Objective:To investigate the clinical application effect and preliminary experience of ureteroscopy-assisted flexible ureteroscopic lithotripsy in the treatment of transplanted kidney stones.Method:A retrospective analysis was conducted on the clinical data of 9 kidney transplant recipients with graft stones who underwent ureteroscopy-assisted flexible ureteroscopic lithotripsy at the First Affiliated Hospital of Zhengzhou University between January 2020 and January 2023. The recipients' general information, surgical procedures, and postoperative outcomes were reviewed and summarized. Additionally, a comprehensive literature search was performed in both Chinese and international databases, including CNKI, Wanfang, and the China Academic Journals Full-text Database, as well as PubMed and Web of Science. The search terms included " kidney transplant" "flexible ureteroscope" "ureteroscope" and " urinary tract stones" . The search covered all publications available up to December 2023.Result:The 9 recipients had a mean age of 37. 56 years (range: 27–54 years) . The onset time of the kidney stones ranged from 1 to 13 months after kidney transplantation. All recipients were diagnosed with transplanted kidney stones by CT and showed no symptoms of kidney colic at the time of onset. All transplanted kidneys were located in the right iliac fossa, with varying degrees of hydronephrosis. The smallest stone diameter was 0. 5 cm, and the largest was 1. 3 cm. The number of stones ranged from 1 to 3 per recipient; 6 cases had solitary stones, and 3 had multiple stones in the renal pelvis and calyces. In all 9 surgeries, the ureteral orifice of the transplanted kidney was located at the apex of the bladder using ureteroscopy, and a hydrophilic guidewire was inserted into the renal pelvis. A second ureteroscopy was then performed, guiding the ureteroscope tip into the transplanted ureteral orifice in coaxial alignment with the guidewire. A flexible ureteroscope sheath was advanced along the guidewire, followed by the insertion of a digital flexible ureteroscope to perform holmium laser dusting lithotripsy. Stone composition analysis revealed mixed calcium oxalate monohydrate and calcium oxalate dihydrate. The surgical duration ranged from 30 to 75 minutes. No complications such as massive bleeding, septic shock, or rejection occurred. Postoperative review at 1 month, after ureteral stent removal, showed no residual stones in any patient. During 6 months of follow-up, no recurrence of stones was observed, and the renal function of the transplanted kidneys remained stable compared to preoperative levels. A total of 19 related articles were identified through literature review, including 11 in English and 8 in Chinese. Chinese reports on transplanted kidney stones were all from single-center studies with small case numbers. In contrast, foreign meta-analyses and multicenter studies showed that treatments for transplanted kidney stones abroad mainly included antegrade/retrograde ureteroscopy and percutaneous nephroscopy.Conclusion:Ureteroscopy-assisted flexible ureteroscopic lithotripsy is a feasible treatment for transplanted kidney stones. It can effectively protect graft kidney function and has promising clinical application prospects.

Objective:To investigate the therapeutic outcomes of patients with horseshoe kidney and hydronephrosis under different surgical approaches and with or without isthmus division.Methods:This study is a retrospective case series research. A retrospective analysis was conducted on the clinical data of 23 patients with horseshoe kidney and hydronephrosis who underwent pyeloplasty at the Department of Urology, the First Affiliated Hospital of Zhengzhou University from January 2016 to December 2023. Among them, there were 11 males and 12 females, with an age of (33±15) years (range:7 to 64 years). Patients underwent preoperative examinations, including ultrasonography of the urinary system, intravenous urography, CT urography, or magnetic resonance urography. Retrograde urography or antegrade ureteropyelography was performed when necessary to clarify the degree of hydronephrosis, the location and length of ureteral stricture. For patients with severe hydronephrosis, a ureteral stricture segment >2 cm, a thick renal isthmus in horseshoe kidney, and markedly variant vasculature, open surgery or robotic surgery is preferred. For those with mild to moderate hydronephrosis, a ureteral stricture segment <2 cm, a thin renal isthmus in horseshoe kidney, and no significant vascular variations, laparoscopic surgery is the first choice. The decision to perform isthmectomy should be made based on a comprehensive intraoperative assessment, including the vascular supply to the isthmus, the degree of surrounding adhesions, and the thickness of the isthmus. Perioperative parameters and complications were recorded and analyzed, and regular follow-up was conducted for all patients.Results:All surgeries were successfully completed. Surgical approaches included open surgery in 4 cases, laparoscopic surgery in 14 cases, and robot-assisted laparoscopic surgery in 5 cases. The operative time for open surgery, laparoscopic surgery and robot-assisted laparoscopic surgery was (125±12) minutes (range: 112 to 141 minutes), (122±50) minutes (range: 60 to 233 minutes), and (130±36) minutes (range: 76 to 174 minutes), respectively. The blood loss ( M(IQR)) was 100 (25) ml (range: 50 to 100 mL) for open surgery, 35 (30) ml (range: 10 to 100 mL) for laparoscopic surgery, and 20 (10) ml (range: 20 to 50 ml) for robot-assisted laparoscopic surgery. Among 15 patients who underwent isthmus division with pyeloplasty (division group), the operation time was (138±42) minutes (range: 73 to 233 minutes), with blood loss of 50 (80) ml (range: 20 to 100 ml). For 8 patients in the non-division group who only underwent pyeloureteroplasty, the operation time was (98±27) minutes (range: 60 to 135 minutes), with blood loss of 20 (50) ml (range: 10 to 100 ml). The follow-up time of patients after surgery was 16.0 (49.0) months (range: 1.7 to 84.2 months), with a surgical success rate of 100%. Among the 8 patients in the non-division group, all demonstrated significant improvement in hydronephrosis severity compared to preoperative conditions. Notably, 6 patients who previously experienced frequent lower back pain showed no recurrence of symptoms after ureteral stent removal. In the division group of 15 patients, both subjective symptoms and hydronephrosis severity were markedly reduced. Conclusion:For patients with horseshoe kidney and hydronephrosis, the choice of surgical approach and isthmus management strategy should be determined based on a comprehensive consideration of the etiology of hydronephrosis, the degree of ureteral stricture, anatomical abnormalities, and vascular variations.

Objective: To explore the safety and feasibility of the disconnection of the left renal artery preferentially during robot-assisted inferior vena cava (IVC) thrombectomy for patients with left renal cell carcinoma and tumor emboli. Methods: Clinical data of 7 patients who underwent robot-assisted IVC thrombectomy and radical nephrectomy in the First Affiliated Hospital of Zhengzhou University during Dec.2021 and Oct.2024 were retrospectively analyzed.Thrombectomy was performed first，followed by nephrectomy. The “IVC-first, kidney-last”robotic technique was developed to minimize chances of IVC thrombus. When patients in left lateral decubitus position, the left renal artery was severed from the right side through the inferior vena cava and abdominal aorta. After removal of thrombus from IVC was completed, patients changed to the right lateral position to complete radical left nephrectomy. Results: Imaging examinations revealed that the median diameter of the renal cell carcinomas was 83(46-99) mm; the median length of the inferior vena cava cancerous emboli was 49(2-91) mm.According to the Mayo classification，the cancerous emboli were gradeⅠ in 2 cases，gradeⅡ in 4 cases，and grade Ⅲ in 1 case.All surgeries were successful.The median operation time was 248(201-331) minutes，blood loss 500(200-1000) mL，and 6 cases required intraoperative blood transfusion.The median time for transition into the intensive care unit was 1(1-4) days，and drainage tube removal 6(5-12) days.Serum creatinine increased significantly in 5 cases，4 of which returned to normal after 1 week，but 1 had renal insufficiency (creatinine 166 μmol/L).Chylous fistula occurred in 1 patient，and lower extremity venous thrombosis developed in 3 patients.Pathological examinations indicated 6 cases of renal cell carcinoma and 1 case of MiT family translocation renal cell carcinoma.During the median follow-up of 17(1-35) months，5 cases were tumor-free，while 2 had lung and retroperitoneal metastases.They received targeted therapy of axitinib combined immunotheraphy and lived with tumors. Conclusion: In the left lateral position for left renal cell carcinoma with cancerous emboli，robot-assisted laparoscopic thrombectomy by crossing the inferior vena cava and abdominal aorta and disconnecting the left renal artery first is safe and feasible.

Ureteral stricture is a common urological condition，whose treatment mainly depends on the etiology，location，number，and length of the stricture.For complex long-segment ureteral stricture，the main surgical procedures include endourological treatment，flap pyeloplasty，ureterocalicostomy，buccal mucosal ureteroplasty，lingual mucosal ureteroplasty，bladder mucosal ureteroplasty，appendiceal ureteroplasty，bladder flap ureteroplasty，and ileal ureter substitution ureteroplasty.Although open and laparoscopic surgeries are still prevalent，robotic surgery is gaining popularity due to its minimally invasive nature and precision.Based on the latest clinical advances and diagnostic and therapeutic experience of our team，we will systematically introduce the new surgical techniques and methods for the treatment of long-segment ureteral stricture from a clinical practical perspective.In addition，we will discuss the advantages and disadvantages of different autologous tissue reconstruction techniques，as well as the choices between minimally invasive and open surgery.

Objective: To compare peritoneal indexes between transperitoneal approach and retroperitioneal approach of robot-assisted partial nephrectomy (RAPN) for dorsal renal tumors via transperitoneal and retroperitoneal approaches，thereby providing reference for clinical decision-making in managing such neoplasms. Methods: The clinical data of renal cancer patients undergoing RAPN performed by the same surgeon at our hospital during 2017 and 2021 were retrospectively analyzed.A total of 80 patients with complete data of dorsal renal tumors were screened and divided into two groups based on the surgical approaches：50 cases in the transperitoneal group and 30 in the retroperitoneal group.The general information，intraoperative data，positive rate of pathological margins，recovery time of gastrointestinal functions，and incidence of complications were compared between the two groups. Results: All operations were successfully completed, and the surgical margins were negative.There were no statistically significant differences in warm ischemia time [17 (15，18) min vs.16 (14，19) min，P=0.772]，operation time [120 (105，149) min vs.124 (108，152) min，P=0.584]，intraoperative blood loss [100 (50，100) mL vs.100 (50，100) mL，P=0.814]，and incidence of postoperative complications (17% vs.24%，P=0.504) between the two groups (P>0.05).The postoperative recovery time of gastrointestinal functions in the retroperitoneal group was significantly shorter than that in the transperitoneal group [2.0 (2.0，3.0) d vs.3.5 (3.0，4.0) d，P<0.001]. Conclusion: The perioperative outcomes of patients undergoing RAPN via the retroperitoneal approach are similar to those via the transperitoneal approach.However，the retroperitoneal approach has an advantage of faster recovery of gastrointestinal functions.

Objective:To investigate the efficacy of a predictive model for differentiating benign and malignant renal tumors based on CT radiomic features and clinical features.Methods:A retrospective study was conducted on 1 395 patients with renal tumors admitted to the First Affiliated Hospital of Zhengzhou University from December 2011 to December 2021, including 842 males and 553 females. The median age was 55 (44, 59) years, and the median tumor diameter was 3.6 (2.7, 4.6) cm. All patients underwent contrast-enhanced CT scaning before surgery, and radiomic features were extracted from non-contrast, arterial, and venous phase images. Prediction models for distinguishing benign and malignant renal tumors were constructed using five machine learning algorithms (logistic regression, support vector machine, neural network, random forest, and extreme gradient boosting), and these models were then ensembled to construct a stacking classifier. All patients underwent partial nephrectomy, and they were divided into a training group (941 cases, December 2011 to June 2020) and a validation group (454 cases, July 2020 to December 2021) based on the date of surgery. A clinical-radiomic model was developed by combining the result of stacking classifier, clinical features and CT report results, and its predictive performance was evaluated in the validation group.Results:The radiomic signature based on the combined features and five machine learning algorithms(AUC 0.835-0.844) showed higher accuracy in predicting benign and malignant renal tumors compared to single phases (AUC 0.744-0.831). After integrating the five machine learning algorithms, the AUC of the three-phase combined radiomic model in the validation group improved to 0.847(95% CI 0.802-0.892). The clinical-radiomic model, incorporating radiomic features, clinical features, and CT report results, achieved a significantly higher AUC in the validation group compared to radiologists [0.919(95% CI 0.889-0.950)vs. 0.835(95% CI 0.786-0.883), P<0.01]. Conclusions:The predictive model integrating CT radiomics features, clinical characteristics, and CT report results demonstrates excellent discriminative ability in distinguishing benign and malignant renal tumors.

Objective:To analyze the clinical features associated with pelvic lymph node metastasis(PLNM)in prostate cancer and to construct a preoperative prediction model for PLNM,thereby reducing unnecessary extended pelvic lymph node dissection(ePLND).Methods:Based on predefined inclusion and exclusion criteria,344 patients who underwent radical prostatectomy and ePLND at the First Affilia-ted Hospital of Zhengzhou University between 2014 and 2024 were retrospectively enrolled,among whom,77 patients(22.4％)were pathologically confirmed to have lymph node-positive disease.The clinical characteristics,MRI reports,and pathological results were collected.The data were then randomly divi-ded into a training cohort(241 cases,70％)and a validation cohort(103 cases,30％).Univariate and multivariate Logistic regression analysis were employed to construct a preoperative prediction model for PLNM.Results:Univariate Logistic regression analysis revealed that total prostate specific antigen(tPSA)(P=0.021),free prostate specific antigen(fPSA)(P=0.002),fPSA to tPSA ratio(fPSA/tPSA)(P=0.011),percentage of positive biopsy cores(P＜0.001),prostate imaging reporting and data system(PI-RADS)score(P=0.004),biopsy Gleason score ≥8(P=0.005),clinical T stage(P＜0.001),and MRI-indicated lymph node involvement(MRI-LNI)(P＜0.001)were significant predictors of PLNM.Multivariate Logistic regression analysis demonstrated that the percentage of positive biopsy cores(OR=91.24,95％CI:13.34-968.68),PI-RADS score(OR=7.64,95％ CI:1.78-138.06),and MRI-LNI(OR=4.67,95％ CI:1.74-13.24)were independent risk factors for PLNM.And a novel nomogram for predicting PLNM was developed by integrating all these three variables.Com-pared with the individual predictors:percentage of positive biopsy cores[area under curve(AUC)=0.806],PI-RADS score(AUC=0.679),and MRI-LNI(AUC=0.768),the multivariate model incor-porating all three variables demonstrated significantly superior predictive performance(AUC=0.883).Consistently,calibration curves and decision curve analyses confirmed that the multivariable model had high predictive accuracy and provided significant net clinical benefit relative to single-variable models.And using a cutoff of 6％,the multiparameter model missed only approximately 5.2％of PLNM cases(4/77),while reducing approximately 53％of ePLND procedures(139/267),demonstrating favorable predictive efficacy.Conclusion:Percentage of positive biopsy cores,PI-RADS score and MRI-LNI are independent risk factors for PLNM.The constructed multivariate model significantly improves predictive efficacy,offering a valuable tool to guide clinical decisions on ePLND.

Objective:To analyze the clinical features associated with pelvic lymph node metastasis(PLNM)in prostate cancer and to construct a preoperative prediction model for PLNM,thereby reducing unnecessary extended pelvic lymph node dissection(ePLND).Methods:Based on predefined inclusion and exclusion criteria,344 patients who underwent radical prostatectomy and ePLND at the First Affilia-ted Hospital of Zhengzhou University between 2014 and 2024 were retrospectively enrolled,among whom,77 patients(22.4％)were pathologically confirmed to have lymph node-positive disease.The clinical characteristics,MRI reports,and pathological results were collected.The data were then randomly divi-ded into a training cohort(241 cases,70％)and a validation cohort(103 cases,30％).Univariate and multivariate Logistic regression analysis were employed to construct a preoperative prediction model for PLNM.Results:Univariate Logistic regression analysis revealed that total prostate specific antigen(tPSA)(P=0.021),free prostate specific antigen(fPSA)(P=0.002),fPSA to tPSA ratio(fPSA/tPSA)(P=0.011),percentage of positive biopsy cores(P＜0.001),prostate imaging reporting and data system(PI-RADS)score(P=0.004),biopsy Gleason score ≥8(P=0.005),clinical T stage(P＜0.001),and MRI-indicated lymph node involvement(MRI-LNI)(P＜0.001)were significant predictors of PLNM.Multivariate Logistic regression analysis demonstrated that the percentage of positive biopsy cores(OR=91.24,95％CI:13.34-968.68),PI-RADS score(OR=7.64,95％ CI:1.78-138.06),and MRI-LNI(OR=4.67,95％ CI:1.74-13.24)were independent risk factors for PLNM.And a novel nomogram for predicting PLNM was developed by integrating all these three variables.Com-pared with the individual predictors:percentage of positive biopsy cores[area under curve(AUC)=0.806],PI-RADS score(AUC=0.679),and MRI-LNI(AUC=0.768),the multivariate model incor-porating all three variables demonstrated significantly superior predictive performance(AUC=0.883).Consistently,calibration curves and decision curve analyses confirmed that the multivariable model had high predictive accuracy and provided significant net clinical benefit relative to single-variable models.And using a cutoff of 6％,the multiparameter model missed only approximately 5.2％of PLNM cases(4/77),while reducing approximately 53％of ePLND procedures(139/267),demonstrating favorable predictive efficacy.Conclusion:Percentage of positive biopsy cores,PI-RADS score and MRI-LNI are independent risk factors for PLNM.The constructed multivariate model significantly improves predictive efficacy,offering a valuable tool to guide clinical decisions on ePLND.

Objective:To investigate the efficacy of a predictive model for differentiating benign and malignant renal tumors based on CT radiomic features and clinical features.Methods:A retrospective study was conducted on 1 395 patients with renal tumors admitted to the First Affiliated Hospital of Zhengzhou University from December 2011 to December 2021, including 842 males and 553 females. The median age was 55 (44, 59) years, and the median tumor diameter was 3.6 (2.7, 4.6) cm. All patients underwent contrast-enhanced CT scaning before surgery, and radiomic features were extracted from non-contrast, arterial, and venous phase images. Prediction models for distinguishing benign and malignant renal tumors were constructed using five machine learning algorithms (logistic regression, support vector machine, neural network, random forest, and extreme gradient boosting), and these models were then ensembled to construct a stacking classifier. All patients underwent partial nephrectomy, and they were divided into a training group (941 cases, December 2011 to June 2020) and a validation group (454 cases, July 2020 to December 2021) based on the date of surgery. A clinical-radiomic model was developed by combining the result of stacking classifier, clinical features and CT report results, and its predictive performance was evaluated in the validation group.Results:The radiomic signature based on the combined features and five machine learning algorithms(AUC 0.835-0.844) showed higher accuracy in predicting benign and malignant renal tumors compared to single phases (AUC 0.744-0.831). After integrating the five machine learning algorithms, the AUC of the three-phase combined radiomic model in the validation group improved to 0.847(95% CI 0.802-0.892). The clinical-radiomic model, incorporating radiomic features, clinical features, and CT report results, achieved a significantly higher AUC in the validation group compared to radiologists [0.919(95% CI 0.889-0.950)vs. 0.835(95% CI 0.786-0.883), P<0.01]. Conclusions:The predictive model integrating CT radiomics features, clinical characteristics, and CT report results demonstrates excellent discriminative ability in distinguishing benign and malignant renal tumors.