Ureteral stricture rate after endoscopic treatments for urolithiasis and related risk factors: systematic review and meta-analysis.

PURPOSE: We aimed to accurately determine ureteral stricture (US) rates following urolithiasis treatments and their related risk factors. METHODS: We conducted a systematic review and meta-analysis following the PRISMA guidelines using databases from inception to November 2023. Studies were deemed eligible for analysis if they included ≥ 18 years old patients with urinary lithiasis (Patients) who were subjected to endoscopic treatment (Intervention) with ureteroscopy (URS), percutaneous nephrolithotomy (PCNL), or shock wave lithotripsy (SWL) (Comparator) to assess the incidence of US (Outcome) in prospective and retrospective studies (Study design). RESULTS: A total of 43 studies were included. The pooled US rate was 1.3% post-SWL and 2.1% post-PCNL. The pooled rate of US post-URS was 1.9% but raised to 2.7% considering the last five years' studies and 4.9% if the stone was impacted. Moreover, the pooled US rate differed if follow-ups were under or over six months. Patients with proximal ureteral stone, preoperative hydronephrosis, intraoperative ureteral perforation, and impacted stones showed higher US risk post-endoscopic intervention with odds ratio of 1.6 (P = 0.05), 2.6 (P = 0.009), 7.1 (P < 0.001), and 7.47 (P = 0.003), respectively. CONCLUSIONS: The overall US rate ranges from 0.3 to 4.9%, with an increasing trend in the last few years. It is influenced by type of treatment, stone location and impaction, preoperative hydronephrosis and intraoperative perforation. Future standardized reporting and prospective and more extended follow-up studies might contribute to a better understanding of US risks related to calculi treatment.

Efficacy and safety of the EMS Swiss LithoClast® Trilogy for PCNL: results of the European multicentre prospective study on behalf of European Section of UroTechnology.

PURPOSE: PCNL requires a lithotrite to efficiently break stones, and some devices include active suction to remove the fragments. We set out to determine the efficacy and safety of the Swiss LithoClast® Trilogy, in a prospective European multicentre evaluation and compared it to published stone clearance rates for Trilogy based on surface area (68.9 mm2/min) and using the 3D calculated stone volume (526.7 mm3/min). METHODS: Ten European centres participated in this prospective non-randomized study of Trilogy for PCNL. Objective measures of stone clearance rate, device malfunction, complications and stone-free rates were assessed. Each surgeon subjectively evaluated ergonomic and device effectiveness, on a 1-10 scale (10 = extremely ergonomic/effective) and compared to their usual lithotrite on a 1-10 scale (10 = extremely effective). RESULTS: One hundred and fifty seven PCNLs using Trilogy were included (53% male, 47% female; mean age 55 years, range 13-84 years). Mean stone clearance rate was 65.55 mm2/min or 945 mm3/min based on calculated 3D volume. Stone-free rate on fluoroscopy screening at the end of the procedure was 83%. Feedback for suction effectiveness was 9.0 with 9.1 for combination and 9.0 for overall effectiveness compared to lithotrite used previously. Ergonomic score was 8.1, the least satisfactory element. Complications included 13 (8.2%) Clavien-Dindo Grade II and 2 (1.3%) Grade III. Probe breakage was seen in 9 (5.7%), none required using a different lithotrite. CONCLUSIONS: We have demonstrated that Trilogy is highly effective at stone removal. From a user perspective, the device was perceived by surgeons to be highly effective overall and compared to the most commonly used previous lithotrite, with an excellent safety profile.

Fluoroless Endourological Surgery for Stone Disease: a Review of the Literature-Tips and Tricks.

PURPOSE OF REVIEW: Urologists are at significant risk due to radiation exposure (RE) from endourological procedures for stone disease. Many techniques described have shown a reduction of RE. The purpose of this article is to review available protocols to decrease RE during such procedures and provide tips and tricks for their implementation. RECENT FINDINGS: Several low-radiation and radiation-free protocols for percutaneous nephrolithotomy and flexible ureteroscopy have been described as an attempt to reduce RE during surgery. Beginning with specific checklists to ensure adequate C-arm usage, fluoroless procedures are based on endoscopic assessment, tactile guidance, and use of ultrasound to avoid fluoroscopy. A specific preoperative checklist and low radiation or complete fluoroless radiation endourological procedures have shown to be effective, feasible, and safe. It is recommended for urologists to be aware of the risks of RE and apply the "ALARA" (As Low As Reasonably Achievable) protocols.

Does success in percutaneous nephrolithotomy depend only on stone size? Analysis of the predictive capacity for success and complications of the current nephrolithometry scoring systems and their relationship with the stone surface.

OBJECTIVE: To analyze the predictive capacity of the nephrolithometry scoring systems (GSS, STONE, CROES and S-ReSC) and stone surface regarding success and complications following percutaneous nephrolithotomy (PCNL). METHODS: We studied 392 patients who had undergone PCNL in our center. Only patients with a non-contrast CT (n = 240) were finally included for analysis. The predictive capacities for success and complications of the different scoring systems were evaluated using ROC curves and their area under the curve (AUC). RESULTS: Regarding success, the S-ReSC system had the highest predictive capacity with an AUC of 0.681 (95% CI 0.610-0.751), followed by the CROES with 0.667 (95% CI 0.595-0.738), the STONE with 0.654 (95% CI 0.579-0.728) and finally the GSS with 0.626 (95% CI 0.555-0.698). The stone surface as a single variable had an AUC of 0.641 (95% CI 0.565-0.718). As for complications, the S-ReSC had the highest AUC with 0.664 (95% CI 0.57-0.758), followed by STONE with 0.663 (95% CI 0.572-0.755), GSS with 0.626 (95% CI 0.555).-0.698) and CROES with 0.614 (95% CI 0.518-0.7). The stone surface alone had an AUC of 0.616 (95% CI 0.522-0.715). CONCLUSION: The nephrolithometry scales analyzed show a moderate predictive capacity for success and complications in patients undergoing PCNL in our center. Moreover, stone surface as an independent variable demonstrates moderate predictive capacity for both outcomes.

Technological innovations in shock wave lithotripsy.

INTRODUCTION: Since 1980, extracorporeal shock wave lithotripsy (SWL) has been employed in the treatment of urolithiasis, offering noninvasive alternatives to surgical techniques. In addition to being limited by the size and location of the stones, its efficacy is influenced by several factors. Despite the advancement of other surgical techniques, SWL could maintain its position with new improvements. Our objective is to review the existing literature on the latest advances in the extracorporeal treatment of lithiasis. MATERIAL AND METHODS: A non-systematic literature review was carried out from 2017 to 2023 to obtain 26 articles on three different emerging technologies in extracorporeal lithotripsy: Burst Wave Lithotripsy (BWL), Histotripsy, and Microbubble Lithotripsy (ML). RESULTS: The BWL uses sinusoidal bursts of US waves delivered at lower and higher frequencies than conventional SWL. Its mechanism of action generates a higher quality fragmentation (fine fragments) instead of generating tensile stresses for stone fracture resulting in larger fragments, as in traditional SWL. Studies in pigs and humans have shown effective fragmentation with a good safety profile. Based on High Intensity Focused Ultrasound (HIFU) technology, histotripsy fragments tissue through cavitation. Good in vitro results have been shown, but the formation of microbubbles between the stone and ultrasound waves hinders the progress of this technique. Microbubble Lithotripsy (ML) combines microbubbles and ultrasound for safe and effective stone fragmentation. In vitro and pig results are promising. This technique can help optimize treatments and reduce energy levels. CONCLUSIONS: Technological innovation is not only being applied to endourological techniques, but also to ESWL. New techniques such as BWL, histotripsy and ML are promising, with good results in the research phase.

Controversies in prostate cancer management: Consensus recommendations from experts in northern Spain.

In recent years, various aspects of prostate cancer (PC) management have undergone significant changes, including the implementation of therapeutic strategies such as the use of new hormonal agents like abiraterone, apalutamide, enzalutamide or darolutamide and the incorporation of next generation imaging techniques (NGI). However, the evidence regarding the role of NGI and the therapeutic decision-making based on their findings is not solid. Following the methodology of the Advanced Prostate Cancer Consensus Conference (APCCC), a multidisciplinary expert consensus was developed to address controversial questions concerning the use of NGI and clinical management in four priority scenarios: localized PC, PC after radical prostatectomy, PC after radiotherapy with curative intent, and metastatic hormone-sensitive PC. This consensus represents the opinions of medical oncology, radiation oncology and urology physicians and provides useful recommendations for clinical practice.

Initial results of endourological treatment of renoureteral lithiasis by means of flexible ureteroscopy and percutaneous surgery in an outpatient procedure in a tertiary care center.

OBJECTIVE: Urinary lithiasis is a prevalent disease with a high socioeconomic impact, where endourological surgery has shown excellent results with minimal complications. For its part, outpatient surgery is an efficient, safe and quality care model. We present our experience in the outpatient endourological treatment of lithiasis and a review of the main series. MATERIAL AND METHODS: Prospective analysis of 85 flexible or percutaneous procedures for the treatment of lithiasis, carried out in our center between January 2021 and April 2022. The main objective was to analyze the rate of unplanned admission and the success and incidence of complications as secondary objectives. The patients were selected following the inclusion criteria of the care process. RESULTS: The mean age was 56 ± 14 years. Urine culture was positive in 13.9% of the patients, 38% had a pre-surgical double-J catheter. Median stone surface was 55 mm 2 (961 ± 323 Hounsfield Units). 73 flexible and 12 percutaneous procedures were performed. 8 patients required immediate unplanned admission and another 2 during the first month. 94% were stone-free at the third month. No intraoperative complications were detected, although 16.5% of the patients presented some type of postoperative complication. CONCLUSION: In our experience, with a strict selection of patients and following a care process with multidisciplinary participation, endourological procedures are feasible and safe in the outpatient setting. Periodic monitoring of the results is essential for the sake of a constant improvement of the process.

A multidisciplinary consensus statement on the optimal pharmacological treatment for metastatic hormone-sensitive prostate cancer.

Androgen deprivation therapy (ADT) is the mainstay treatment for metastatic hormone-sensitive prostate cancer (mHSPC). The addition of docetaxel or new hormone therapies (abiraterone, apalutamide, or enzalutamide) improves overall survival and is currently the standard of care. However, the decision on the specific regimen to accompany ADT should be discussed with the patient, considering factors such as possible associated toxicities, duration of treatment, comorbidities, patient preferences, as there is no sufficient evidence to recommend one regimen over the other in most cases. This paper summarizes the evidence on the management of mHSPC and provides consensus recommendations on the optimal treatment in combination with ADT in mHSPC patients, with special attention to the patient's clinical profile.

Non-metastatic castration-resistant prostate cancer: management recommendations.

INTRODUCTION AND OBJECTIVE: Survival and quality of life (QoL) of patients with non-metastatic castration-resistant prostate cancer (nmCRPC) deteriorate significantly when they develop metastases. New generation antiandrogens (apalutamide, enzalutamide and darolutamide) can prolong metastasis-free survival (MFS) and overall survival (OS) in these patients, maintaining their QoL. MATERIAL AND METHODS: After the performance of a systematic review of the literature, a scientific committee reached a consensus on simple and practical recommendations to consolidate and improve the management of patients with nmCRPC in urology consultations. RESULTS: Recommendations are made on the frequency of PSA determination and imaging tests in patients with nmCRPC. The importance of co-morbidities in patients with nmCRPC is also highlighted, and recommendations are also made on functional and QoL assessment that can be carried out during urology consultations. The efficacy, safety, and effects on QoL of new generation antiandrogens are reviewed. CONCLUSIONS: To evaluate treatment of patients with nmCRPC, it is necessary to consider co-morbidities and QoL, in addition to age. New generation antiandrogens are a safe and effective treatment option for patients with nmCRPC. The recommendations of this review can be helpful in optimizing the management of nmCRPC patients in urology consultations.

Incidence of upper tract urothelial carcinoma in Spain. / Incidencia del carcinoma transicional del tracto urinario superior en España.

INTRODUCTION AND OBJECTIVES: The incidence of upper urinary tract tumors is currently unknown. The aim of this study is to determine the real incidence of upper tract urothelial carcinoma (UTUC) in Spain. MATERIAL AND METHODS: A descriptive, prospective and multicenter epidemiological study was conducted in 31 Spanish facilities by means of the Platform for Multicenter Studies of the Spanish Association of Urology. Recruitment was opened from May 1st, 2017 to April 30th, 2018. The original database was exported directly from the electronic Data Collection Logbook on December 15th, 2018, with a total of 404 cases registered (402 valid cases after depuration). Statistical analysis was performed using IBM SPSS software v 23 and EPIDAT v 3.4. RESULTS: The incidence adjusted to Spanish population from raw data was 3.27 cases per 100.000 inhabitants per year (2.93 - 3.61 95% CI) and 3,3 cases per 100.000 inhabitants per year (2.96-3.66 95%CI) when adjusted to European population by age. The mean age at diagnosis was 70 years, and 77% of patients were male. Thirty-four percent of patients had an incidental diagnosis. Tumors were most commonly located in the pyelocalyceal system (54%), followed by the distal ureter (22%). Prior ureteroscopy was performed in 114 patients: this technique modified the subsequent treatment indication in 58% of cases. Radical nephroureterectomy was performed in 311 patients. Kidney-sparing surgery was the elected treatment in 76 patients (20%). Complications were found in 69% of cases, most of them classified as Clavien 1 and 2 (86% of all complications). Postoperative mortality rate was 1.7%. CONCLUSIONS: UTUC adjusted incidence rate in Spain is 3.27 and 3.3 in Europe. Prior URS modified the treatment indication in 18% of patients. We found a 69% complication rate and a 1.7% mortality rate.

Current status of radiological protection in endourological procedures in Spain. / Estado actual de la protección radiológica en procedimientos endourológicos en España.

OBJECTIVE: To discover the extent of training in radiological protection (RP) of Spanish urologists who perform endourological procedures, and to analyse the use of on ionising radiation control and protection measures. MATERIAL AND METHODS: A survey conducted through the Plataforma de Investigación de Estudios Multicéntricos (PIEM) (Multicentre Study Research Platform) on the 1,894 associates of the Spanish Association of Urology, between April and October 2015. The questionnaire comprised 21 questions on endourological activity undertaken, RP training, and the use of protective measures, and personal dosimetry. Seventeen percent responded, and 238 surveys were eventually validated for study. RESULTS: Sixty-three percent of the respondents had received no type of RP training, 25% had first level accreditation, and only 12% second level. Fifty-seven percent, 27%, and 2% of the urologists used flap, wrist and crystalline dosimetry respectively. Use of radiation protection measures was insufficient. Fifty-three percent of the urologists at greatest risk of exposure had had no training in RP, 30% did not use flap dosimetry, and 40% used neither an apron or thyroid collar during the endourological procedures. CONCLUSIONS: RP training, dosis monitoring, and the use of ionising radiation protective measures are insufficient, even by practitioners most exposed to radiation. It is essential that these serious shortcomings in RP are corrected, at the level of the individual, in urology departments, scientific societies, and the health authorities.

Safety of percutaneous nephrolithotomy in patients on chronic anticoagulant or antiplatelet therapy.

In developed countries, the incidence of cardiovascular disease is increasing, therefore, anticoagulant and antiplatelet drugs are a widespread treatment nowadays. Percutaneous nephrolithotomy (PNL) is the first-line treatment for large or complex stones (> 2 cm) and remains an alternative for the smaller ones. The objective of this study is to analyze whether PNL surgery is a safe procedure in patients under a treatment discontinuation protocol for anticoagulant or antiplatelet therapies. We retrospectively studied 301 patients who underwent PNL in our hospital between 2008 and 2016 and identified 46 patients on chronic antiplatelet or anticoagulation treatment. With respect to PNL outcomes, the stone-free rate was similar (78 vs 74%, p = 0.762) in both groups, without any significant differences in the overall postoperative complications (17 vs 26%, p = 0.203). The incidence of hemorrhagic complications was similar between groups (12 vs 9%, p = 0.492), as demonstrated by the mean drop in hemoglobin (Hb), which was comparable in both cohorts (2.2 ± 1.3 vs 2.0 ± 1.4 p = 0.270) and the blood transfusion rate (14% in group A and 8% in group B, p = 0.205). No thromboembolic events were found within the year after the PNL procedure. PNL is a safe and effective intervention in patients under a treatment discontinuation protocol for anticoagulant or antiplatelet therapies. Although our study demonstrates the feasibility of this protocol, new scientific evidence aims to stratify the thromboembolic and bleeding risk of each patient to individualize the perioperative management thereafter.

[Gunshot bladder trauma: case report and literature review]. / Traumatismo vesical por arma de fuego: presentación de un caso y revisión de la literatura.

OBJECTIVE: To report one case of gunshot bladder trauma and to review its diagnosis and treatment in the related literature. METHODS: We report the case of a 43-year-old-male with an abdominal firearm wound and gross haematuria. Imaging diagnosis by abdominal and pelvic CT and CT-cystography. Surgical treatment. RESULTS: CT-cystography showed extraperitoneal bladder rupture. Exploratory laparotomy to evaluate for other associated injuries. Bladder wall surgical closure and ureteroneocystostomy with transvesical technique because of complete distal ureter tear. Broad spectrum antibiotherapy. Favourable progress. The patient was discharged at 14th day. CONCLUSIONS: Firearm bladder traumas are a rare entity. Surgical exploration and closure is mandatory. In haemodynamicaly stable patients, abdomen and pelvis CT and CT-cystography allow us to rule out associated injuries and to classify the bladder trauma type. Ureteral damage associated in 5-8,9%, diagnosed during surgical exploration. Broad-spectrum antibiotherapy in all patients.

[Complications of double j catheters and their endourological management]. / Complicaciones de los catéteres doble jota y su manejo endourológico.

The insertion of a double J catheter (DJ) has widespread, becoming a usual procedure and standard of care in urology. Despite its relative simplicity it is not free from intraoperative risks or problems during the weeks after the implant. Conversely, despite great advances in design of these catheters the ideal material has not been discovered yet, one that is perfectly biocompatible with urine and avoids completely the advent of complications. The range of problems associated with DJs is variable: from mild self-limited dysuria or hematuria to more complex situations with higher risk, such as catheter migration, complete calcification, breakage, obstruction and renal unit loss. The treatment of theses complications must combine maximal efficacy for their resolution with the least possible surgical aggression. Accordingly, the different options of endourological approach become very important and they are the cornerstone for the treatment of the complications associated with ureteral catheters. The objective of this review is to present the main complications derived from the insertion of a DJ, their diagnosis, prevention and treatment, focusing mainly in the different endourological techniques.

[Atypical sites of metastatic renal carcinoma. Literature review]. / Carcinoma renal metastásico de localización atípica. Revisión de la literatura.

OBJECTIVE: To review in the literature atypical sites of metastatic renal cell carcinoma, its onset, clinical features, diagnosis, treatment and prognosis. METHODS: To review, using Medline database, atypical sites of metastatic renal cell carcinoma in the last five years Spanish literature. RESULTS: There have been published 15 spanish articles about atypical metastatic renal cell carcinoma in the last five years. Most patients were male with a mean age of 62,3 years and methacronous metastases. Imaging and pathological diagnosis. Main sites: ocular, renal graft, larynx, suprarenal, brain, penis, gastric and pancreatic. Surgical treatment if the surgeon is able to remove the lesion. Inmunotherapy and radiotherapy in the rest of cases. CONCLUSIONS: Renal cell carcinoma represents about 3% of all adult malignancy neoplasms. Its metastatic sites, in order of frequency, are lung, bone and liver, whether synchronic or methacronic. Its location, clinical features, onset, evolution and prognosis is very variable. Individualized diagnostic and therapeutic approach, according to prognostic factors. The knowledge of this atypical sites in patients with renal cell carcinoma in the past can lead us to an earlier diagnosis and treatment which could change the evolution of the illness.

[Surgical complications after kidney transplantation. Research based on 185 cases]. / Complicaciones quirúrgicas post-trasplante renal. Estudio en 185 casos.

OBJECTIVE: To analyze the incidence of surgical complications its diagnosis and treatment after renal transplantation. METHODS: A retrospective study measuring the incidence of surgical complications and reviewing its diagnosis and treatment in 185 renal single transplants. RESULTS: 185 transplants, 27% had surgical complications. Only one patient lost the graft due to surgical complications and there was no associated mortality. Cold ischemia time 20 hours. Double J stenting in 19%, under surgeon's opinion. Vascular complications 3.2% (all of them renal artery stenosis). Urological complications 6.4%. Perinephric haematoma 7%. Lymphocele 4.9%. Peritoneum related complications 4%. Other 4%. The diagnosis was clinical and radiological in most of cases. 14% needed any kind of intervention. CONCLUSIONS: Our results are similar to those reported in other recent series. Only one surgical team involved and the same technique for vascular and vesico-ureteric anastomosis probably makes lower our complications rate. Early postoperative abdominal ultrasonography contributes to the diagnosis of surgical complications. The initial treatment approach is the endoscopic-conservative one, with exceptions.

Assessment of tissue damage due to percutaneous nephrolithotomy using serum concentrations of inflammatory mediators.

OBJECTIVES: To determine the percutaneous nephrolithotomy (PCNL) effects on the tissues using the quantification of inflammatory mediators, and to assess their impact on the development of postoperative complications. PATIENTS AND METHODS: Prospective observational non-randomized study on 40 patients underwent to PCNL. 50 patients with kidney stone who were treated by extracorporeal shock wave lithotripsy (ESWL) were used as control group. Interleukin-1beta (IL-1ß), tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6) and C-reactive protein (CRP) were determined at baseline (T0: before treatment), and at 2, 6 and 24hours after (T1, T2 and T3). RESULTS: No relevant changes on IL-1ß and TNF-α were found. IL-6 showed two peaks at 2 and 6hours post-PCNL (median 17.8 and 15.8 pg/mL, respectively). At 24hours CRP had reached its peak value (3.4mg/L). The group treated with ESWL no showed significant changes in any of the markers. The serum concentration of IL-6 and CRP at 24hours post-NLP is different depending on the occurrence of complications (P=.001 and P=.039, respectively). IL-6 showed a good predictive power for the development of complications (AUC .801). CONCLUSIONS: Tissue damage caused by the PCNL is low. This damage increases significantly in those cases showing postoperative complications. IL-6 at 24hours has been shown to be a good predictive tool for the development of complications.

Micropercutaneous nephrolithotomy. A new therapeutic option for pediatric renal lithiasis.

INTRODUCTION: Micropercutaneous nephrolithotomy is an evolution from the conventional percutaneous surgery in which pyelocaliceal access is obtained through minimum bore holes. Its objective is the complete removal of the calculi, lowering the morbidity associated with larger bore percutaneous tracts. MATERIAL AND METHODS: We present the case of a micropercutaneous nephrolithotomy performed in a 14-year-old female patient with a 35 mm diameter kidney stone located in the renal pelvis. Surgery was performed in the Galdakao-modified supine Valdivia position. Puncture was done under ultrasound and fluoroscopic guidance. The 4.85 Ch needle of the Microperc(®) set was used, completing the procedure through the 8 Ch working shaft. Lasertripsy was done with the Ho:YAG laser. An indwelling double J stent was placed at the end of the procedure. RESULTS: Operating time was 170 minutes. Hospital stay was one day. She suffered renal colic after 72 hours, which was resolved with oral analgesic treatment at home (Clavien I). She returned to school on the fifth postoperative day. The double J was removed at 2 weeks. At one month of the surgery, the patient is asymptomatic, a 4mm lower calyx residual stone being observed in the abdominal ultrasound. CONCLUSION: Micropercutaneous nephrolithotomy is a step forward towards the search for a less invasive kidney stone treatment. It is a safe and effective technique in the pediatric population, and it can be performed in the supine position, even in orthotropic kidneys. Future studies and collaborative works will help to better define its indications, to optimize its technique and to analyze its cost-effectiveness compared with other treatment options.

[Learning of percutaneous nephrolithotomy in supine position. An observational multicenter study]. / El aprendizaje de la nefrolitectomía percutánea en posición supina. Estudio observacional multicéntrico.

OBJECTIVE: To prospectively study the post-operative results and complications of percutaneous nephrolithotomy (PNL) in supine position to assess difficulty of learning it and how experience affects the results. To establish a relative comparison with the data published in the literature on the prone position. MATERIAL AND METHODS: A prospective observational multicenter study on PNL in Valdivia position or in its Galdakao variant was performed. Demographic variables and specific variables related to the lithiasis were collected. Technical aspects, surgery time, success rate and complications according to the Clavien-Dindo classifications were assessed. RESULTS: A total of 335 PNL in supine position conducted in 13 Spanish centers were registered from September 2008 to June 2011. The man:woman ratio was 1:1.28 and mean age 51.3+14.5 years. 211 (63%) cases were performed by urologists with experience in >50 cases and 124 (37%) by urologists with less experience. Mean operation time was 113.3 ± 46.4 min, 106.6 ± 38.2 for the experienced ones vs. 124.9 ± 56.2 in the novice ones (P<.002). No difference was detected in the mean size of the lithiasis. However, in the experienced group, there was a greater proportion of coraliform cases and multiple lithiasis than in the novice group (P<.001). Success rate evaluated as total absence of lithiasic residuals was 69.6%, without differences between groups (68.2 vs. 71.8%). In 102 (30.6%) patient had residual lithiasis and 60 (17,9%) required complementary treatment. Relative global success rate was 82.1% and complications rate 25.4%, without detecting differences between groups. However, the novel group had more major complications (P>.001). CONCLUSION: The PNL in supine position is obtaining rapid and consolidated diffusion in our setting and its effectiveness and safety seems to be equivalent to that described in the literature for PNL in prone position. It is possible to obtain good results with a modest learning curve. The rate of greater complications associated to the procedure decreases with experience.