The European Urology Residents Education Programme Hands-on Training Format: 4 Years of Hands-on Training Improvements from the European School of Urology.

BACKGROUND: The European School of Urology (ESU) started the European Urology Residents Education Programme (EUREP) in 2003 for final year urology residents, with hands-on training (HOT) added later in 2007. OBJECTIVE: To assess the geographical reach of EUREP, trainee demographics, and individual quality feedback in relation to annual methodology improvements in HOT. DESIGN, SETTING, AND PARTICIPANTS: From September 2014 to October 2017 (four EUREP courses) several new features have been applied to the HOT format of the EUREP course: 1:1 training sessions (2015), fixed 60-min time slots (2016), and standardised teaching methodology (2017). The resulting EUREP HOT format was verified by collecting and prospectively analysing the following data: total number of participants attending different HOT courses; participants' age; country of origin; and feedback obtained annually. RESULTS AND LIMITATIONS: A total of 796 participants from 54 countries participated in 1450 HOT sessions over the last 4 yr. This included 294 (20%) ureteroscopy (URS) sessions, 237 (16.5%) transurethral resection (TUR) sessions, 840 (58%) basic laparoscopic sessions, and 79 (5.5%) intermediate laparoscopic sessions. While 712 residents (89%) were from Europe, 84 (11%) were from non-European nations. Of the European residents, most came from Italy (16%), Germany (15%), Spain (15%), and Romania (8%). Feedback for the basic laparoscopic session showed a constant improvement in scores over the last 4 yr, with the highest scores achieved last year. This included feedback on improvements in tutor rating (p=0.017), organisation (p<0.001), and personal experience with EUREP (p<0.001). Limitations lie in the difficulties associated with the use of an advanced training curriculum with wet laboratory or cadaveric courses in this format, although these could be performed in other training centres in conjunction with EUREP. CONCLUSIONS: The EUREP trainee demographics show that the purpose of the course is being achieved, with excellent feedback reported. While European trainees dominate the demographics, participation from a number of non-European countries suggests continued ESU collaboration with other national societies and wider dissemination of simulation training worldwide. PATIENT SUMMARY: In this paper we look at methodological improvements and feedback for the European Urology Residents Education Programme hands-on-training over the last 4 yr.

The Ability of Prostate Health Index (PHI) to Predict Gleason Score in Patients With Prostate Cancer and Discriminate Patients Between Gleason Score 6 and Gleason Score Higher Than 6-A Study on 320 Patients After Radical Prostatectomy.

AIM: The purpose of this study was to investigate the Prostate Health Index as a marker for tumor aggressiveness in prostate biopsy and the optimization of indication for treatment options. METHODS: Our cohort consisted of 320 patients indicated for radical prostatectomy with preoperative measurements of total prostate-specific antigen, free prostate-specific antigen, [-2]proPSA, calculated %freePSA, and Prostate Health Index. The Gleason score was determined during biopsy and after radical prostatectomy. Using the Gleason score, we divided the group of patients into the 2 subgroups: Gleason score ≤6 and Gleason score >6. This division was performed according to the biopsy Gleason score and according to the postoperative Gleason score. We compared total prostate-specific antigen, [-2]proPSA, %freePSA, and Prostate Health Index in the subgroups Gleason score ≤6 and Gleason score >6 after biopsy and the definitive score. RESULTS: On evaluation of the subgroups created by Gleason score ≤6 and Gleason score >6, we observed agreement between biopsy Gleason score and definitive Gleason score in only 45.3% of cases. Of the calculated biopsy, Gleason score ≤6 and Gleason score >6 subgroups, [-2]proPSA, and Prostate Health Index ( P = .0003 and P = .0005) were statistically significant. Of the definitive Gleason score ≤6 and Gleason score >6 subgroups, Prostate Health Index, [-2]proPSA, %freePSA, and PSA ( P < .0001, P < .0001, P = .0003, and P = .0043) were statistically significant. The best area under the curve value (0.7496) was achieved by Prostate Health Index when the subgroups were established according to the postoperative Gleason score. CONCLUSION: Prostate Health Index is the best of the tested markers for the categorization of Gleason score 6 tumors and for facilitating the management of patients with prostate cancer. Prostate Health Index can be a helpful marker for indication of active surveillance or radical prostatectomy. Prostate health index can also simplify the decision of whether to perform nerve-sparing radical prostatectomy.

Morphological Characterization of Papillary Renal Cell Carcinoma Type 1, the Efficiency of Its Surgical Treatment.

AIM: Papillary renal cell carcinoma type 1 (pRCC1) represents the second most common type of malignant renal epithelial tumour. The origin of its characteristic appearance, its growth mechanism, and the long-term efficiency of its surgical treatment remain uncertain. Our aim was to determine typical characteristics of surgically treated pRCC1. METHODS: pRCC1 was verified in 83 of 1,629 (5.1%) kidney tumours surgically treated in the period of January 2007-January 2016. The clinical and radiological characteristics, type of surgery, histopathology results and follow up data were recorded. Spearman correlation, Kruskal-Wallis analysis of variance, Fisher's exact, and chi-square test were used to analyse appropriate variables. The overall survival rate was evaluated using the Gehan-Wilcoxon test and the Cox proportional hazards model. RESULTS: The mean tumour size was 52.0 mm (15-180); 98.8% of the tumours showed a spherical shape and in 82.1%, exophytic growth was observed. Partial nephrectomy was performed in 80.7%. A majority (81.9%) were classified as pT1. Tumours, 89.2% of them, belonged to Fuhrman grade 1 or 2. The mean follow-up was 46.8 months. The overall survival was associated with pT category (p ≤ 0.0001). CONCLUSIONS: Typical signs of pRCC1 are a spherical shape, exophytic growth and low Fuhrman's grade. More than three-fourths of pRCC1 could be treated by the nephron-sparing surgery.

Safety and Feasibility of Laparoscopic Nephrectomy for Big Tumors (≥ 10 cm): A Retrospective Multicentric Study.

OBJECTIVE: Evaluate the feasibility of laparoscopic nephrectomy for big tumors. MATERIAL AND METHODS: Data from 116 patients were retrospectively collected from 16 tertiary centres. Clinical and operative parameters, tumor characteristics, pre- and postoperative parameters, and renal function before and after surgery were analyzed. RESULTS: Mean age and body mass index were 61 years and 27.8 kg/m(2), respectively. Males represented 63.8% of patients, and 54.4% presented symptoms at diagnosis. Median tumor size was 11 cm, and 75% of the cases were performed by expert surgeons. Median operative time and blood loss were 180 minutes and 200 mL respectively. Conversion to open surgery was necessary in 20.7% of cases. Intraoperative complications related to massive hemorrhage occurred in 16.4% of patients, resulting in open conversion in 62.5%. Major postoperative complications occurred in only 10 patients (8.6%). In univariate analysis, intraoperative complications, age, and blood loss were predictive factors of conversion to open surgery. Positive surgical margins occurred in 6 patients (5.2%). None of them presented a local recurrence. Predictive factors of recurrence or progression were lymph node invasion, metastases, and Furhman grade. CONCLUSION: Laparoscopic nephrectomy for tumors > 10 cm can be performed safely. Complication rate and positive surgical margins are similar to open surgery. In experienced hands, the benefit of a mini invasive surgery remains evident.

Surgical treatment of kidney tumors - contemporary trends in clinical practice.

INTRODUCTION: The aim of this article is to generally describe the roles of main surgical modalities in treatment of renal tumors, especially in the CT1a category in clinical practice. Surgical modalities include the following: laparoscopic or open resection (LR, OR) and laparoscopic or open nephrectomy (LN, ON). Representation of these methods has been changing over years due to improved operative skills and equipment and due to a shift of tumors to the lower T categories. MATERIAL AND METHODS: The sources of data were surgeries performed for renal tumors at the institution of the main author during the period 2002 to III/2016, reaching a total of 2204 cases (546 ONs, 647 LNs, 668 ORs and 343 LRs). Patients indicated for percutaneous ablative therapy or active surveillance were not included. RESULTS: During the whole period, the proportions of methods were: ONs 24.8%, LNs 29.4%, ORs 30.3%, LRs 15.6%. But during the years 2014 - III/2016, these changed to 12.6%:26.3%:31.6%:29.4% (in cT1a 1.7%:8.3%:37.8%:52.2%). Category cT1a constitutes in the years 2007 - III/2016 41.3%, in 2014 - III/2016 50.9%. CONCLUSIONS: Resections and minimally invasive approaches are being performed more frequently and are the preferred methods in surgical treatment of kidney tumors. Resection is now indicated in about 60% of cases (open vs. laparoscopic resection are used nearly equally with a slight tendency for laparascopic predomination). In the cT1a category (amounting to approximately 50% of all surgically treated tumors), resection is possible in about 85-90% of cases.

Laparoscopic urinary bladder diverticulectomy combined with photoselective vaporisation of the prostate.

INTRODUCTION: Pseudodiverticulum of the urinary bladder is mostly a complication of subvesical obstruction (SO). The gold standard of treatment was open diverticulectomy with adenectomy. A more contemporary resolution is endoscopic, in two steps: the first transurethral resection of the prostate (TURP), the second laparoscopic diverticulectomy (LD). AIM: To present a one-session procedure - photoselective vaporisation of the prostate (PVP) with LD. MATERIAL AND METHODS: From 1/2011 to 6/2014, 14 LDs were performed: 1 LD only, 1 with laparoscopic radical prostatectomy, 12 combined with treatment of benign prostatic hyperplasia (BPH), 4 cases of TURP and LD in the second period. In 8 cases, PVP and LD in one session were combined. These 8 cases are presented. 3D CT cystography was used as a gold standard for assessment of diverticulum. RESULTS: The mean age was 66.5 ±5.5 (57.3-75.1) years, the mean size of the diverticulum 61.8 ±22.1 (26-90) mm. The procedure starts in the lithotomy position. It includes PVP and stenting of the ureter(s). Changing of position and laparoscopy follows: four ports, transperitoneal extravesical approach. Photoselective vaporisation of the prostate was performed using the Green Light Laser HPS (1x) or XPS with cooled fibre MoXy (7x). The mean delivered energy in PVP was 205.1 ±106.4 (120-458) kJ. The mean time of operation was 165.0 ±48.5 (90-255) min. No postoperative complications were observed. One patient underwent TUR incision after 1 year for sclerosis of the bladder neck. CONCLUSIONS: Pseudodiverticulum of the urinary bladder (with or without SO) is a relatively rare disease. One session of PVP (Green Light Laser XPS, MoXy fibre) and laparoscopic (transperitoneal extravesical) diverticulectomy is the preferred method for treatment of subvesical obstruction due to BPH and bladder diverticulum at our institution.

Genetic testing of leiomyoma tissue in women younger than 30 years old might provide an effective screening approach for the hereditary leiomyomatosis and renal cell cancer syndrome (HLRCC).

We have studied the viability of targeted molecular screening for the identification of female patients with hereditary leiomyomatosis and renal cell cancer (HLRCC) syndrome. Affected patients harbor a germ-line heterozygous mutation of the fumarate hydratase (FH) gene. Clinically, some patients present with aggressive renal cell carcinoma. Concerning women, in almost all cases, this is preceded by symptomatic uterine leiomyoma. We aimed to identify women operated on for symptomatic leiomyoma by the age of 30. Archived paraffin-embedded leiomyoma tissue was tested for the FH gene mutation in 14 cases. Two patients with multiple leiomyomas and with the confirmed germ-line mutations c.1433_1434dupAAA, p.(Lys477dup) and c.953A>T, p.(His318Leu) were identified and enrolled in a surveillance program. Statistically significant correlation between the presence of multiple uterine leiomyomas (more than seven in our experience) and the FH gene mutation was found. The immunohistochemical expression pattern, of simultaneous FH absence and S-(2-succino)cysteine (2SC) positivity, correlated with the results of the molecular genetic study in only one case. The histomorphologically simultaneous detection of enlarged nucleoli with a clear halo of leiomyocyte nuclei, their fibrillary cytoplasm, the presence of eosinophilic globules, and staghorn vessels proved to be only a partially sensitive indicator of HLRCC-associated leiomyoma and fully correlated with immunohistochemistry and molecular genetic study only in one case. Molecular genetic testing is presently the only reliable diagnostic tool able to identify HLRCC patients. The sensitivity and specificity of the presence of multiple leiomyomas in women with the FH gene mutation who are younger than 30 years old should be confirmed in larger scale studies. The applied targeted molecular screening protocol proved to be effective, resulting in identification of two positive patients out of fourteen tested individuals.

Position of laparo-endoscopic single-site surgery nephrectomy in clinical practice and comparison (matched case-control study) with standard laparoscopic nephrectomy.

INTRODUCTION: One way how to reduce morbidity and improve cosmesic of kidney surgery is single site laparoscopy. Relatively well described concept but without defined position in clincal practise. AIM: To report of institutional experience with laparoendoscopic single-site surgery (LESS) nephrectomy (NE) and compare (matched case-control study) it with that of standard laparoscopic NE (LNE). MATERIAL AND METHODS: In the period 8/2011 to 10/2013, we performed 183 mini-invasive NE (132 tumours, 51 benign aetiology); 45 of them (24.6%) were LESS, the rest LNE. The main but not absolute indications for LESS were: non-obese men, and less advanced tumours. In 13 patients undergoing LESS-NEs (28.9%) there was a transumbilical approach. For the rest, a pararectal incision was performed and an accessory port was added in 31.1% (14) - 2/22 (9.1%) left sided, 12/23 (52.2%) right sided. Twenty-four LESS-NE were performed by a more experienced surgeon (mean operation time (MOT) 73.1 min), 21 LESS-NE by 4 other surgeons (MOT 132.8 min). These 24 were compared with 43 LNE done by the same surgeon before the period of LESS (1/2007-8/2011) and with similar characteristics of cases (body mass index (BMI) ≤ 35 kg/m(2), less advanced tumour). RESULTS: We found no statistically significant differences in any of the parameters studied. The MOT 73.1 min vs. 75.0 min (p = 0.78), BMI 27.4 kg/m(2) vs. 29.2 kg/m(2) (p = 0.08), blood loss 54.7 vs. 39.2 (p = 0.47). Complications (4.2% vs. 11.6%) were only of internal character in origin. No conversion in either group. In LESS-NE, staplers were used more frequently (more expensive than clips) for division of renal hilar vessels (70.8% vs. 51.2%). The mean price of LESS-NE was €367 higher. CONCLUSIONS: The LESS NE performed by an experienced surgeon is a safe and efficient method for the surgical treatment of both malignant and benign renal conditions in patients with BMI < 30 kg/m(2) and with low-stage tumours. The LESS NE is more expensive compared to LNE.

Laparoscopic adrenalectomy for metachronous ipsilateral metastasis following nephrectomy for renal cell carcinoma.

INTRODUCTION: Although laparoscopic adrenalectomy (LA) is considered as a gold standard approach for adrenalectomy, there are minimal data describing options and outcomes of LA after previous ipsilateral nephrectomy (PIN). AIM: To describe our results in a group of patients who underwent LA after PIN. MATERIAL AND METHODS: From August 2004 to October 2012 we performed at our institution 88 LA. Of this amount we performed 5 LA for metachronous metastasis of renal cell carcinoma (RCC) after PIN. This group was compared to a group without previous nephrectomy. RESULTS: The group comprised 4 men (80%) and 1 woman (20%); the mean age at the time of surgery was 66.8 ±8.5 (range: 60-77) years; the mean period between nephrectomy and adrenalectomy was 5.2 (range: 1.5-14) years; the operating time was longer in patients after PIN for 7 min; the mean blood loss was higher by 22 ml; duration of hospitalization was shorter by 1.3 days, paradoxically, compared with patients without PIN. There was no need for conversion to open surgery and we did not observe any other complications. CONCLUSIONS: Laparoscopic adrenalectomy for metastasis of RCC after PIN is a technically feasible method in selected patients and it is associated with no significant differences in perioperative data in comparison with the group without prior nephrectomy. The patients benefit from minimally invasive surgery. The performance has required an experienced laparoscopic surgeon.

Managing urine leakage following laparoscopic radical prostatectomy with active suction of the prevesical space.

INTRODUCTION: Urine leakage following laparoscopic radical prostatectomy (LRP) is a possible complication that may herald chronic urine incontinence. Intraoperative measures aiming to prevent this is not standardised. AIM: Presentation of experience with active suction of the prevesical space in managing postoperative urine leakage. MATERIAL AND METHODS: At the Department of Urology, where laparoscopy of the upper abdomen and open RP were performed, a protocol for extraperitoneal LRP was established in 8/2008. Until 5/2011, 154 LRPs have been performed. Urine leakage from a suction drain appeared in 9 cases (5.8%). Permanent active suction (with a machine for Büllae thoracic drainage) of the prevesical space with negative pressure of 7-12 cm of H2O was started immediately. RESULTS: Urine leakage started after a mean of 0.9 (0-2) days postoperatively and stopped after a mean of 8.1 (15-42) days. Leakage stopped with only suctioning in 7 cases. In one case, open re-anastomosis was performed on the 7(th) postoperative day (POD). In another case, ineffective active suction was replaced on the 10(th) POD by needle vented suction without effect and the leakage stopped following gradual shortening of the drain up to the 15(th) POD. CONCLUSIONS: Active suction of the prevesical space seems to be an effective intervention to stop postoperative urine leakage after laparoscopic radical prostatectomy.

Three-tesla MRI biphasic angiography: a method for preoperative assessment of the vascular supply in renal tumours: a surgical perspective.

PURPOSE: The new generation of 3TMRI has improved spatial and time resolutions, which are favourable in imaging of the renal vasculature. In this study, we have compared the imaging findings of the renal blood vessels using 3TMRI and CT with intraoperative assessment of the renal vasculature as gold standard. METHODS: This prospective study was approved by the local ethical committee. Between 4/2011 and 12/2011, 80 patients with renal tumours underwent 3TMRA (angiography) (Magnetom SKYRA 3T, Siemens). Twenty of the patients were also examined with CT AG. The results of the CTA- and MRA-imaging studies were correlated with the intraoperative assessment of the renal vessels. RESULTS: Seventy patients (87.5 %) had a detailed intraoperative assessment of the renal vessels. The sensitivities for CTA and MRA were 88.2 and 88.6 %, respectively. All discrepancies between imaging studies and intraoperative findings were due to inability to identify small polar vessels. The results of MRA were concordant with CTA in 85.0 % of cases. The (three) discrepancies between MRI and CT were due to failure of MRI in identifying small polar vessels. CONCLUSIONS: (1) 3TMRA gives detailed information about the renal vasculature including its topographical anatomy. (2) With MRI, small aberrant vessels are more frequently missed than with CTA. (3) CTA remains the gold standard. However, MRA may be used for planning of laparoscopic operations. (4) The quality of the 3D reconstruction is highly depending on the skills of the radiologist.

Complete laparoscopic nephroureterectomy with intravesical lockable clip.

INTRODUCTION: We present a cohort of patients with low-stage pelviureteric neoplastic disease who underwent complete laparoscopic nephroureterectomy (CLNUE) with intravesical lockable clip (IVLC). Due to the absence of a standard technique of NUE, the study was not randomized. MATERIALS: From 1/2010 to 1/2012, 21 patients were subjected to CLNUE-IVLC. The first step was transurethral excision of the ureterovesical junction with Collin's knife deep into the paravesical adipose tissue. The ureter was grasped with biopsy forceps and the distal end of the ureter was occluded with lockable clip. The applicator was introduced through a 5 mm port inserted as an epicystostomy. The patients were rotated to flank position and CLNUE followed. The endoscopically introduced clip on the distal ureter is proof of completion of the total ureterectomy. RESULTS: The mean operation time was 161 (115-200) min. In four (19.0%), the application of the clip failed and CLNUE was completed with non-occluded ureter. In three cases, subsequent laparoscopic nephrectomy was converted to open surgery. In two cases, the distal ureterectomy was completed with pluck technique through a lower abdominal incision that was also used for extraction of the specimen. There were four complications (Clavien II 2x, IIIb, V). Follow-up was available for all - mean 10.6 (range: 0-25) months. One died of disease generalization within 11 months. CONCLUSION: CLNUE-IVLC is fast and safe. If needed, the endoscopic phase can be switched to open NUE. Disadvantages include: the need to change the position of the patient, the risk of inability to apply the clip on the distal ureter, and the risk of an unclosed defect of the urinary bladder.

Tubulocystic renal carcinoma: a clinical perspective.

INTRODUCTION: Tubulocystic renal carcinoma (TCRC) is a recently described neoplastic entity. To date, clinicopathological features on less than hundred cases of these rare tumours have been characterized exclusively in the pathological literature. Herein, we present five additional cases emphasizing clinical aspects on these rare renal neoplasms. MATERIAL AND METHOD: Cases diagnosed as TCRC were retrieved and reviewed from the routine and consultation files of the Pilsen tumour registry comprising over 20,000 cases of renal tumours. RESULTS: All patients were men, mean age 56 years (range 29-70). Features on computed tomography (CT) were in two cases Bosniak III, one IV and two were solid tumours. In four patients, nephrectomy was performed, and one patient underwent resection. At the time of surgery, two patients had metastases. In one case, both primary tumour and metastases were active on FDG positron emission tomography (PET)/CT. Both patients with metastatic disease were treated with sunitinib with partial response. One patient died 26 months postoperatively and the other patient is alive 5 months after surgery. Three patients with localized tumours are without evidence of disease 31, 28 and 7 months after surgery. In one case, the resected tumour was histologically combined with a papillary renal cell carcinoma (PRCC). CONCLUSION: TCRC occurs predominantly in men with a wide age range. TCRC frequently displays a cystic component which may render a radiological classification of Bosniak III or IV. FDG PET/CT is helpful in the detection of metastases. TCRC has definitive malignant potential. Our findings support a possible relationship to PRCC. The tyrosine kinase inhibitor sunitinib may be used a therapeutical agent with partial response and temporary effect.

Antegrade mini-invasive nephroureterectomy: laparoscopic nephrectomy, transurethral excision of ureterovesical junction and lower abdominal incision.

INTRODUCTION: We describe another variant of nephroureterectomy - antegrade mini-invasive nephroureterectomy (AMNUE). METHODS: AMNUE starts with a laparoscopic nephrectomy in the flank position. The specimen is enclosed in a bag without dividing the ureter, and the patient is positioned to the lithotomy position. Then the ureterovesical junction is excised transurethrally with a Collins knife. Finally, the specimen is removed and the ureter is plucked out through a short lower abdomen incision. PATIENTS: From March 2005 to November 2008, 35 patients underwent nephroureterectomy: 7 as an open procedure, 8 as a laparoscopic nephrectomy with open ureterectomy, 8 as a complete laparoscopic nephroureterectomy, and 12 were admitted into the AMNUE group (7 men and 5 women, mean age 71 +/- 7 years, range 54-81 years). RESULTS: Tumors were found 6 times on both sides. The mean operation time was 165 +/- 32 min (105-210 min), and the mean blood loss was 150 +/- 91 ml (50-400 ml). Histology revealed 11 urothelial cancers and 1 papillary renal cell carcinoma. There was only 1 hematoma of the abdominal wall. CONCLUSION: AMNUE is a fast, safe and easily reproducible technique. It eliminates the risk of spillage of tumorous cells into the urine, which is possible in techniques where the ureter is excised with a Collins knife as the first procedure. The disadvantages of this approach are the necessary repositioning of the patient and that the long-term oncological results are currently unknown. AMNUE can be used when a complete laparoscopic nephroureterectomy is not technically feasible due to problems in the pelvis.

A distinctive translocation carcinoma of the kidney ["rosette-like forming," t(6;11), HMB45-positive renal tumor].

OBJECTIVE: Recently, a novel renal carcinoma with specific clinical and histological characteristics and translocation t(6;11)(p21.1;q12 or q13) has been identified. We have found 11 cases in the literature, and we are adding another 3 cases. MATERIALS AND METHODS: Three cases were found in the Plzen pathological register with approximately 15,000 cases of kidney tumors. There were two females and 1 male, aged 22, 24, and 39 years. RESULTS: The sizes of the tumors were 40, 136, and 10 mm. Two tumors were found incidentally; the biggest one was self-palpated by a 24-year-old pregnant patient. Patients are without any signs of disease 42, 20, and 17 months after surgery. CONCLUSION: This tumor is a distinctive and rare translocation carcinoma of the kidney [t(6;11), HMB45 positive]. All cases with known clinical data arose in younger people. The malignant potential is probably low.

GreenLight (532 nm) laser partial nephrectomy followed by suturing of collecting system without renal hilar clamping in porcine model.

OBJECTIVES: To assess the feasibility of partial nephrectomy (PN) without renal hilar clamping using the 80-W GreenLight (532 nm) laser with opening of the collecting system followed by its suture in a porcine model. METHODS: We performed 12 open laser PNs in 6 farm pigs. We used the technique of incisional laser ablation of the lower pole of the right kidney. The pigs were kept alive, and 2 weeks later, underwent the same technique on the left kidney, followed by immediate killing. We recorded the acute and chronic outcomes. Renal parenchyma resection was achieved solely with the laser. The collecting system was opened with the laser in each procedure. All renal specimens underwent retrograde pyelography and histologic examination. RESULTS: All procedures were completed without renal hilar clamping. The mean operative and laser time was 67.1 +/- 20.6 minutes (range 35-95) and 17.8 +/- 6.4 minutes (range 10-30), respectively. The mean resected kidney mass was 17% +/- 0.5% (range 10%-27%) of the total kidney mass. The mean blood loss was 142.5 +/- 88.9 mL (range 50-350). No evidence of urinary extravasation was seen after the acute procedures, but proven urinomas with decayed suture were found after all chronic procedures. CONCLUSIONS: PN using the GreenLight laser is a feasible method for renal parenchyma incisional ablation. The laser hemostatic effect of interlobar vessel bleeding is safe and sufficient. The sutured collecting system after laser PN cannot heal in the thermically damaged tissue. The method is applicable to peripherally located lesions, without entering the collecting system. More prospective animal studies are necessary before application in humans.