Segmental 3D Image-Guided Robot-Assisted Partial Nephrectomy (3D-IGRAPN) in Selected Cases of Localized Renal Urothelial Carcinoma

Segmental 3D Image-Guided Robot-Assisted Partial Nephrectomy (3D-IGRAPN) in Selected Cases of Localized Renal Urothelial Carcinoma | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Segmental 3D Image-Guided Robot-Assisted Partial Nephrectomy (3D-IGRAPN) in Selected Cases of Localized Renal Urothelial Carcinoma Abderrahmane Khaddad, Gaëlle Margue, Xavier Lacroix, Pierre Dubus, and 10 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7878861/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 04 Dec, 2025 Read the published version in World Journal of Urology → Version 1 posted 8 You are reading this latest preprint version Abstract Radical nephroureterectomy is the standard treatment for renal upper urinary tract urothelial cancer, but may expose patients to renal failure and hemodialysis. We aimed to evaluate the outcomes of nephron-sparring surgery in three selected cases of localized renal UUTUC confined to a single calyx treated by segmental 3D image-guided robot assisted partial nephrectomy. All tumors were non-invasive and confined to either the superior or inferior calyx, refractory to endoscopic treatment and without evidence of synchronous lesions, lymph nodes involvement, or metastasis. All procedures were performed using the Da Vinci Xi robot, with preoperative planning and intraoperative guidance based on a 3D-model reconstructed from CT-urography. Key surgical principles included selective devascularization, avoidance of main artery clamping, and no opening of the concerned excretory tract. Mean patient age was 58 years, estimated blood loss was 166 mL and mean operative time was 272 minutes. All patients were discharged on postoperative day 1, with no perioperative complications. On patient experienced recurrences treated successfully by ureteroscopy. At 23,3 months of median follow-up, all patients were disease-free. Although limited to three patients, this initial experience suggests the potential value of this technique. However, larger studies with long-term follow-up are warranted to confirm its safety and efficacy. Figures Figure 1 Figure 2 Figure 3 Figure 4 Introduction Upper urinary tract urothelial cancer (UUTUC) accounts for 5–10% of urothelial carcinomas, with an incidence of 1–2/100 000 per year (1). Around 60% are kidney-located (2). The standard treatment for localized renal UUTUC is radical nephroureterectomy (RNU) with bladder cuff excision (BCE), although endoscopic treatment may be considered for selected patients (3). When endoscopic treatment fails or is impossible, the only remaining conservative technique which spare nephrons is partial nephrectomy, which may be considered if the tumor is focally located in a limited part of the kidney. Conservative approach is typically reserved for low-grade, non-invasive, and completely resectable tumors on imaging. Patients must be informed of the risk of recurrence and remain compliant with close surveillance, including imaging and ureteroscopy (URS) (4). Conservative treatment may also be considered in cases with larger and more aggressive tumors, with imperative indications, such as bilateral disease, solitary kidney or chronic kidney disease (5). Indeed, end-stage renal failure resulting from renal malignancy is associated with a limited survival (6). Two series have previously reported outcomes of open partial nephrectomy for localized renal UUTUC (7,8). Recent advances in robotic surgery, imaging and 3D reconstruction have allowed for increasingly precise nephron-sparing procedures and improved functional outcomes (9). These innovations are particularly valuable in anatomically favorable cases of renal UUTUC confined to a single calix, where endoscopic treatment is not achievable. We have incorporated these tools – alongside intraoperative ultrasound – to perform a highly selective, anatomy-based segmental resection. Key principles of this segmental approach include selective devascularization, no renal artery clamping, early exclusion of the concerned caliceal stem and avoid opening the excretory tract to prevent tumor spillage. We report a prospective series of three consecutive patients who underwent a segmental 3D-IGRAPN for localized renal UUTUC. We aimed to describe the feasibility and assess the safety and early oncologic outcomes of this surgical approach. Methods Clinical cases Three patients with localized UUTUC were treated with 3D-IGRAPN. Ureteroscopy with biopsy confirmed urothelial carcinoma. All surgical indications were discussed and approved in multidisciplinary meeting. Staging included chest-abdomen-pelvis CT. Inclusion criteria were unifocal urothelial carcinoma confined to upper/lower calyx, no other upper urinary tract tumor, no lymph node/distant metastases, and chronic renal failure or high risk of recurrence due to Lynch syndrom. Patients were selected for compliance with long-term follow-up and informed about recurrence risk and requirement of close follow-up. All provided written consent, and the study was approved by the local ethic committee. Pre-operative planning Endoscopic evaluation by fURS was mandatory, for tumor biopsy, and confirmation of single calyx involvement, allowing further surgical exclusion in safe oncological margin. A multiphase CT-urography with 0.6mm slices (Fig. 1 ) allowed semi-automatic 3D reconstruction using Synapse 3D. The virtual segmented model, manipulable in real time (Fig. 2 ) provided detailed vascular and urinary anatomy for surgical planning, particularly the dissection of the tumoral calyceal stem and selective devascularization. Surgical procedure (10) All procedures were performed using the Da Vinci Xi robotic system (Intuitive Surgical Inc., Sunnyvale, CA, USA) by an experienced surgeon (J-C.B.) (> 2,200 robotic renal surgeries). The 3D model and intraoperative ultrasound (US) were displayed via the Tile Pro for real-time guidance. The aim was to achieve segmental partial nephrectomy based on urinary tract anatomy. After full mobilization of the kidney, the segmental approach consisted first of defining the segment of parenchyma drained by the caliceal stem containing the tumor. Secondly, the arterial branches supplying the relevant parenchymal segment are selected, which will also allow to preserve the arterial branches supplying the remaining parenchyma. Finally, the venous branches were also identified. Extensive dissection of arterial, venous, and urinary structures was carried out. The tumoral calyceal stem was isolated and ligated first to minimize the risk of tumor seeding (Fig. 3 , image d). IUS was also used to precisely localize the affected calyx and guide the parenchyma transection, avoiding inadvertent opening of the excretory tract. Selective devascularization of the tumoral segment was performed by ligating and transecting the arterial and venous branches supplying the affected portion of the kidney (Fig. 3 , images a-c). All three surgeries were performed off-clamp, allowed by preliminary segmental anatomic devascularization and the extent of parenchymal induced ischemia was confirmed by fluorescence. Parenchymal hemostasis was achieved using monopolar coagulation and a running V-loc™ suture. Integrity of the remaining collecting system was tested with intra-operative pelvis instillation of saline, and leaks were closed with a slow-resorbing monofilament suture. At the end of the procedure, fluorescence confirmed adequate perfusion of the remaining kidney (Fig. 3 , images e-f). Results Patient characteristics are summarized (Table 1). Mean age was 58 years. All patients were in good general condition (ECOG 0) with no major comorbidities. Two had Lynch syndrome; one patient had a stage III chronic kidney disease. Preoperative endoscopic evaluation revealed a tumor confined in the upper calyx (2 cases) or the inferior calyx with a bifid ureter and upper tract system (1 case). Endoscopic treatment was unsuccessful in the three cases due to high-burden tumor. Biopsies demonstrated low grade pTa tumors (2 patients) and a high-grade pTa tumor (1 patient). In situ urinary cytopathology were negative for High-Grade Urothelial Carcinoma in all patients. CT-urography excluded any signs of renal parenchymal or perirenal fat invasion (cT3), or lymph node invasion. Mean operative time was 272 min (235–345) and estimated blood loss was 166 ml (100–250). No intraoperative complication or conversion occurred. All patients were discharged on postoperative day 1. Final pathology revealed low-grade pTa (1 patient) and high-grade pT1 (2 patients) (Fig. 4), all R0. Oncological follow-up included CT scan, cytology and fURS at 3 and 6 months, then every 4–6 months. All remaining calyces were accessible with flexible URS. Systematic flexible URS were stopped after 1 year without kidney or ureteric disease and surveillance was pursued using CT scan, urine cytopathology and bladder cystoscopy. Median follow-up was 23,3 months (36–12). Patient 1 showed 2 recurrencies during follow up (pTa low grade pelvic and pTa high grade ureteral) both treated by flexible ureteroscopy at 6 months and 15 months. Patients 2 and 3 showed no recurrencies during follow up. Discussion We report here the first series of patients treated with 3D-IGRAPN for localized renal UUTUC. At a mean follow-up of 23,3 months, all three patients remained free of disease, and none developed end-stage renal disease (ESRD). However, this study has major limitations. It is a retrospective study with a very limited number of patients. This procedure was considered here for patients with a chronic kidney failure or a high risk of recurrence due to a Lynch syndrome, after failure of prior endoscopic treatment. Then, CT-urography and fURS with tumor biopsy were required for patient selection. Eligible patients had a unifocal urothelial carcinoma confined to either the upper or lower calyx, with no other tumor in the upper urinary tract, and no evidence of lymph node or distant metastases. All our three patients showed no suspicion of parenchyma or fat tissue invasion which correspond to a pT3 tumor. This should be weighed against the imperfect sensitivity of CT-urography in detecting pT3 tumors (11). Uro-MRI was not used here, although this imaging modality is an alternative in cases of renal contraindication to CT scan. Even though further progress is expected, it currently remains inferior for the detection and TNM classification of UUTUC (12). Several key surgical principles were respected throughout the procedure. Unlike standard partial nephrectomy, this approach relied on urinary tract segmentation to plan a segmental resection tailored to tumor location. A “segmental” partial nephrectomy was performed with initial ligation of the involved calyx, followed by parenchymal sectioning without opening the collecting system. We demonstrated here the feasibility of this procedure, when supported by preoperative planning (CT scan and fURS) and intraoperative guidance tools, in particular 3D model, but also IUS and indocyanine green. Preoperative 3D anatomical model was critical for preoperative planning and intraoperative guidance, particularly for selective devascularization and precise dissection of the renal pelvis and collecting system (Fig. 3 ). The role of CT-scan based 3D reconstruction in improving outcomes in robot-assisted partial nephrectomy has been previously demonstrated in the context of renal tumors (13). IUS allowed for accurate localization of the affected calyx and guided parenchymal transection, helping to avoid unintended opening of the collecting system. Indocyanine green was also a valuable adjunct, aiding both in selective devascularization and in confirming adequate perfusion of the remaining parenchyma. Our perioperative results – absence of complications, minimal blood loss, and short hospital stay – can be attributed to careful preoperative planning, real-time 3D guidance, and the minimally invasive robotic approach. These outcomes are consistent with those reported in other 3D-IGRAPN series for renal tumors (9). Our functional results are promising, with a a mean eGFR reduction of – 10,4%, and no patient developed end-stage renal failure. These results, similar to 3D-IGRAPN for kidney cancer (9), can also theoretically be explained by the poor prior function of the tumoral kidney segment, the absence of peroperative artery clamping, and the preservation of the vascularization of the remaining kidney. Nevertheless, none of the treated patients had preoperative severe renal failure or were single kidney, and data on these patients is crucial. In oncological terms, the technique appears to be safe but does not eliminate the need for close endoscopic monitoring. One patient experienced a recurrence in the renal pelvis and in the lumbar ureter. This underscores the importance of rigorous surveillance, not only by CT-urography and cytopathologies but also ureteroscopies. Notably, no progression occurred, and the recurrences – an infracentimetric pTa lesions – was successfully treated endoscopically. Our close monitoring protocol, which includes regular fURS at least during the first year, in addition to CT-urography, cystoscopy, and cytology, seemed appropriate to us given the significant theoretical risk of recurrence. Compared to the second-look ureteroscopy at 6 weeks recommended after endoscopic laser treatment (4), the first ureteroscopy at 3 months seemed appropriate to us due to remaining kidney recovery renal and to the complete tumor resection with negative margins in pathology. At least for now, it doesn't seem reasonable to avoid ureteroscopy during monitoring, given how imaging methods (CT-urography an uro-MRI) resolution isn't sharp enough to catch recurrences early on (12). Importantly, all those results reflect the experience of a high-volume center and a surgeon with substantial expertise in renal robotic renal surgery, working on development and assessment of innovative tools to improve the results of these complex surgeries (14). This level of technical proficiency is essential for undertaking such rare and complex procedures. To date, only two prior series – comprising a total of 20 patients – have reported outcomes of partial nephrectomies for UUTUC, and all were performed via open surgery in patients with imperative indications (7,8). Goel et al. (7) reported outcomes about 12 partial nephrectomies for renal UUTUC between 1990 and 2001. All patients were in imperative indication and 10 (83%) of them had a solitary kidney. Partial nephrectomy was performed through a flank incision, with or without cold ischemia, and with IUS if required. At a mean follow-up of 57,7 months, 2 patients (16,7%) required hemodialysis and they observe progression with metastasis in 6 patients (50%). However, this high progression rate should be contrasted with the pT3 and positive surgical margins rates, both 50%. Macari et al. (8) reported 8 cases of open partial nephrectomies between 1997 and 2001 for patients with renal UUTUC and imperative indication of nephron-sparring surgery. Seven patients (87,5%) experienced postoperative complications, and mean hospitalization duration was 7 days. pT stage were pT2 or lower for all patients and all patients had negative surgical findings. During follow-up, 5 (63,5%) patients presented with recurrencies of which 4 were successfully treated endoscopically, and one patient showed a progression with metastasis. 2 patients (27%) developed end-stage renal failure and required hemodialysis. Finally, It appears that this procedure may be offered to patients with indication of nephron-sparring surgery, affected by kidney UUTUC confined in a calyx, with careful preoperative planning including flexible ureteroscopy and a CT scan. Indeed, with the evolution of more and more conservative practices, this procedure may be used in cases where endoscopic treatment has failed, as segmental ureterectomy is recommended in low ureter high-risk UUTUC (4). In patients with a ≥ cT3 tumor, this procedure appears to be risky from an oncological viewpoint but may be discussed in cases with very high risk of postoperative hemodialysis if the preoperative evaluation seems to predict a complete surgery with negative surgical margins. High resolution CT-urography with 3D-reconstructions is a helpful tool to optimally prepare these complex surgeries. Obviously, this procedure implies robotic mini-invasive surgery, and to be performed in a center with expertise in renal surgery. Much more data will be needed to fully validate this procedure and specify its indications. Future randomized prospectives studies – such as the ongoing ACCURATE trial, which compare outcomes between 3D-IGRAPN and standard RAPN for complex kidney tumors (15) – will help determine the added value of 3D guidance in nephron-sparing surgery. Additionally, augmented reality (AR) technologies, integrating 3D overlays onto the surgical field are under development and could significantly enhance anatomical precision during these procedures (16)(17). AR appears especially promising for highly segmental, anatomy-driven surgeries such as the one described here. Conclusion The integration of robotic surgery with advanced planning tools such as 3D reconstruction paves the way for more precise and personalized approaches in renal surgery. Nephron-sparring surgery in selected cases of localized UUTUC is an interesting feature of those personalized approaches. Although limited by the small sample size and short follow-up, this initial experience suggests that segmental 3D-IGRAPN can be a safe and effective option for selected cases of localized, non-invasive renal UUTUC refractory to endoscopic treatment. Long-term endoscopic and radiologic surveillance remains mandatory after such a conservative management. Declarations Competing Interests J-C.B. is a proctor for Intuitive Surgical. Author Contribution A.K. and J-C.B. worked on project development, methodology and data analysis. A.K., C.K. and J-C.B. wrote the main manuscript text. A.K. and C.K. prepared figures and tables. A.K., X.L. and G.M. participated on investigation and data collection. All authors supervised the research and reviewed the manuscript. References Siegel RL, Miller KD, Fuchs HE, Jemal A. Cancer statistics, 2022. CA Cancer J Clin. janv 2022;72(1):7‑33. Almås B, Halvorsen OJ, Johannesen TB, Beisland C. 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Additional Declarations Competing interest reported. J-C.B. is a proctor for Intuitive Surgical. Supplementary Files Table1.docx Cite Share Download PDF Status: Published Journal Publication published 04 Dec, 2025 Read the published version in World Journal of Urology → Version 1 posted Editorial decision: Revision requested 02 Nov, 2025 Reviews received at journal 26 Oct, 2025 Reviewers agreed at journal 24 Oct, 2025 Reviewers agreed at journal 23 Oct, 2025 Reviewers invited by journal 23 Oct, 2025 Editor assigned by journal 17 Oct, 2025 Submission checks completed at journal 17 Oct, 2025 First submitted to journal 16 Oct, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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01:29:01","extension":"html","order_by":14,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":54459,"visible":true,"origin":"","legend":"","description":"","filename":"earlyproof.html","url":"https://assets-eu.researchsquare.com/files/rs-7878861/v1/4a2aa0c5f03e8a8b6a2c272b.html"},{"id":95065633,"identity":"a181b1c0-1fd1-413a-a28f-7605f2bbe975","added_by":"auto","created_at":"2025-11-04 01:29:01","extension":"jpeg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":685087,"visible":true,"origin":"","legend":"\u003cp\u003ePreoperative CT-urography showing tumor, in case 1 (a and b), case 2 (c and d) and case 3 (e and f)\u003c/p\u003e","description":"","filename":"image1.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-7878861/v1/67bb77071f8441b97500a284.jpeg"},{"id":95222925,"identity":"daa4ba87-194e-4d60-85d2-2121a9cd7c40","added_by":"auto","created_at":"2025-11-05 16:21:21","extension":"jpeg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":321861,"visible":true,"origin":"","legend":"\u003cp\u003e3D reconstructions of tumoral kidneys based on preoperative CT-scan (n=3), case 1 (image a), case 2 (image b), and case 3 (image c)\u003c/p\u003e","description":"","filename":"image2.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-7878861/v1/8f303328ed51574f74d737f9.jpeg"},{"id":95065623,"identity":"0efb2830-7d50-45b9-93e1-b1332f3ca90b","added_by":"auto","created_at":"2025-11-04 01:29:00","extension":"jpeg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":491949,"visible":true,"origin":"","legend":"\u003cp\u003ePeroperative images of case 1: selective arterial and venous devascularization (a–c), exclusion of the tumoral calyx stem (d), and ICG perfusion assessment before (e) and after resection (f)\u003c/p\u003e","description":"","filename":"image3.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-7878861/v1/890e7ed895a0b990c4d2bf6b.jpeg"},{"id":95065624,"identity":"6b82b6c7-2d92-42fd-b967-d35e3f0d185a","added_by":"auto","created_at":"2025-11-04 01:29:01","extension":"jpeg","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":609253,"visible":true,"origin":"","legend":"\u003cp\u003eMacroscopic view of the surgical specimen confirming tumor involvement of the caliceal stem, image a for case 1, b for case 2 and c for case 3 (n=3)\u003c/p\u003e","description":"","filename":"image4.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-7878861/v1/188a91440f059b577bd8085c.jpeg"},{"id":97723771,"identity":"211b4738-4aff-442d-99af-4cdf947843b8","added_by":"auto","created_at":"2025-12-08 16:05:35","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2529521,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7878861/v1/e814f157-289b-434f-8b07-022182200fce.pdf"},{"id":95065626,"identity":"767e8c47-f766-42f4-9709-7e73fa75fed2","added_by":"auto","created_at":"2025-11-04 01:29:01","extension":"docx","order_by":0,"title":"","display":"","copyAsset":false,"role":"supplement","size":17270,"visible":true,"origin":"","legend":"","description":"","filename":"Table1.docx","url":"https://assets-eu.researchsquare.com/files/rs-7878861/v1/d5f70ff7d5339038994f9df3.docx"}],"financialInterests":"Competing interest reported. J-C.B. is a proctor for Intuitive Surgical.","formattedTitle":"Segmental 3D Image-Guided Robot-Assisted Partial Nephrectomy (3D-IGRAPN) in Selected Cases of Localized Renal Urothelial Carcinoma","fulltext":[{"header":"Introduction","content":"\u003cp\u003eUpper urinary tract urothelial cancer (UUTUC) accounts for 5\u0026ndash;10% of urothelial carcinomas, with an incidence of 1\u0026ndash;2/100 000 per year (1). Around 60% are kidney-located (2). The standard treatment for localized renal UUTUC is radical nephroureterectomy (RNU) with bladder cuff excision (BCE), although endoscopic treatment may be considered for selected patients (3). When endoscopic treatment fails or is impossible, the only remaining conservative technique which spare nephrons is partial nephrectomy, which may be considered if the tumor is focally located in a limited part of the kidney. Conservative approach is typically reserved for low-grade, non-invasive, and completely resectable tumors on imaging. Patients must be informed of the risk of recurrence and remain compliant with close surveillance, including imaging and ureteroscopy (URS) (4). Conservative treatment may also be considered in cases with larger and more aggressive tumors, with imperative indications, such as bilateral disease, solitary kidney or chronic kidney disease (5). Indeed, end-stage renal failure resulting from renal malignancy is associated with a limited survival (6). Two series have previously reported outcomes of open partial nephrectomy for localized renal UUTUC (7,8).\u003c/p\u003e\u003cp\u003eRecent advances in robotic surgery, imaging and 3D reconstruction have allowed for increasingly precise nephron-sparing procedures and improved functional outcomes (9). These innovations are particularly valuable in anatomically favorable cases of renal UUTUC confined to a single calix, where endoscopic treatment is not achievable. We have incorporated these tools \u0026ndash; alongside intraoperative ultrasound \u0026ndash; to perform a highly selective, anatomy-based segmental resection. Key principles of this segmental approach include selective devascularization, no renal artery clamping, early exclusion of the concerned caliceal stem and avoid opening the excretory tract to prevent tumor spillage.\u003c/p\u003e\u003cp\u003eWe report a prospective series of three consecutive patients who underwent a segmental 3D-IGRAPN for localized renal UUTUC. We aimed to describe the feasibility and assess the safety and early oncologic outcomes of this surgical approach.\u003c/p\u003e"},{"header":"Methods","content":"\u003cp\u003eClinical cases\u003c/p\u003e\u003cp\u003eThree patients with localized UUTUC were treated with 3D-IGRAPN. Ureteroscopy with biopsy confirmed urothelial carcinoma. All surgical indications were discussed and approved in multidisciplinary meeting. Staging included chest-abdomen-pelvis CT.\u003c/p\u003e\u003cp\u003eInclusion criteria were unifocal urothelial carcinoma confined to upper/lower calyx, no other upper urinary tract tumor, no lymph node/distant metastases, and chronic renal failure or high risk of recurrence due to Lynch syndrom. Patients were selected for compliance with long-term follow-up and informed about recurrence risk and requirement of close follow-up. All provided written consent, and the study was approved by the local ethic committee.\u003cdiv class=\"BlockQuote\"\u003e\u003cp\u003ePre-operative planning\u003c/p\u003e\u003cp\u003eEndoscopic evaluation by fURS was mandatory, for tumor biopsy, and confirmation of single calyx involvement, allowing further surgical exclusion in safe oncological margin.\u003c/p\u003e\u003cp\u003eA multiphase CT-urography with 0.6mm slices (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e1\u003c/span\u003e) allowed semi-automatic 3D reconstruction using Synapse 3D. The virtual segmented model, manipulable in real time (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e2\u003c/span\u003e) provided detailed vascular and urinary anatomy for surgical planning, particularly the dissection of the tumoral calyceal stem and selective devascularization.\u003cdiv class=\"BlockQuote\"\u003e\u003cp\u003eSurgical procedure (10)\u003c/p\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003eAll procedures were performed using the Da Vinci Xi robotic system (Intuitive Surgical Inc., Sunnyvale, CA, USA) by an experienced surgeon (J-C.B.) (\u0026gt;\u0026thinsp;2,200 robotic renal surgeries).\u003c/p\u003e\u003cp\u003eThe 3D model and intraoperative ultrasound (US) were displayed via the Tile Pro for real-time guidance. The aim was to achieve segmental partial nephrectomy based on urinary tract anatomy. After full mobilization of the kidney, the segmental approach consisted first of defining the segment of parenchyma drained by the caliceal stem containing the tumor. Secondly, the arterial branches supplying the relevant parenchymal segment are selected, which will also allow to preserve the arterial branches supplying the remaining parenchyma. Finally, the venous branches were also identified.\u003c/p\u003e\u003cp\u003eExtensive dissection of arterial, venous, and urinary structures was carried out. The tumoral calyceal stem was isolated and ligated first to minimize the risk of tumor seeding (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e3\u003c/span\u003e, image d). IUS was also used to precisely localize the affected calyx and guide the parenchyma transection, avoiding inadvertent opening of the excretory tract. Selective devascularization of the tumoral segment was performed by ligating and transecting the arterial and venous branches supplying the affected portion of the kidney (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e3\u003c/span\u003e, images a-c).\u003c/p\u003e\u003cp\u003eAll three surgeries were performed off-clamp, allowed by preliminary segmental anatomic devascularization and the extent of parenchymal induced ischemia was confirmed by fluorescence. Parenchymal hemostasis was achieved using monopolar coagulation and a running V-loc\u0026trade; suture. Integrity of the remaining collecting system was tested with intra-operative pelvis instillation of saline, and leaks were closed with a slow-resorbing monofilament suture. At the end of the procedure, fluorescence confirmed adequate perfusion of the remaining kidney (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e3\u003c/span\u003e, images e-f).\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003ePatient characteristics are summarized (Table\u0026nbsp;1). Mean age was 58 years. All patients were in good general condition (ECOG 0) with no major comorbidities. Two had Lynch syndrome; one patient had a stage III chronic kidney disease.\u003c/p\u003e\u003cp\u003ePreoperative endoscopic evaluation revealed a tumor confined in the upper calyx (2 cases) or the inferior calyx with a bifid ureter and upper tract system (1 case). Endoscopic treatment was unsuccessful in the three cases due to high-burden tumor. Biopsies demonstrated low grade pTa tumors (2 patients) and a high-grade pTa tumor (1 patient). In situ urinary cytopathology were negative for High-Grade Urothelial Carcinoma in all patients. CT-urography excluded any signs of renal parenchymal or perirenal fat invasion (cT3), or lymph node invasion.\u003c/p\u003e\u003cp\u003eMean operative time was 272 min (235\u0026ndash;345) and estimated blood loss was 166 ml (100\u0026ndash;250). No intraoperative complication or conversion occurred. All patients were discharged on postoperative day 1. Final pathology revealed low-grade pTa (1 patient) and high-grade pT1 (2 patients) (Fig.\u0026nbsp;4), all R0.\u003c/p\u003e\u003cp\u003eOncological follow-up included CT scan, cytology and fURS at 3 and 6 months, then every 4\u0026ndash;6 months. All remaining calyces were accessible with flexible URS. Systematic flexible URS were stopped after 1 year without kidney or ureteric disease and surveillance was pursued using CT scan, urine cytopathology and bladder cystoscopy. Median follow-up was 23,3 months (36\u0026ndash;12). Patient 1 showed 2 recurrencies during follow up (pTa low grade pelvic and pTa high grade ureteral) both treated by flexible ureteroscopy at 6 months and 15 months. Patients 2 and 3 showed no recurrencies during follow up.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eWe report here the first series of patients treated with 3D-IGRAPN for localized renal UUTUC. At a mean follow-up of 23,3 months, all three patients remained free of disease, and none developed end-stage renal disease (ESRD). However, this study has major limitations. It is a retrospective study with a very limited number of patients.\u003c/p\u003e\u003cp\u003eThis procedure was considered here for patients with a chronic kidney failure or a high risk of recurrence due to a Lynch syndrome, after failure of prior endoscopic treatment. Then, CT-urography and fURS with tumor biopsy were required for patient selection. Eligible patients had a unifocal urothelial carcinoma confined to either the upper or lower calyx, with no other tumor in the upper urinary tract, and no evidence of lymph node or distant metastases. All our three patients showed no suspicion of parenchyma or fat tissue invasion which correspond to a pT3 tumor. This should be weighed against the imperfect sensitivity of CT-urography in detecting pT3 tumors (11). Uro-MRI was not used here, although this imaging modality is an alternative in cases of renal contraindication to CT scan. Even though further progress is expected, it currently remains inferior for the detection and TNM classification of UUTUC (12).\u003c/p\u003e\u003cp\u003eSeveral key surgical principles were respected throughout the procedure. Unlike standard partial nephrectomy, this approach relied on urinary tract segmentation to plan a segmental resection tailored to tumor location. A \u0026ldquo;segmental\u0026rdquo; partial nephrectomy was performed with initial ligation of the involved calyx, followed by parenchymal sectioning without opening the collecting system. We demonstrated here the feasibility of this procedure, when supported by preoperative planning (CT scan and fURS) and intraoperative guidance tools, in particular 3D model, but also IUS and indocyanine green. Preoperative 3D anatomical model was critical for preoperative planning and intraoperative guidance, particularly for selective devascularization and precise dissection of the renal pelvis and collecting system (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e3\u003c/span\u003e). The role of CT-scan based 3D reconstruction in improving outcomes in robot-assisted partial nephrectomy has been previously demonstrated in the context of renal tumors (13). IUS allowed for accurate localization of the affected calyx and guided parenchymal transection, helping to avoid unintended opening of the collecting system. Indocyanine green was also a valuable adjunct, aiding both in selective devascularization and in confirming adequate perfusion of the remaining parenchyma. Our perioperative results \u0026ndash; absence of complications, minimal blood loss, and short hospital stay \u0026ndash; can be attributed to careful preoperative planning, real-time 3D guidance, and the minimally invasive robotic approach. These outcomes are consistent with those reported in other 3D-IGRAPN series for renal tumors (9).\u003c/p\u003e\u003cp\u003eOur functional results are promising, with a a mean eGFR reduction of \u0026ndash; 10,4%, and no patient developed end-stage renal failure. These results, similar to 3D-IGRAPN for kidney cancer (9), can also theoretically be explained by the poor prior function of the tumoral kidney segment, the absence of peroperative artery clamping, and the preservation of the vascularization of the remaining kidney. Nevertheless, none of the treated patients had preoperative severe renal failure or were single kidney, and data on these patients is crucial.\u003c/p\u003e\u003cp\u003eIn oncological terms, the technique appears to be safe but does not eliminate the need for close endoscopic monitoring. One patient experienced a recurrence in the renal pelvis and in the lumbar ureter. This underscores the importance of rigorous surveillance, not only by CT-urography and cytopathologies but also ureteroscopies. Notably, no progression occurred, and the recurrences \u0026ndash; an infracentimetric pTa lesions \u0026ndash; was successfully treated endoscopically. Our close monitoring protocol, which includes regular fURS at least during the first year, in addition to CT-urography, cystoscopy, and cytology, seemed appropriate to us given the significant theoretical risk of recurrence. Compared to the second-look ureteroscopy at 6 weeks recommended after endoscopic laser treatment (4), the first ureteroscopy at 3 months seemed appropriate to us due to remaining kidney recovery renal and to the complete tumor resection with negative margins in pathology. At least for now, it doesn't seem reasonable to avoid ureteroscopy during monitoring, given how imaging methods (CT-urography an uro-MRI) resolution isn't sharp enough to catch recurrences early on (12).\u003c/p\u003e\u003cp\u003eImportantly, all those results reflect the experience of a high-volume center and a surgeon with substantial expertise in renal robotic renal surgery, working on development and assessment of innovative tools to improve the results of these complex surgeries (14). This level of technical proficiency is essential for undertaking such rare and complex procedures.\u003c/p\u003e\u003cp\u003eTo date, only two prior series \u0026ndash; comprising a total of 20 patients \u0026ndash; have reported outcomes of partial nephrectomies for UUTUC, and all were performed via open surgery in patients with imperative indications (7,8). Goel et al. (7) reported outcomes about 12 partial nephrectomies for renal UUTUC between 1990 and 2001. All patients were in imperative indication and 10 (83%) of them had a solitary kidney. Partial nephrectomy was performed through a flank incision, with or without cold ischemia, and with IUS if required. At a mean follow-up of 57,7 months, 2 patients (16,7%) required hemodialysis and they observe progression with metastasis in 6 patients (50%). However, this high progression rate should be contrasted with the pT3 and positive surgical margins rates, both 50%. Macari et al. (8) reported 8 cases of open partial nephrectomies between 1997 and 2001 for patients with renal UUTUC and imperative indication of nephron-sparring surgery. Seven patients (87,5%) experienced postoperative complications, and mean hospitalization duration was 7 days. pT stage were pT2 or lower for all patients and all patients had negative surgical findings. During follow-up, 5 (63,5%) patients presented with recurrencies of which 4 were successfully treated endoscopically, and one patient showed a progression with metastasis. 2 patients (27%) developed end-stage renal failure and required hemodialysis.\u003c/p\u003e\u003cp\u003eFinally, It appears that this procedure may be offered to patients with indication of nephron-sparring surgery, affected by kidney UUTUC confined in a calyx, with careful preoperative planning including flexible ureteroscopy and a CT scan. Indeed, with the evolution of more and more conservative practices, this procedure may be used in cases where endoscopic treatment has failed, as segmental ureterectomy is recommended in low ureter high-risk UUTUC (4). In patients with a\u0026thinsp;\u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003e\u0026ge;\u003c/span\u003e\u0026thinsp;cT3 tumor, this procedure appears to be risky from an oncological viewpoint but may be discussed in cases with very high risk of postoperative hemodialysis if the preoperative evaluation seems to predict a complete surgery with negative surgical margins. High resolution CT-urography with 3D-reconstructions is a helpful tool to optimally prepare these complex surgeries. Obviously, this procedure implies robotic mini-invasive surgery, and to be performed in a center with expertise in renal surgery. Much more data will be needed to fully validate this procedure and specify its indications.\u003c/p\u003e\u003cp\u003eFuture randomized prospectives studies \u0026ndash; such as the ongoing ACCURATE trial, which compare outcomes between 3D-IGRAPN and standard RAPN for complex kidney tumors (15) \u0026ndash; will help determine the added value of 3D guidance in nephron-sparing surgery. Additionally, augmented reality (AR) technologies, integrating 3D overlays onto the surgical field are under development and could significantly enhance anatomical precision during these procedures (16)(17). AR appears especially promising for highly segmental, anatomy-driven surgeries such as the one described here.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eThe integration of robotic surgery with advanced planning tools such as 3D reconstruction paves the way for more precise and personalized approaches in renal surgery. Nephron-sparring surgery in selected cases of localized UUTUC is an interesting feature of those personalized approaches. Although limited by the small sample size and short follow-up, this initial experience suggests that segmental 3D-IGRAPN can be a safe and effective option for selected cases of localized, non-invasive renal UUTUC refractory to endoscopic treatment. Long-term endoscopic and radiologic surveillance remains mandatory after such a conservative management.\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch2\u003eCompeting Interests\u003c/h2\u003e\n\u003cp\u003eJ-C.B. is a proctor for Intuitive Surgical.\u003c/p\u003e\n\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\n\u003cp\u003eA.K. and J-C.B. worked on project development, methodology and data analysis. A.K., C.K. and J-C.B. wrote the main manuscript text. A.K. and C.K. prepared figures and tables. A.K., X.L. and G.M. participated on investigation and data collection. All authors supervised the research and reviewed the manuscript.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eSiegel RL, Miller KD, Fuchs HE, Jemal A. Cancer statistics, 2022. CA Cancer J Clin. janv 2022;72(1):7‑33. \u003c/li\u003e\n\u003cli\u003eAlm\u0026aring;s B, Halvorsen OJ, Johannesen TB, Beisland C. Higher than expected and significantly increasing incidence of upper tract urothelial carcinoma. A population based study. World J Urol. sept 2021;39(9):3385‑91. \u003c/li\u003e\n\u003cli\u003eRoumigui\u0026eacute; M, Seisen T, Masson-Lecomte A, Prost D, Allory Y, Xylinas E, et al. French AFU Cancer Committee Guidelines \u0026ndash; Update 2024\u0026ndash;2026: Upper urinary tract urothelial cancer (UTUC). Fr J Urol. nov 2024;34(12):102722. \u003c/li\u003e\n\u003cli\u003eRoupr\u0026ecirc;t M, Seisen T, Birtle AJ, Capoun O, Comp\u0026eacute;rat EM, Dominguez-Escrig JL, et al. European Association of Urology Guidelines on Upper Urinary Tract Urothelial Carcinoma: 2023 Update. Eur Urol. juill 2023;84(1):49‑64. \u003c/li\u003e\n\u003cli\u003eSaini S, Deveshwar SP, Hemal AK. Narrative review of nephron-sparing surgical management of upper tract urothelial carcinoma: is there a role for distal ureterectomy, segmental ureterectomy, and partial nephrectomy. Transl Androl Urol. janv 2024;13(1):156‑64. \u003c/li\u003e\n\u003cli\u003eNguyen KA, Vourganti S, Syed JS, Luciano R, Campbell SC, Shuch B. End-stage renal disease secondary to renal malignancy: Epidemiologic trends and survival outcomes. Urol Oncol. ao\u0026ucirc;t 2017;35(8):529.e1-529.e7. \u003c/li\u003e\n\u003cli\u003eGoel MC, Matin SF, Derweesh I, Levin H, Streem S, Novick AC. Partial nephrectomy for renal urothelial tumors: Clinical update. Urology. mars 2006;67(3):490‑5. \u003c/li\u003e\n\u003cli\u003eMacari D, Faerber GJ, Hafez KS, Hollenbeck BK, Montie JE, Wood DP, et al. Open surgical partial nephrectomy for upper tract urothelial carcinoma. Int J Urol. avr 2014;21(4):409‑12. \u003c/li\u003e\n\u003cli\u003eMichiels C, Khene ZE, Prudhomme T, Boulenger de Hauteclocque A, Cornelis FH, Percot M, et al. 3D-Image guided robotic-assisted partial nephrectomy: a multi-institutional propensity score-matched analysis (UroCCR study 51). World J Urol. f\u0026eacute;vr 2023;41(2):303‑13. \u003c/li\u003e\n\u003cli\u003eLacroix X, Khaddad A, Margue G, Alezra E, Estrade V, Capon G, et al. V07-11 IS ANATOMICAL 3D IMAGE-GUIDED ROBOTIC-ASSISTED PARTIAL NEPHRECTOMY (3D IGRAPN) A VIABLE TREATMENT OPTION FOR INTRARENAL UPPER TRACT UROTHELIAL CARCINOMA (UTUC)? J Urol [Internet]. mai 2025 [cit\u0026eacute; 31 ao\u0026ucirc;t 2025]; Disponible sur: https://www.auajournals.org/doi/10.1097/01.JU.0001109932.59301.39.11\u003c/li\u003e\n\u003cli\u003eJanisch F, Shariat SF, Baltzer P, Fajkovic H, Kimura S, Iwata T, et al. Diagnostic performance of multidetector computed tomographic (MDCTU) in upper tract urothelial carcinoma (UTUC): a systematic review and meta-analysis. World J Urol. mai 2020;38(5):1165‑75. \u003c/li\u003e\n\u003cli\u003eHonda Y, Nakamura Y, Teishima J, Goto K, Higaki T, Narita K, et al. Clinical staging of upper urinary tract urothelial carcinoma for T staging: Review and pictorial essay. Int J Urol. 2019;26(11):1024‑32. \u003c/li\u003e\n\u003cli\u003ePecoraro A, Amparore D, Checcucci E, Piramide F, Carbonaro B, De Cillis S, et al. Three-dimensional virtual models assistance predicts higher rates of \u0026laquo; successful \u0026raquo; minimally invasive partial nephrectomy: an Institutional analysis across the available trifecta definitions. World J Urol. avr 2023;41(4):1093‑100. \u003c/li\u003e\n\u003cli\u003ePitout A, Margue G, Rubat Baleuri F, Khaddad A, Pattou M, Bladou F, et al. Assessing Oncologic and Functional Outcomes of 3D Image-Guided Robotic-Assisted Partial Nephrectomy (3D-IGRAPN): A Prospective Study (UroCCR-186). Cancers. 25 juin 2025;17(13):2127. \u003c/li\u003e\n\u003cli\u003eMargue G, Bernhard JC, Giai J, Bouzit A, Ricard S, Jaffredo M, et al. Clinical Trial Protocol for ACCURATE: A CCafU-UroCCR Randomized Trial: Three-dimensional Image-guided Robot-assisted Partial Nephrectomy for Renal Complex Tumor (UroCCR 99). Eur Urol Oncol. 7 avr 2025;S2588-9311(25)00087-2. \u003c/li\u003e\n\u003cli\u003eKhaddad A, Bernhard JC, Margue G, Michiels C, Ricard S, Chandelon K, et al. A survey of augmented reality methods to guide minimally invasive partial nephrectomy. World J Urol. f\u0026eacute;vr 2023;41(2):335‑43. \u003c/li\u003e\n\u003cli\u003ePiana A, Amparore D, Sica M, Volpi G, Checcucci E, Piramide F, et al. Automatic 3D Augmented-Reality Robot-Assisted Partial Nephrectomy Using Machine Learning: Our Pioneer Experience. Cancers. 4 mars 2024;16(5):1047. \u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Tables","content":"\u003cp\u003eTable 1 is available in the Supplementary Files section.\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"world-journal-of-urology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"wjur","sideBox":"Learn more about [World Journal of Urology](https://link.springer.com/journal/345)","snPcode":"345","submissionUrl":"https://submission.nature.com/new-submission/345/3","title":"World Journal of Urology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-7878861/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7878861/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eRadical nephroureterectomy is the standard treatment for renal upper urinary tract urothelial cancer, but may expose patients to renal failure and hemodialysis. We aimed to evaluate the outcomes of nephron-sparring surgery in three selected cases of localized renal UUTUC confined to a single calyx treated by segmental 3D image-guided robot assisted partial nephrectomy. All tumors were non-invasive and confined to either the superior or inferior calyx, refractory to endoscopic treatment and without evidence of synchronous lesions, lymph nodes involvement, or metastasis. All procedures were performed using the Da Vinci Xi robot, with preoperative planning and intraoperative guidance based on a 3D-model reconstructed from CT-urography. Key surgical principles included selective devascularization, avoidance of main artery clamping, and no opening of the concerned excretory tract. Mean patient age was 58 years, estimated blood loss was 166 mL and mean operative time was 272 minutes. All patients were discharged on postoperative day 1, with no perioperative complications. On patient experienced recurrences treated successfully by ureteroscopy. At 23,3 months of median follow-up, all patients were disease-free. Although limited to three patients, this initial experience suggests the potential value of this technique. However, larger studies with long-term follow-up are warranted to confirm its safety and efficacy.\u003c/p\u003e","manuscriptTitle":"Segmental 3D Image-Guided Robot-Assisted Partial Nephrectomy (3D-IGRAPN) in Selected Cases of Localized Renal Urothelial Carcinoma","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-11-04 01:28:55","doi":"10.21203/rs.3.rs-7878861/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-11-02T19:02:05+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-10-26T11:34:34+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"306857870613731661078098863458090182917","date":"2025-10-24T20:19:29+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"218765540757928984649408964379974385760","date":"2025-10-23T17:13:37+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-10-23T09:57:45+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-10-17T16:53:04+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-10-17T13:02:04+00:00","index":"","fulltext":""},{"type":"submitted","content":"World Journal of Urology","date":"2025-10-16T14:33:06+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"world-journal-of-urology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"wjur","sideBox":"Learn more about [World Journal of Urology](https://link.springer.com/journal/345)","snPcode":"345","submissionUrl":"https://submission.nature.com/new-submission/345/3","title":"World Journal of Urology","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"03c439bb-bac2-4f26-90f1-f472a67d4a77","owner":[],"postedDate":"November 4th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-12-08T15:59:30+00:00","versionOfRecord":{"articleIdentity":"rs-7878861","link":"https://doi.org/10.1007/s00345-025-06099-x","journal":{"identity":"world-journal-of-urology","isVorOnly":false,"title":"World Journal of Urology"},"publishedOn":"2025-12-04 15:57:08","publishedOnDateReadable":"December 4th, 2025"},"versionCreatedAt":"2025-11-04 01:28:55","video":"","vorDoi":"10.1007/s00345-025-06099-x","vorDoiUrl":"https://doi.org/10.1007/s00345-025-06099-x","workflowStages":[]},"version":"v1","identity":"rs-7878861","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7878861","identity":"rs-7878861","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}