Small Kidney Tumors Research Articles

ASD-Net: a novel U-Net based asymmetric spatial-channel convolution network for precise kidney and kidney tumor image segmentation

Early intervention in tumors can greatly improve human survival rates. With the development of deep learning technology, automatic image segmentation has taken a prominent role in the field of medical image analysis. Manually segmenting kidneys on CT images is a tedious task, and due to the diversity of these images and varying technical skills of professionals, segmentation results can be inconsistent. To address this problem, a novel ASD-Net network is proposed in this paper for kidney and kidney tumor segmentation tasks. First, the proposed network employs newly designed Adaptive Spatial-channel Convolution Optimization (ASCO) blocks to capture anisotropic information in the images. Then, other newly designed blocks, i.e., Dense Dilated Enhancement Convolution (DDEC) blocks, are utilized to enhance feature propagation and reuse it across the network, thereby improving its segmentation accuracy. To allow the network to segment complex and small kidney tumors more effectively, the Atrous Spatial Pyramid Pooling (ASPP) module is incorporated in its middle layer. With its generalized pyramid feature, this module enables the network to better capture and understand context information at various scales within the images. In addition to this, the concurrent spatial and channel squeeze & excitation (scSE) attention mechanism is adopted to better comprehend and manage context information in the images. Additional encoding layers are also added to the base (U-Net) and connected to the original encoding layer through skip connections. The resultant enhanced U-Net structure allows for better extraction and merging of high-level and low-level features, further boosting the network’s ability to restore segmentation details. In addition, the combined Binary Cross Entropy (BCE)-Dice loss is utilized as the network's loss function. Experiments, conducted on the KiTS19 dataset, demonstrate that the proposed ASD-Net network outperforms the existing segmentation networks according to all evaluation metrics used, except for recall in the case of kidney tumor segmentation, where it takes the second place after Attention-UNet.Graphical

Comparison of transperitoneal and retroperitoneal robot partial nephrectomy for kidney tumors

Background: Surgical techniques for small kidney tumors have been developed for decades, from open to robotic surgery. There are two approaches for partial nephrectomy: transperitoneal and retroperitoneal. We divided robotic partial nephrectomy cases into transperitoneal robotic partial nephrectomy (TRPN) and retroperitoneal robotic partial nephrectomy (RRPN) and compared the outcomes.Methods: We retrospectively evaluated patients who underwent robotic partial nephrectomy at our hospital between November 2019 and May 2022. We reviewed patients’ demographic and perioperative data. Results: Seventy robotic partial nephrectomies were performed (35 TRPN and 35 RRPN). There were significant differences in operation time, estimated blood loss (EBL), tumor size, and the RENAL Nephrometry Score (RNS) between those who underwent TRPN and those who underwent RRPN. Larger tumors were noted in the TRPN group, and the RNS was higher. In contrast, the operation time was shorter, EBL was lower, and tumors were more likely to be located in the posterior and lower portions in the RRPN group than in the TRPN group.Conclusions: In our study, RRPN had advantages over TRPN in terms of operation time and EBL. However, TRPN tended to be performed rather than RRPN for tumors that were more complex in terms of size or RNS. Although the choice between RRPN and TRPN depends on the surgeon's preference, RRPN seems effective for treating small kidney tumors if selected appropriately.

Perioperative, functional, and oncologic outcomes after ablation or partial nephrectomy for solitary renal tumors: a systematic review and meta-analysis of comparative trials.

The perioperative, functional, and oncological outcomes of patients with solitary small renal tumors (SRMs) treated with ablation (AT) or partial nephrectomy (PN) remain controversial. The aim of this study was to compare the outcomes of these two surgical techniques. In April 2023, we conducted a literature search in several widely used databases worldwide, including PubMed, Embase, and Google Scholar. Review Manager was used to compare various parameters. The study was registered with PROSPERO (CRD42022377157). Our final meta-analysis included 13 cohort studies with a total of 2,107 patients. Compared to partial nephrectomy (PN), ablation (AT) had shorter hospital stays (WMD -2.37 days, 95% CI -3.05 to -1.69; p < 0.00001), shorter operating times (WMD -57.06min, 95% CI -88.92 to -25.19; p = 0.0004), less postoperative creatinine increases (WMD -0.17 mg/dL, 95% CI -0.29 to -0.05; p = 0.006), less postoperative glomerular filtration rate decreases (WMD -9.84 mL/min/1.73 m2, 95% CI -14.25 to -5.44; p < 0.0001), less postoperative new-onset chronic kidney disease (OR 0.33, 95% CI 0.16 to 0.71; p = 0.005), and less intraoperative blood loss (WMD -285.92ml, 95% CI -428.44 to -143.40; p < 0.0001). The transfusion rate was lower in the ablation group (OR 0.17, 95% CI 0.06 to 0.51; p = 0.001). The risk of local recurrence was higher in the ablation group (OR 2.96, 95% CI 1.27 to 6.89; p = 0.01), while the risk of distant metastasis was higher in the partial nephrectomy group (OR 2.81, 95% CI 1.28 to 6.18; p = 0.01). The intraoperative and postoperative complication rates were lower in the ablation group (OR 0.23, 95% CI 0.08 to 0.62; p = 0.004 and OR 0.21, 95% CI 0.11 to 0.38; p < 0.00001, respectively). However, overall survival, postoperative dialysis rate, and tumor-specific survival were not different between the two groups. Our data suggest that ablation and partial nephrectomy are equally safe and effective in the treatment of small solitary kidney tumors and are better options for patients with poor preoperative physical condition or poor renal function.

Cost-effectiveness of robotic-assisted surgery vs open surgery in the context of partial nephrectomy for small kidney tumors.

To evaluate the cost-effectiveness of robotic-assisted surgery compared to open surgery in the context of partial nephrectomy for small kidney tumor management. This is a retrospective study using data from 395 patients operated on by either robot-assisted surgery (RAPN) or by open partial nephrectomy (OPN); one hospital performed RAPN exclusively and the second hospital, OPN exclusively. Cost-effectiveness analysis was conducted from the perspective of the National Health Insurance System (NHIS) by considering the costs of the initial hospital stay and the cost of complications. Clinical outcome was defined by the avoidance of major complications during the 12months postoperatively. Major complications were absent in 82% of patients in the OPN group and 93% of patients in the RAPN group, with 11% in favor of robotic assistance (p < 0.001). The average cost per patient, including the costs of complications, were, respectively, 9637 € and 8305 € for the OPN and RAPN groups. Robotic assistance was associated with a 1332 € lower cost (p < 0.001). The incremental cost-effectiveness ratio (ICER) is estimated at -12,039 €. From the perspective of the public payer, robotic assistance was associated with a lower rate of postoperative complications and a lower average cost per patient. Robotic-assisted surgery was an efficient alternative to open surgery in partial nephrectomy. Trial registration number: NCT05089006 (October 22, 2021).

A Matched Analysis of Active Surveillance Versus Nephrectomy for T1a Small Renal Masses

While patients with a small renal mass (SRM) on active surveillance (AS) experience excellent metastasis-free survival (MFS) and cancer-specific survival (CSS), differences in overall survival (OS) observed may be explained by selection of older/comorbid patients for AS. Few studies have evaluated AS versus primary intervention in clinically balanced groups. We identified patients aged 55–75 yr with an SRM (≤4 cm, T1a) in our institutional database (2000–2020). Patients from AS and nephrectomy subgroups were matched exactly for age, sex, Eastern Cooperative Oncology Group (ECOG) performance status, biopsy status, and histology. The primary outcomes were OS and an event-free survival (EFS) composite that included OS, CSS, MFS, progression, or systemic therapy, which we tested in Cox proportional-hazards models. We identified 377 patients (205 AS, 172 nephrectomy). The cohort was balanced after matching (n = 110; mean age 64 yr, 77% male, and 75% ECOG score 0). In each arm, 47% were biopsied (predominantly clear-cell histology). The predicted 5-yr OS was 96% for the nephrectomy group and 95% for the AS group (hazard ratio for nephrectomy vs AS [HR] 0.83, 95% confidence interval [CI] 0.13–5.32; p = 0.8), with corresponding 5-yr EFS rates of 93% and 96% (HR 1.88, 95% CI 0.35–10.15; p = 0.5). Among SRM cases well matched for age and overall health status, we observed higher 5-yr OS and EFS rates for AS than previously reported; the rates were not significantly different from those after nephrectomy. The matched characteristics of our population are similar to those for treatment arms in contemporary cohorts and the results support the safety of AS in younger, healthier patients. Patient summaryWhile it has been shown that active surveillance for small kidney tumors is safe in older and more frail patients, its safety in younger, healthier patients has not been confirmed. We compared outcomes for patients aged 55–75 yr who were managed with surgery or active surveillance, and were similar in age and overall health. The probability of death after 5 years was low overall and not significantly different between the groups, suggesting that active surveillance is safe in routine clinical practice.

EO5 - Factors affecting recurrence in nephron-sparing surgery and ablative methods in small kidney tumors (pT1a): Our single center experiences

EO5 - Factors affecting recurrence in nephron-sparing surgery and ablative methods in small kidney tumors (pT1a): Our single center experiences

An Evaluation of a Web-Based Decision Aid for Treatment Planning of Small Kidney Tumors: Pilot Randomized Controlled Trial.

BackgroundSurgery is the most common treatment for localized small kidney masses (SKMs) up to 4 cm, despite a lack of evidence for improved overall survival. Nonsurgical management options are gaining recognition, as evidence supports the indolence of most SKMs. Decision aids (DAs) have been shown to improve patient comprehension of the trade-offs of treatment options and overall decision quality, and may improve consideration of all major options according to individual health priorities and preferences.ObjectiveThis pilot randomized controlled trial (RCT) primarily aims to evaluate the impact of a new web-based DA on treatment decisions for patients with SKM; that is, selection of surgical versus nonsurgical treatment options. Secondary objectives include an assessment of decision-making outcomes: decisional conflict, decision satisfaction, and an understanding of individual preferences for treatment that incorporate the trade-offs associated with surgical versus nonsurgical interventions.MethodsThree phases comprise the construction and evaluation of a new web-based DA on SKM treatment. In phase 1, this DA was developed in print format through a multidisciplinary design committee incorporating patient focus groups. Phase 2 was an observational study on patient knowledge and decision-making measures after randomization to receive the printed DA or institutional educational materials, which identified further educational needs applied to a web-based DA. Phase 3 will preliminarily evaluate the web-based DA: in a pilot RCT, 50 adults diagnosed with SKMs will receive the web-based DA or an existing web-based institutional website at urology clinics at a large academic medical center. The web-based DA applies risk communication and information about diagnosis and treatment options, elicits preferences regarding treatment options, and provides a set of options to consider with their doctor based on a decision-analytic model of benefits/harm analysis that accounts for comorbidity, age group, and tumor features. Questionnaires and treatment decision data will be gathered before and after viewing the educational material.ResultsThis phase will consist of a pilot RCT from August 2022 to January 2023 to establish feasibility and preliminarily evaluate decision outcomes. Previous study phases from 2018 to 2020 supported the feasibility of providing the printed DA in urology clinics before clinical consultation and demonstrated increased patient knowledge about the diagnosis and treatment options and greater likelihood of favoring nonsurgical treatment just before consultation. This study was funded by the National Cancer Institute. Recruitment will begin in August 2022.ConclusionsA web-based DA has been designed to address educational needs for patients making treatment decisions for SKM, accounting for comorbidities and treatment-related benefits and risks. Outcomes from the pilot trial will evaluate the potential of a web-based DA in personalizing treatment decisions and in helping patients weigh attributes of surgical versus nonsurgical treatment options for their SKMs.Trial RegistrationClinicalTrials.gov NCT05387863; https://clinicaltrials.gov/ct2/show/NCT05387863International Registered Report Identifier (IRRID)PRR1-10.2196/41451

Inclusion of Immunotherapy in the Management of Primary and Metastatic Malignant Tumours of the Kidney Including Adult Renal Cell Carcinoma: A Review and Update

Inclusion of Immunotherapy in the Management of Primary and Metastatic Malignant Tumours of the Kidney Including Adult Renal Cell Carcinoma: A Review and Update

Laparoscopic thulium fiber laser partial nephrectomy without thermal ischemia

Background. Laparoscopic partial nephrectomy (LPN) in the treatment of small kidney tumors is widespread, but the operation is associated with warm ischemia, which adversely affects the functional state of the kidney. Research is underway on methods of partial nephrectomy with a reduction of thermal ischemia or zero ischemia. The laser energy is one of the directions in the search for options for LPN. The aim of our work is to improve the LPN using a thulium laser. Materials and methods. From 2017 to 2019 a LPN was performed for 16 patients with small tumors, using the thulium laser with a wavelength of 1.94 ^m. There were men 7 (43.8 %), women — 9 (56.2 %), average age was 51 (39—68) years, average kidney tumor size was 24.9 (15—40) mm. The evaluation of laser resectability on the RENAL scale was carried out using 3D modeling. We used the laparoscopic laser aspirator-irrigator to reduce smoke generation during the procedures. Results. The average time of LPN using a fiber thulium laser was 97.5 (70—131) min. The time for kidney resection was 25.6 (10—40) min. 14 (87.5 %) procedures performed completely without warm ischemia. The average blood loss during surgery was 111.3 (50—250) ml. The duration of postoperative treatment was 7.1 (5—9) days. A positive surgical margin was not observed. Histological examination revealed renal cell carcinoma in 14 (87.5 %) patients, G2 — 10 (71.4 %), G2 — 4 (28.6 %). When examining glomerular filtratoin rare in the operated patients after procedures, no changes were observed. Conclusion. The use of the thulium laser for LPN allows perform the procedure without warm ischemia in selected patients with a predominantly extrarenal tumor location. The use of a laparoscopic instrument the laser aspirator-irrigator with a drip water supply and simultaneous aspiration reduced smoke generation during laser thulium resection, the operation performed under conditions of improved visualization, which prevents the danger of a positive surgical edge. Further monitoring of the results of applying the method of thulium laser LPN is required.

Limitations of Available Studies Prevent Reliable Comparison Between Tumour Ablation and Partial Nephrectomy for Patients with Localised Renal Masses: A Systematic Review from the European Association of Urology Renal Cell Cancer Guideline Panel

The European Association of Urology (EAU) Renal Cell Carcinoma (RCC) Guideline Panel performed a protocol-driven systematic review (SR) on thermal ablation (TA) compared with partial nephrectomy (PN) for T1N0M0 renal masses, in order to provide evidence to support its recommendations. The Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines were followed, and only comparative studies published between 2000 and 2019 were included. Twenty-six nonrandomised comparative studies were included, recruiting a total of 167 80 patients. Risk of bias (RoB) assessment revealed high or uncertain RoB across all studies, with the vast majority being retrospective, observational studies with poorly matched controls and short follow-up. Limited data showed TA to be safe, but its long-term oncological effectiveness compared with PN remains uncertain. A quality assessment of pre-existing SRs (n=11) on the topic, using AMSTAR, revealed that all SRs had low confidence rating, with all but two SRs being rated critically low. In conclusion, the current data are inadequate to make any strong and clear conclusions regarding the clinical effectiveness of TA for treating T1N0M0 renal masses compared with PN. Therefore, TA may be cautiously considered an alternative to PN for T1N0M0 renal masses, but patients must be counselled carefully regarding the prevailing uncertainties. We recommend specific steps to improve the evidence base based on robust primary and secondary studies. Patient summaryIn this report, we looked at the literature to determine the effectiveness of thermoablation (TA) in the treatment of small kidney tumours compared with surgical removal. We found that TA could cautiously be offered as an option due to many remaining uncertainties regarding its effectiveness.

Positive margins after partial nephrectomy in renal cell carcinoma: Oncological outcomes of conservative management after long-term follow-up

IntroductionPartial nephrectomy (PN) is the standard treatment for small and localized kidney tumors (cT1). One of the controversial aspects regarding this technique is the management of affected/positive resection margins. We present the long-term oncological results in patients with PSM after PN managed conservatively. Material and methodsThere were 207 PN performed in our center between 1990 and 2011. 17 patients presented PSM. 2 patients were excluded from the study due to completion nephrectomy afterwards. Follow-up was done with abdominal contrast-enhanced computed tomography every 6 months for the first 2 years and subsequently, once a year. Cancer-specific survival and disease-free survival were calculated with the Kaplan–Meier method. ResultsThe median age was 62 years (RIQ: 55–71) and the mean tumor size was 34.8 (10–77) mm. Histopathological results were: 6 (40%) clear cell RCC, 4 (26.7%) papillary, 3 (20%) chromophobe and 2 (13.3%) oncocytic. The pathologic stages were: 11 (73.3%) pT1a, 1 (6.7%) pT1b and 3 (20%) pT3a. The median follow-up was 84 months (IQR 72–120). 2 patients had metastatic recurrence and this was the cause of death. The first one had recurrence at 112 months and the second one at 59. 5-year CSS and RFS were 87.5% and 93.3% respectively. ConclusionsIn our experience, patients with PSM after PN can be managed conservatively with satisfactory long-term oncological outcomes.

Personalised medicine in renal cell tumours

The extensive use of abdominal imaging reveals an increasing number of small and asymptomatic kidney tumours, for which primary treatment versus observation strategies need to be discussed. Elaborate surgical techniques and a variety of systemic treatment options are available for patients with localised and advanced tumours. This necessitates a demanding and complex individualised decision-making process. A better understanding of tumour biology including validated biomarkers is therefore essential in order to improve diagnostics, prognostic evaluation and therapeutic strategies.Renal cell tumours are currently subdivided into 16 histological subtypes, each characterised by specific genetic changes. As tumour aggressiveness differs significantly, knowledge of these distinct subtypes is important for adequate treatment choice and follow-up. Molecular markers may facilitate an exact diagnosis and will further differentiate the individual prognosis within each subtype, which is already possible for clear cell renal cell carcinoma (RCC). This will lead to individualised follow-up protocols and a better selection of patients benefitting from observational or adjuvant strategies after surgery.For metastatic tumours, the number of systemic treatment options targeting specific cellular signal or communication pathways has increased tremendously. Valid predictive biomarkers for differential treatment are not available to date. However, there is promising evidence of correlations between molecular signatures and treatment response to tyrosine kinase inhibitors or checkpoint inhibitors. Biomarkers will most likely supersede clinical scores for individual treatment selection in the near future.Prospective multicentre studies are needed so that promising biomarkers can be implemented in daily clinical practice in due consideration of existing insights from the tumour biology of the distinct RCC subtypes. This is essential for further improvement of diagnosis and treatment.

Márgenes positivos tras nefrectomía parcial en carcinoma de células renales: seguimiento a largo plazo y resultados oncológicos con manejo conservador

IntroductionPartial nephrectomy (PN) is the standard treatment for small and localized kidney tumours (cT1). One of the controversial aspects regarding this technique is the management of affected/positive resection margins. We present the long-term oncological results in patients with PSM after PN managed conservatively. Material and methodsThere were 207 PN performed in our centre between 1990 and 2011. 17 patients presented PSM. 2 patients were excluded from the study due to completion nephrectomy afterwards. Follow-up was was done with abdominal contrast-enhanced computed tomography every 6 months for the first 2 years and subsequently, once a year. Cancer-specific survival and disease-free survival were calculated with the Kaplan-Meier method. ResultsThe median age was 62 years (RIQ: 55-71) and the mean tumour size was 34.8 (10-77) mm. Histopathological results were: 6 (40%) clear cell RCC, 4 (26.7%) papillary, 3 (20%) chromophobe and 2 (13.3%) oncocytic. The pathologic stages were: 11 (73.3%) pT1a, 1 (6.7%) pT1b and 3 (20%) pT3a. The median follow-up was 84 months (IQR 72-120). 2 patients had metastatic recurrence and this was the cause of death. The first one had recurrence at 112 months and the second one at 59. 5-year CSS and RFS were 87.5% and 93.3% respectively. ConclusionsIn our experience, patients with PSM after PN can be managed conservatively with satisfactory long-term oncological outcomes.

Toward Semi-autonomous Cryoablation of Kidney Tumors via Model-Independent Deformable Tissue Manipulation Technique.

We present a novel semi-autonomous clinician-in-the-loop strategy to perform the laparoscopic cryoablation of small kidney tumors. To this end, we introduce a model-independent bimanual tissue manipulation technique. In this method, instead of controlling the robot, which inserts and steers the needle in the deformable tissue (DT), the cryoprobe is introduced to the tissue after accurate manipulation of a target point on the DT to the desired predefined insertion location of the probe. This technique can potentially reduce the risk of kidney fracture, which occurs due to the incorrect insertion of the probe within the kidney. The main challenge of this technique, however, is the unknown deformation behavior of the tissue during its manipulation. To tackle this issue, we proposed a novel real-time deformation estimation method and a vision-based optimization framework, which do not require prior knowledge about the tissue deformation and the intrinsic/extrinsic parameters of the vision system. To evaluate the performance of the proposed method using the da Vinci Research Kit, we performed experiments on a deformable phantom and an ex vivo lamb kidney and evaluated our method using novel manipulability measures. Experiments demonstrated successful real-time estimation of the deformation behavior of these DTs while manipulating them to the desired insertion location(s).

The role of ablative technologies in the treatment of small kidney tumors: an overview of the current state of the problem

The ablative treatment provides a minimally invasive model for the surgical removal of small kidney tumors, which reduces the risk and complications that are traditionally associated with open or laparoscopic partial nephrectomy. Among the main methods, the cold radiofrequency ablation is isolated; laparoscopic, percutaneous ablation; high intensity focused ultrasound.

A single centre experience of zero-ischaemia laparoscopic partial nephrectomy in Ireland.

Nephron-sparing surgery in the form of partial nephrectomy is increasingly becoming the standard of care in patients with small renal tumours. Oncological outcomes for partial nephrectomy are equivalent to radical nephrectomy, however, clamping of the hilar vessels to allow resection of tumours during partial nephrectomy may cause ischaemic damage to the kidney and result in long-term renal impairment. We carried out a retrospective review of 43 patients undergoing laparoscopic partial nephrectomy (LPN) and assessed functional and oncological outcomes. The operative technique initially utilised a thulium laser, with later cases using the LigaSure™ vessel sealing device. All patients underwent preoperative cross sectional imaging and anatomical classification accordingly. Forty three patients underwent LPN in our unit from 2006 to 2014. The mean (range) tumour diameter on preoperative cross sectional imaging was 28.2 (12-49)mm. All cases had a warm ischaemia time of zero, as hilar vessels were not clamped in any case. The mean (range) preoperative estimated glomerular filtration rate (eGFR) was 73 (37 to >90) ml/min/1.73m2 and was not significantly different to the post-operative mean (range) eGFR of 71 (31 to >90) ml/min/1.73m2. 34 (79%) of the tumours were found to be malignant. Positive surgical margins were found in one case. The mean (range) follow-up time in our cohort was 61.6 (24-127) months and no patient has had a local or distant recurrence. Zero ischaemia laparoscopic partial nephrectomy appears to be a safe and oncologically satisfactory procedure for the management of small localised kidney tumours.

MP41-04 PREOPERATIVE PROTEINURIA IS ASSOCIATED WITH WORSE RENAL OUTCOMES IN PATIENTS UNDERGOING ELECTIVE PARTIAL NEPHRECTOMY

INTRODUCTION AND OBJECTIVES: Proteinuria is considered an important prognostic indicator for progression of chronic kidney disease (CKD) and mortality. Our goal was to investigate the significance of preoperative proteinuria in a cohort of patients without preexisting CKD undergoing elective partial nephrectomy (PN) for T1a tumors. METHODS: We reviewed a prospectively collected IRB approved database of 837 patients undergoing nephrectomy between 1/2007 and 12/2014, at our institution. Patients with preoperative GFR >60ml/min/1.73m and available preoperative urinalysis receiving elective PN for a pathologic T1a tumor were included. Proteinuria was defined as 30mg/dL. Postoperative GFR was measured at a minimum of 3 months. GFR categories were created based on Kidney Disease: Improving Global Outcomes guidelines. Demographic, tumor specific, and intraoperative characteristics as well as postoperative renal outcomes at last follow up were analyzed. RESULTS: We included 298 patients, 25 (8.4%) of whom had preoperative proteinuria, with a mean follow up of 34 months. There were no significant differences in age, BMI, comorbidities, operative time, EBL, ischemia time, or tumor size between the two groups. Patients with pre-existing proteinuria were more likely to be black (p1⁄40.02) and have a lower pre-op GFR (81.4 vs. 87.3 ml/min, p1⁄40.05). The mean decrease in GFR after PN in those with preoperative proteinuria was 19.7 vs. 9.4 ml/min in the control group (p1⁄40.01) (Table 1). After PN, 52% of patients in the proteinuria group developed CKD vs 13% in the group without proteinuria (p1⁄4<.001) (Table 2). CONCLUSIONS: In patients without pre-operative CKD undergoing elective PN, the presence of proteinuria is associated with larger decreases in GFR and higher probability of progression to CKD after surgery. Assessment of proteinuria preoperatively may aid in proper treatment selection for patients with small kidney tumors.

Eraser Laser Enucleation of the Prostate: Technique and Results

BackgroundEraser, a 1318-nm diode laser, has been used for 15 yr for resection of lung metastases. It was recently introduced in urology for small kidney tumors and for the treatment of benign prostatic obstruction. ObjectiveTo demonstrate on video our technique of Eraser laser enucleation of the prostate (ELEP) and report our experience. Design, setting, and participantsFrom June 2010 to October 2011, 43 consecutive patients were prospectively evaluated. All of them had lower urinary tract symptoms suggestive of benign prostatic obstruction and a mean prostate size of 59.9ml (range: 34–89ml) on transrectal ultrasound. Their mean prostate-specific antigen value was 3.4 ng/ml (range: 0.8–5.0 ng/ml); mean maximum flow rate (Qmax), 6.9ml/s (range: 2–11ml/s); mean International Prostate Symptom Score (IPSS), 25.9 (range: 18–32); and mean postvoid residual (PVR), 170.5ml (range: 60–330ml). Surgical procedureThe details of the technique are shown on video. Outcome measurements and statistical analysisSuccess was defined as patients being able to void with improved IPSS, Qmax, PVR volume, and ameliorated quality of life. Results and limitationsThe mean operating time was 67.0±11.43min. Mean serum hemoglobin was 15.1±0.87g/l before, and 14.39±0.94g/l after surgery. Mean blood loss was 115.90±98.12ml. No blood transfusions were required. All patients had their catheters removed within 2 d and were able to void spontaneously after this time. Significant improvements were noted in Qmax, quality of life, IPSS, and PVR volume from baseline to each follow-up time point.Based on the validated Clavien-Dindo system, we observed one grade 1d complication, one grade 2 complication, and one grade 3b complication. ConclusionsELEP is a safe and reproducible method for relieving bladder outflow obstruction and lower urinary tract symptoms. Its advantages include minimal blood loss, short catheterization time, and a brief hospital stay.

Anatrophic nephrotomy as nephron-sparing approach for complete removal of intraparenchymal renal tumors

Partial nephrectomy for small kidney tumors has increased in the last decades, and the approach to non-palpable endophytic tumors became a challenge, with larger chances of positive margins or complications. The aim of this study is to describe an alternative nephron-sparing approach for small endophytic kidney tumors through anatrophic nephrotomy. A retrospective analysis of patients undergoing partial nephrectomy at our institution was performed and the subjects with endophytic tumors treated with anatrophic nephrotomy were identified. Patient demographics, perioperative outcomes and oncological results were evaluated. Among the partial nephrectomies performed for intraparenchymal tumors between 06/2006 and 06/2010, ten patients were submitted to anatrophic nephrotomy. The mean patient age was 42 yrs, and the mean tumor size was 2.3 cm. Mean warm ischemia time was 22.4 min and the histopathological analysis showed 80% of clear cell carcinomas. At a mean follow-up of 36 months, no significant creatinine changes or local or systemic recurrences were observed. The operative technique described is a safe and effective nephron-sparing option for complete removal of endophytic renal tumors.

First Prize: A Phantom Model as a Teaching Modality for Laparoscopic Partial Nephrectomy

To evaluate a materials model for laparoscopic ultrasound identification and partial nephrectomy of kidney tumors. Five urology fellows performed laparoscopic ultrasonography (LUS) examination of the tumor model, and the time for identification was recorded. After identifying the tumor, they performed a laparoscopic partial nephrectomy using the target tumor with measurement of operative parameters. They completed a questionnaire and rated the quality of the renal tumor model on a 5-point Likert scale. The participants were able to identify 49 tumors by LUS (98%). The mean time to identify the renal tumors by LUS was 1.12 minutes ± 0.93 standard deviation (SD). A partial nephrectomy was successfully completed on 49 tumor models (98%). The mean resection time was 7.69 minutes ± 3.8 SD. All of the participants considered that this model was helpful in the practice of LPN. The fellows would recommend this model as a teaching tool for residents/fellows to perform tumor imaging by LUS and for practicing LPN in a simulated environment. We have developed a unique model that simulates small kidney tumors that can be used for training surgeons in the clinical skills of laparoscopic partial nephrectomy.