Bilateral Wilms tumor: 10-year experience from a single center in China.

Background: Nephron sparing surgery (NSS) had become the main surgical treatment for bilateral nephroblastoma. But it remained a challenge for surgeons to balance the dilemma between complete tumor resection to reduce tumor recurrence and renal parenchyma preservation to reduce end-stage renal disease (ESRD). In this study, we summarized our clinical experience for bilateral Wilms tumors managed in our center and evaluated the influence of different surgical approaches on prognosis. Methods: The clinical data of patients with bilateral Wilms tumor in our hospital from January 2010 to December 2020 were retrospectively analyzed, and the clinical symptoms, surgical approaches and prognosis of the disease were summarized. Results: We reviewed medical records of 16 patients, including 13 (81.3%) girls and 3 (18.7%) boys. The mean age of the patients was 17.88±11.65 months (range, 6-42 months). Five patients presented with hypertension and two presented with hemihypertrophy. Fifteen cases had synchronous tumors, while only one patient had metachronous bilateral lesions. Thirteen patients received neoadjuvant chemotherapy and only 8 kidneys (30.8%) responded to chemotherapy. Two patients gave up surgery, and the other fourteen patients underwent radical resection, of which 2 patients only underwent unilateral radical nephrectomy (RN); 7 and 5 patients underwent single-stage and two-stage operation for bilateral lesions, respectively. In all surgical patients, RN was performed on 5 kidneys, and NSS was performed on 21 kidneys. The positive margins after NSS were found in 6 kidneys (35.3%). After a median follow-up period of 26.3 months, local tumor recurrence and renal insufficiency occurred in two and one patients. The 5-year overall and event-free survival rates were 78.1% and 58.6%, respectively. In univariable analysis, the survival rate in the initial chemotherapy group (92.3%) was significantly higher than that in the initial surgery group (33.3%) (P=0.048), whereas positive margin and staged operation (P>0.05) appeared not significantly associated with overall survival. Conclusions: The proportion of tumor reduction after preoperative chemotherapy is relatively low for bilateral Wilms tumor, but preoperative chemotherapy could improve overall survival. NSS is recommended for bilateral Wilms tumor, and the customized procedure can be selected according to the location and anatomical features of tumor.

Clinical and pathological characteristics of renal cell carcinomas with MiTF translocation.

INTRODUCTION: Microphthalmia Transfactor Family (MiTF) translocation renal cell carcinomas (RCCs) represent a rare subtype of renal cell cancers. They are diagnosed in young patients and have a poor prognosis. The aim of our study was to analyze the clinical and pathological features of patients with MiTF RCC. MATERIAL AND METHOD: We performed a retrospective, monocentric, descriptive study including all patients operated for RCC between January 2015 and January 2023. The diagnosis of MiTF RCC was suspected by immunohistochemistry (IHC) and confirmed by fluorescent in situ hybridization (FISH). Survival data according to histological subtype (MiTF versus ccRCC) were analyzed using the Kaplan-Meier method and compared using a log-rank test. The primary endpoint was recurrence-free survival (RFS). A descriptive cohort analysis was performed. RESULTS: Of the 960 patients included, 19 (2%) had FISH-confirmed MiTF tumors. The median age at diagnosis was 42 years [18-75], the sex ratio was 1.11 females for 1 male, and 4 (21%) patients were immediately metastatic. Median RFS was 21months for patients in the MiTF group and was significantly lower than that of ccRCC patients, HR=4.33 [CI95% 2.06; 9.10; P<0.001]. Of the 11 patients with cT1-T2 tumors, 9 (81.8%) were treated with nephron sparing-surgery, with 2 (22.2%) harbored local recurrence. CONCLUSION: Our study shows that patients with MiTF translocation RCC have a significantly lower RFS than non-MiTF RCC patients. Nephron sparing surgery must be weighted by the high risk of recurrence in this particularly young population.

A radiomics nomogram for preoperative prediction of nephron-sparing surgery in patients with bilateral Wilms tumor.

Background: Bilateral Wilms tumor (BWT) is a relatively rare malignant renal tumor in children. Nephron-sparing surgery (NSS) is the preferred surgical approach for treating BWT, but lacks uniform surgical indications worldwide. This study aimed to summarize the clinical and imaging features of BWT children, establish a radiomics nomogram, and predict the feasibility of NSS for improving outcomes. Methods: A 12-year retrospective single-center review was conducted on clinical data and preoperative imaging features of BWT patients. The tumor kidneys were divided into NSS and non-NSS groups. Logistic regression analysis was performed to identify independent predictors and develop a prediction model of the feasibility of NSS in BWT patients. A radiomics nomogram was constructed and internally validated by the parametric bootstrapping method. Results: A total of 58 BWT patients (115 renal units) were included in this study. After evaluations based on preoperative imaging and clinical data, 94 renal units underwent NSS with negative resection margins and were included in the NSS group, whereas 16 renal units with positive resection margins, macroscopic residual, or total nephrectomies were included in the non-NSS group. Tumor size [odds ratio (OR): 0.540, 95% confidence interval (CI): 0.308-0.945], relationship with the collecting system (OR: 0.013, 95% CI: 0.0004-0.370), and remaining renal parenchyma (RRP) proportion (OR: 71.23, 95% CI: 1.632-3108.8) were identified as independent predictors for NSS. A nomogram was constructed based on these factors, which demonstrated great consistency between the predicted and observed feasibility of NSS. The model presented with good discriminative ability [area under the curve (AUC), 0.982]. The decision curve analysis (DCA) revealed the clinical usefulness of the model. Conclusions: This study analyzed the clinical and preoperative imaging data of BWT patients and identified three independent predictors for the feasibility of NSS, including tumor size, relationship with the collecting system, and residual renal parenchyma proportion. The radiomics nomogram established in this study can provide individualized predictions to assist clinicians in making better decisions and improving patient outcomes.

Clinical application of superselective transarterial embolization of renal tumors in zero ischaemia robotic-assisted laparoscopic partial nephrectomy.

Objective: To assess the feasibility and safety of zero ischaemia robotic-assisted laparoscopic partial nephrectomy (RALPN) after preoperative superselective transarterial embolization (STE) of T1 renal cancer. Methods: We retrospectively analyzed the data of 32 patients who underwent zero ischaemia RALPN after STE and 140 patients who received standard robot-assisted laparoscopic partial nephrectomy (S-RALPN). In addition, we selected 35 patients treated with off-clamp RALPN (O-RALPN) from September 2017 to March 2022 for comparison. STE was performed by the same interventional practitioner, and zero ischaemia laparoscopic partial nephrectomy (LPN) was carried out by experienced surgeon 1-12 hours after STE. The intraoperative data and postoperative complications were recorded. The postoperative renal function, routine urine test, urinary Computed Tomography (CT), and preoperative and postoperative glomerular filtration rate (GFR) data were analyzed. Results: All operations were completed successfully. There were no cases of conversion to opening and no deaths. The renal arterial trunk was not blocked. No blood transfusions were needed. The mean operation time was 91.5 ± 34.28 minutes. The mean blood loss was 58.59 ± 54.11 ml. No recurrence or metastasis occurred. Conclusion: For patients with renal tumors, STE of renal tumors in zero ischaemia RALPN can preserve more renal function, and it provides a safe and feasible surgical method.

Bench surgery with autotransplantation for bilateral Wilms tumor-A feasible technique for renal sinus invasion.

Purpose: Bilateral Wilms tumor (BWT) with renal sinus invasion requires extremely difficult surgical care. This study presents an alternative strategy for tumor removal while at the same time preserving the renal parenchyma. Materials and methods: In total, 9 cases of synchronous BWT were admitted to our hospital between May 2016 to Aug 2020. We retrospectively reviewed the clinical data, surgical technique, and functional and oncological outcomes of these cases. Results: The 9 cases included 3 males and 6 females, with a median age of 12 months at surgery (range 7-40). A total of 14 kidney units had renal sinus invasion (77.8%), whereas multifocal neoplasms were observed in 7 units (38.9%). The local stage distribution revealed 1 kidney with stage I, 10 kidneys with stage II, and 7 kidneys with stage III. Nephron-sparing surgery was performed on 15 kidney units (83.3%), among which 13 (72.2%) underwent bench surgery with autotransplantation (BS-AT), whereas 2 (11.1%) were subjected to tumor enucleation in vivo. Urinary leakage was the most prevalent postoperative complication. We observed negative margins. During the mean follow-up of 28.4 months, 2 patients (22.2%) succumbed from sepsis and renal failure, respectively, whereas the other 7 (77.8%) survived without recurrence. Survivors experienced an estimated glomerular filtration rate of 81 ± 15.4 ml/(min × 1.73 m2). The endpoint renal volume of 9 renal units receiving BS-AT significantly increased (P = 0.02). Conclusions: In summary, the surgical management of bilateral Wilms tumor requires meticulous operative approach and technique. Besides, BS-AT provides a viable alternative to nephron-sparing surgery for BWT patients with renal sinus invasion.

Case Report: MRI, CEUS, and CT Imaging Features of Metanephric Adenoma with Histopathological Correlation and Literature Review.

The metanephric adenoma is an extremely rare, benign, embryonal-epithelial neoplasm of the kidney and has a good prognosis with appropriate treatment. It can present at any age and is often asymptomatic. Histologically, the lesion is well established; however, there have been only a few cases described with available detailed imaging findings, most of them with large renal masses typically depicted by computed tomography (CT). This case report includes imaging of contrast-enhanced MRI, contrast-enhanced ultrasound (CEUS), and CT, and thus adds to the information available, potentially promoting a nephron-sparing clinical pathway. We report on the clinical presentation, imaging, histopathological diagnosis, and treatment data of a 27-year-old female, in whom an incidental, symptomatic kidney tumor was detected. CT, CEUS, and MRI showed a suspicious unifocal renal lesion with inhomogeneous enhancement, which was indistinguishable from renal cell carcinoma. After laparoscopic resection, a metanephric adenoma with microscopically partially glandular, partially nest-like solid growth and without distinctive atypia was diagnosed pathohistologically. Immunohistochemistry results were positive for Wilms Tumor 1 and CD57 and negative for EMA and CK7: 2-3% positive cells in MIB1 coloring. At 3-month and 1-year follow-up, the patient was asymptomatic and imaging showed no recurrence of renal masses or metastases.

Mixed reality models based on low-dose computed tomography technology in nephron-sparing surgery are better than models based on normal-dose computed tomography.

BACKGROUND: Nephron-sparing surgery has been widely applied in the treatment of renal tumors. Previous studies have confirmed the advantages of mixed reality technology in surgery. The study aimed to explore the optimization of mixed reality technology and its application value in nephron-sparing surgery. METHODS: In this prospective study of 150 patients with complex renal tumors (RENAL nephrometry score ≥7) who underwent nephron-sparing surgery, patients were randomly divided into Group A (the normal-dose mixed reality group, n=50), Group B (the low-dose mixed reality group, n=50), and Group C (the traditional computed tomography image group, n=50). Group A and Group C received the normal-dose computed tomography scan protocol: 120 kVp, 400 mA, and 350 mgI/mL, while Group B received the low-dose computed tomography scan protocol: 80 kVp, automatic tube current modulation, and 320 mgI/mL. All computed tomography data were transmitted to a three-dimensional visualization workstation and underwent modeling and mixed reality imaging. Two senior surgeons evaluated mixed reality quality. Objective indexes and perioperative indexes were calculated and compared. RESULTS: Compared with Group A, the radiation effective dose in Group B was decreased by 39.6%. The subjective scores of mixed reality quality in Group B were significantly higher than those of Group A (Z=-4.186, P<0.001). The inter-observer agreement between the two senior surgeons in mixed reality quality was excellent (K=0.840, P<0.001). The perioperative indexes showed that the mixed reality groups were significantly different from the computed tomography image group (all P<0.017). More cases underwent nephron-sparing surgery in the mixed reality groups than in the computed tomography image group (P<0.0017). CONCLUSIONS: Low-dose computed tomography technology can be effectively applied to mixed reality optimization, reducing the effective dose and improving mixed reality quality. Optimized mixed reality can significantly increase the cases of successful nephron-sparing surgery and improve perioperative indexes.

Surgical margin follow-up after nephron-sparing surgery: the possible role of CEUS.

PURPOSE: To evaluate the possible role of CEUS in the management of patients who underwent nephron-sparing surgery (NSS) and presented questionable findings on the surgical margins at the CECT follow-up exam. METHODS: In our retro-prospective study, we included 952 patients with small renal masses (SRMs) treated with NSS between 2012 and 2015 and followed with CECT for at least 3 years at Careggi University Hospital. Twenty-two of them presented solid masses on the site of surgery with questionable enhancement at CECT and were further studied with CEUS. This examination was followed by a quantitative analysis of the enhancement pattern. RESULTS: Out of the 22 masses, 18 were considered possible granulomas, presenting slow wash-in and low enhancement peaks compared to the surrounding parenchyma and persistent delayed wash-out at CEUS. Four lesions presented a suspicious malignant enhancement pattern, with rapid wash-in, high peak and rapid wash-out. In accordance with instructions from the urologist, the first group of 18 patients was strictly monitored, revealing that the mass dimensions and enhancement pattern were stable for at least 3 years of follow-up, while the other 4 patients underwent a second intervention and their masses were confirmed as tumor recurrence at the histopathological evaluation. CONCLUSIONS: CEUS can play a key role in the surgical margin follow-up after NSS when a suspicious enhancing mass is detected by CECT, giving an accurate depiction of the enhancement pattern and thus helping the clinician in the management of the patient.

Wilms tumor: a review of current surgical controversies.

Overall survival (OS) for children with Wilms tumor (WT) currently stands at around 90%. This is markedly improved from the survival rates of around 30% reported in the middle of the last century. This improvement is due to the development of multimodal treatment for this disease, based on the evidence yielded through international collaboration on trials conducted by the Société Internationale d'Oncologie Pédiatrique (SIOP) and the Children's Oncology Group (COG). In this article, we review some of the current surgical controversies surrounding the management of WT.

Nephron-sparing surgery for the management of upper tract urothelial carcinoma: an outline of surgical technique and review of outcomes.

Upper tract urothelial carcinoma (UTUC) often occurs in elderly patients with multiple co-morbidities including renal impairment. As such, nephron sparing surgery (NSS) often needs to be considered. This article reviews the available NSS techniques for UTUC, including ureteroscopy, percutaneous approaches and segmental ureterectomy. PubMed and OvidMEDLINE reviews of available case series from the last 10 years demonstrated that recurrence was highly variable between studies and occurred in 19-90.5% of ureteroscopic cases, 29-98% of percutaneous resections and in 10.2-31.4% of patients who underwent segmental ureterectomy. The small number of included studies and variable follow up periods made comparison between techniques difficult. NSS is a necessary alternative for patients with significant comorbidities or renal impairment who cannot undergo radical nephro-ureterectomy. However, there is significant variation in oncological outcomes, with an increased risk of progression or death from cancer-salvage by radical surgery may sometimes be required.

Establishment of a novel system for the preoperative prediction of adherent perinephric fat (APF) occurrence based on a multi-mode and multi-parameter analysis of dual-energy CT.

BACKGROUND: Adherent perinephric fat (APF) is evaluated preoperatively with the Mayo adhesive probability (MAP) scoring system using conventional single-form computed tomography (CT) images. An objective or quantitative indicator for predicting APF is urgently needed for clinical application. METHODS: A total of 150 patients with renal tumours who underwent laparoscopic partial nephrectomy (LPN) were retrospectively enrolled and divided into the APF group (n=100) and the non-APF group (n=50) according to surgical results. All patients underwent a renal contrast-enhanced dual-energy CT (DECT) scan. The obtained CT DICOM data were transmitted to the DECT post-processing workstation and adopted virtual non-contrast (VNC), Rho/Z Maps, and Monoenergetic Plus (mono+) modes separately to undergo a multi-parameter analysis. A logistic stepwise investigation was utilized to analyse the related risk factors. The cutoff value was determined by the Youden index. Fifty patients were prospectively enrolled to validate the constructed model. The area under the curve (AUC), sensitivity, specificity and accuracy of the model were calculated. RESULTS: The study demonstrated that age, sex, body mass index (BMI), smoking status, tumour diameter, exophytic status, degree of malignancy and posterior perinephric fat thickness were related to the occurrence of APF (P<0.05). Model 1 was selected with the contrast material (CM) parameter (cutoff point 0.5), model 2 was selected with the effective atomic number (Zeff) parameter (cutoff point 6.5), and model 3 was selected with the slope K (K) parameter (cutoff point -0.95). The AUC, sensitivity, specificity and accuracy of model 1 were 0.94, 0.94, 0.93 and 0.94, respectively; for model 2, they were 0.94, 0.93, 0.93 and 0.96, respectively; and for model 3, they were 0.92, 0.92, 0.93 and 0.92, respectively. CONCLUSIONS: Multi-mode and multi-parameter models of DECT can effectively be used to predict the occurrence of APF.

The impact of comorbidities, sex and age on the occurrence of acute kidney injury among patients undergoing nephron-sparing surgery.

BACKGROUND: The aim of this study was to report the impact of patients' baseline characteristics on the incidence of acute kidney injury (AKI) after nephron-sparing surgery (NSS) for localized kidney cancer. PATIENTS AND METHODS: Data from our kidney cancer database were retrospectively extracted to include 402 patients who underwent NSS between March 2000 and June 2016, and had sufficient data. Definition of AKI was based on the postoperative serum creatinine levels and estimated glomerular filtration rate (eGFR) magnitude, which were measured during the 72 h after surgery. RESULTS: Based on RIFLE and AKIN criteria, the overall rate of postoperative AKI was 35%. The average decrease in eGFR among patients who developed AKI was 20% as compared with the non-AKI subgroup (2%). In univariate analysis, variables that were associated with AKI included right-sided tumors (p = 0.014), male sex (p = 0.01), hypertension (p = 0.003), baseline eGFR (p = 0.009) and history of nephrolithiasis (p = 0.039). However, multivariate analysis revealed that the only independent predictors of postoperative AKI were hypertension (p = 0.009) and cigarette smoking (p = 0.024). CONCLUSION: AKI is a common complication of NSS affecting about one-third of the patients. The most important risk factors are hypertension and smoking.

Incidence, characteristics, treatment strategies, and oncologic outcomes of synchronous bilateral upper tract urothelial carcinoma in the Chinese population.

OBJECTIVES: To investigate the incidence and treatment strategies for bilateral upper tract urothelial carcinoma (UTUC) and to compare the characteristic and oncologic outcomes of bilateral UTUC with those of unilateral tumors. METHODS AND MATERIALS: The study included 892 consecutive patients with UTUC. Bilateral UTUC was defined as synchronous bilateral carcinoma on preoperative imaging before confirmation by pathology or positive urine cytology result plus direct visualization. Radical nephroureterectomy (RNU) or nephron-sparing surgery (NSS) or both were carried out. RESULTS: A total of 39 patients (4.37%) suffered from bilateral disease. Discordant histological grade of bilateral tumor was found in 39.3% cases. Bilateral tumors were associated with female sex (P<0.001), preoperative renal insufficiency (P<0.001), previous or concomitant bladder tumors (P = 0.013), lower tumor stages (P = 0.020), papillary architecture (P = 0.001), and smaller-sized tumors (P = 0.020). Patients with worse renal function (P<0.001) or large-sized tumors (P = 0.039) tended to be treated with bilateral RNU. Most patients (67.6%) were treated with unilateral RNU plus unilateral NSS, with NSS being performed on tumors that only extended to the ureter (P = 0.003) and had a smaller size (P = 0.005). The median follow-up duration was 56 months. The 5-year cancer-specific survival and bladder recurrence-free survival rates were 81.2% and 64.5%, respectively, similar to those of unilateral tumors. Male sex (hazard ratio = 11.535) and higher tumor stage (hazard ratio = 3.386) were independent worse prognostic factors. CONCLUSIONS: The prevalence of bilateral UTUC is rare. Female patients, patients with renal insufficiency, and those with bladder tumor tended to suffer from bilateral disease and were less likely to present with worse pathological outcomes in the Chinese population. The tumor characteristics and renal function were informative in treatment selection. The oncologic outcomes were similar to those in unilateral UTUC, and male sex and a higher tumor stage were poor prognostic factors for these patients.

Renal function after nephron-sparing surgery for renal tumors.

Nephron sparing surgery (NSS) is a technique more frequently utilized in the case of surgical treatment of kidney tumor. The aim of the study is to assess renal function in patients treated with NSS for renal tumors. Twenty patients, after NSS performed for renal tumor, were included in the study. In each patient dynamic renal scintigraphy was performed before surgical treatment (test No. 1) and after a mean interval of 12 months after surgical procedure (test No. 2). In each test renographic curves were evaluated. Creatinine levels and GFR rates were also assessed. Mean GFR was 84 ml/min/1.73 m(2) before surgery, and 79 ml/min/1.73 m(2) after surgical procedure. Mean change of GFR value after the surgical procedure was -5.1 (p >0.058). On renography significant deterioration of renal function was observed in the operated kidneys of 4 patients (20%) after NSS, insignificant deterioration - in four patients (20%) and improvement of renal function of operated kidney was found in one patient. In 12 patients (60%) no change was observed. The relative percentage GFR-share of operated kidney decreased by the average value of 3.8% (p >0.005). Multifactorial analysis did not identify significant effect of potential risk factors on the function of the kidney subjected to NSS. Preliminary results of this study confirm that deterioration of renal function after NSS is a rare event.