T1, from 0.771 to 0.780, P = 0.149, and T1a, from 0.803 to 0.819, P = 0.055). For high grade pathology, the extended model achieved a significant AUC increase (from 0.595 to 0.643, P = 0.014) in the T1a category, but the AUC for both T1 and T1a tumours showed merely modest competence (0.654 and 0.643, respectively). CONCLUSION: Age, sex and tumour size are the primary predictors of tumour pathology of SRMs, and incorporating other anatomical characteristics has only a limited positive effect on the accuracy of prediction of pathological outcomes.

Tumor volume adds prognostic value in patients with organ-confined prostate cancer.

PURPOSE: This study was designed to assess the independent prognostic value of tumor volume (TV) and whether adding TV provides additional prognostic information for predicting biochemical recurrence (BCR) after radical prostatectomy. METHODS: We reviewed the medical records of 1,129 patients who underwent radical prostatectomy between July 2005 and July 2011. TV was categorized as minimal (≤1.0 ml), moderate (1.1-5.0 ml), or extensive (>5.0 ml). Cox regression analysis was performed to identify independent predictors of BCR. The predictive accuracies of Cox's proportional hazard regression models with and without TV were quantified and compared using time-dependent receiver operating characteristic curve analysis. RESULTS: Increasing TV was associated with higher prostate specific antigen, pathological Gleason score, and pathologic tumor stage. TV was an independent predictor of BCR in multivariate analysis (p<0.001). When patients were stratified by organ-confined and nonorgan-confined tumor groups, TV remained an independent predictor of BCR in organ-confined tumors (p<0.001). In the nonorgan-confined tumor group, a significant difference was found only between extensive versus minimal TV (p=0.023). The predictive accuracy of the Cox regression model increased significantly by adding TV in organ-confined tumor group (0.748 vs. 0.704, p<0.05) but not in nonorgan-confined group (0.742 vs. 0.734, p>0.05). CONCLUSIONS: TV was an independent prognostic predictor of BCR in organ-confined prostate cancers and provided additional prognostic information with increased predictive accuracy. In contrast, TV did not increase the predictive accuracy in nonorgan-confined tumor. TV should be considered as a prognosticator in organ-confined tumors.

Gleason 5+4 has worse oncological and pathological outcomes compared with Gleason 4+5: significance of Gleason 5 pattern.

BACKGROUND: The purpose of this study was to evaluate the pathological and oncological significance of Gleason (G) 5 pattern in high-grade PCa after robotic-assisted radical prostatectomy (RARP). MATERIALS AND METHODS: From a cohort of 1,046 men, 159 post-RARP patients by a single surgeon with pathological G8 (N=79) and G9 (N=80) met our inclusion criteria. G9 cancers were sub-stratified into G4+5 (N=58) and G5+4 (N=22). Clinical and pathological outcomes were evaluated with the t test or Mann-Whitney U test for continuous variables and the Pearson χ2 test for categorical variables. The Kaplan-Meier method was used to estimate the biochemical recurrence-free survival (BCRFS), and survival curves were compared using the log-rank test. Multivariate analysis was performed with Cox regression analysis. RESULTS: Baseline characteristics across all subgroups were similar except for number of positive cores on biopsy. There was a trend toward worse pathological and oncological outcomes in G9 cancers when compared with G8, although only tumor volume (TV), extracapsular extension (ECE) of tumor and lymph nodes involvement (LNI) achieved statistical significance. G4+5 PCa were statistically more likely to have ECE and a higher TV than G4+4 although the BCRFS were not significantly different. G5+4 cancers were associated with a significantly higher proportion of patients with LNI and had a statistically significant poorer BCRFS compared with G4+5 patients. CONCLUSIONS: Oncological and pathological outcomes of G8 were significantly better than G9 and merited distinction between them. G5+4 harbors a much poorer BCRFS compared with G4+5, and hence we suggest considerations for immediate adjuvant treatments.

Upgrading of Gleason score and prostate volume: a clinicopathological analysis.

OBJECTIVE: To more clearly elucidate the association between prostate volume and Gleason score (GS) upgrading. PATIENT AND METHODS: We reviewed 451 patients with prostate cancer with a GS of 6 on biopsy, who underwent radical prostatectomy without neoadjuvant treatment. As a preoperative variable, we assessed the independent effect of prostate volume on GS upgrading. To evaluate the association between prostate volume and GS upgrading, we developed multivariate models with volumetric pathological variables, including postoperative tumour volume and percent tumour volume (tumour volume as a percentage of prostate volume). RESULTS: GS upgrading was observed in 194 patients (43.0%). As a preoperative variable, smaller prostate volume was an independent predictor of GS upgrading. In regression analysis, prostate volume and postoperative tumour volume were inversely correlated. On multivariate analysis including volumetric pathological variables, tumour volume was a strong independent factor influencing GS upgrading, and prostate volume lost statistical significance after adjusting for tumour volume. Percent tumour volume was inversely correlated with GS upgrading after adjusting for tumour volume. CONCLUSIONS: Smaller prostate volume was an independent predictor of GS upgrading as a preoperative variable. The inverse relationship between prostate volume and GS upgrading seems to be attributable to cancer biology, which was represented by tumour volume in our study. Percent tumour volume was also inversely associated with GS upgrading. These results suggest that biological factors and sampling error both play important roles in GS upgrading.

Extended vs standard lymph node dissection in robot-assisted radical prostatectomy for intermediate- or high-risk prostate cancer: a propensity-score-matching analysis.

UNLABELLED: WHAT'S KNOWN ON THE SUBJECT? AND WHAT DOES THE STUDY ADD?: Although lymph node dissection (LND) is known as the most accurate method of nodal staging, the therapeutic role of LND remains undetermined. This is mainly because of the lack of randomized prospective studies and the fact that retrospective analyses often result in bias and misinterpretation. To overcome the limitation of retrospective analysis, we matched preoperative variables using propensity scores and compared the outcomes between patients treated with robot-assisted eLND and sLND. In the matched cohort, robot-asssited eLND achieved an increased detection rate of lymph node metastases; however, the therapeutic benefit was not statistically significant between the two groups on short-term follow-up. OBJECTIVE: To compare the pathological and biochemical outcomes between extended lymph node dissection (eLND) and standard lymph node dissection (sLND) in patients undergoing robot-assisted radical prostatectomy for intermediate- or high-risk prostate cancer. PATIENTS AND METHODS: A total of 905 patients underwent robot-assisted radical prostatectomy and lymph node dissection (LND) by a single surgeon between June 2006 and January 2011. Of these, 170 patients who underwent robot-assisted eLND and 294 patients who underwent robot-assisted sLND for intermediate- or high-risk prostate cancer were included in the study. Propensity-score matching was performed using the preoperative variables which included age, body mass index, prostate-specific antigen, clinical stage, biopsy Gleason score 1 and 2, total number of biopsied cores, number of positive cores and prostate volumes. Pathological and biochemical outcomes were assessed according to the extent of LND. RESULTS: The median (range) follow-up period was 36 (12-77) months and the median number of lymph nodes removed was 21 and 12 in the eLND and sLND groups, respectively. Propensity-score matching resulted in 141 patients in each group. Although patients who underwent eLND had a higher clinical stage, biopsy Gleason score and number of positive cores than those treated with sLND in the entire cohort, there were no preoperative between-group differences in the matched cohort. In the matched cohort, lymph node metastases were detected at a significantly higher rate in the eLND than in the sLND group (12.1 vs. 5.0%, P = 0.033). In the matched cohort, the 3-year biochemical recurrence-free survival rates were 77.8 and 73.5% in the eLND and sLND groups, respectively, which was not significant (hazard ratio 0.85, P = 0.497). CONCLUSION: Robot-assisted eLND achieved an increased lymph node yield and higher detection rate of lymph node metastases; however, robotic eLND did not alter biochemical outcomes in a short-term follow-up.

Current status of robot assisted laparoscopic radical nephroureterectomy for management of upper tract urothelial carcinoma.

Upper tract urothelial carcinomas (UUT-UC) are usually aggressive tumours and require radical treatments. The standard of care for localised UUT-UC is radical nephroureterectomy (RNU). Robot-assisted laparoscopic surgeries are currently employed in various urological procedures, including RNU. We conducted a literature search on medical databases (PubMed/ MEDLINE) using free text keywords nephroureterectomy, distal ureter, bladder cuff, urothelial carcinoma and/or robotic. In this review, we aim to provide an up-to-date status on robot-assisted laparoscopic nephroureterectomy (RAL-NU) for the management of UUT-UC. The various surgical techniques and approaches for RAL-NU and retroperitoneal lymph node dissection (RPLND) will be discussed and their perioperative and early oncological outcomes reported. The feasibility and safety of RAL-NU has been demonstrated in a number of studies but intermediate and long term clinical and oncological outcomes are still lacking.

Current status of robot-assisted laparoscopic radical prostatectomy: how does it compare with other surgical approaches?

The aim was to review the current status and evaluate the outcomes of robot-assisted laparoscopic radical prostatectomy in comparison with open radical prostatectomy and laparoscopic radical prostatectomy. Between January 2008 and June 2012, published English language comparative studies comparing robot-assisted laparoscopic radical prostatectomy with either open radical prostatectomy and/or laparoscopic radical prostatectomy were reviewed. End-points for this review include oncological, functional and perioperative outcomes, and complications. Compared with laparoscopic radical prostatectomy and/or open radical prostatectomy, robot-assisted laparoscopic radical prostatectomy offered at least equivalent oncological control. Current evidence seems to suggest a superiority of robot-assisted laparoscopic radical prostatectomy over open radical prostatectomy and laparoscopic radical prostatectomy in terms of functional outcomes, such as urinary continence and potency. Risks of perioperative complications were also low after robot-assisted laparoscopic radical prostatectomy. Robot-assisted laparoscopic radical prostatectomy offers at least equivalent oncological and functional outcomes with low risks of complications when compared with open radical prostatectomy and laparoscopic radical prostatectomy. However, there is a paucity of high-level evidence available in current literature.

Technical insights to multivisceral resections using the da Vinci Xi.

BACKGROUND: There have been few reports on the feasibility and safety of robotic multivisceral surgeries. The da Vinci Xi boasts significant upgrades that improve its applicability in combined resections. We report our early experience of multivisceral, multi-quadrant resections with the Xi system. METHODS: Between May 2015 and August 2019, 13 multivisceral resections were performed. Patient demographics, procedural data, and perioperative outcomes were evaluated. RESULTS: The procedures were completed at a median operative time of 290 (range, 210-535) minutes. The median postoperative length of hospital stay was 3.5 (range, 2-7) days. There was one case of readmission for anastomotic leak, but no positioning injuries, external robot arm collisions or issues arising from trocar position. There were no cases of perioperative mortality. CONCLUSION: Multivisceral resections can be safely accomplished using the Xi. Further studies are necessary to ascertain whether there are benefits of the robotic approach over conventional laparoscopy in these complex cases.

Is there still a role of balloon dilatation of benign ureteric strictures in 2019?

Introduction and Objectives: Reconstructive surgery for benign ureteric strictures and long term nephrostomy are often invasive and lead to poor quality of life. Balloon dilatation has the potential to bridge this gap. We present the outcome of our series and examine the risk factors of stricture recurrence.Materials and Methods: There were 109 strictures in our series from August 2012 to July 2018 in our single center retrospective cohort analysis. All strictures were dilated retrogradely or antegradely and followed by stenting. Follow-up imaging was done to assess stricture recurrence.Results: Mean patient age was 57.7-years-old (SD ± 12.6). Mean follow-up was 20.2 months (SE ± 1.8). All strictures were successfully dilated and stented. Overall, mean patency rate was 63.7% at mean follow-up of 20.2 months (SE ± 1.8). Strictures caused by stone/inflammation had 28.0% (21/75) risk of recurrence compared to iatrogenic causes, 63.6% (7/11), and radiotherapy, 100.0% (5/5) (p = 0.001). Non-incidental strictures also had significantly higher risk of recurrence at 57.4% (27/47) vs. incidental strictures at 13.6% (6/44) (p = 0.000). The mean length of strictures was 12.5 mm (SE ± 1.7) in the recurrence group vs. 9.6 mm (SE ± 0.7) in those without recurrence (p = 0.001). The presence of ipsilateral atrophic kidney was associated with 72.2% (13/18) risk of recurrence vs. non-atrophic kidney 27.4% (20/73) (p = 0.000). The mean age of stricture was 14.5 months (SE ± 4.6) and 5.2 months (SE ± 2.1) in the recurrence and non-recurrence groups, respectively (p = 0.013).Conclusions: Balloon dilatation of benign ureteric stricture is a feasible option. Its effect can be long-lasting in selected patients, that is, non-irradiated, incidental, short strictures with normal kidneys. This will benefit patients unfit for reconstructive surgery.

Bacteria-ball in the urinary tract: a rare entity.

A bacterial mass in the urinary tract is a very rare entity. We report the first case of a bacterial ball within the urinary tract of a patient with diabetic cystopathy on long term urinary indwelling catheter. She presented with fever and gross haematuria. CT scan of abdomen and pelvis revealed a gas containing hyperdense mass within the bladder suspicious of bladder stone. The lesion was resected, and histopathology revealed a matrix of acellular materials with bacteria colony.