Disseminated adult Wilms tumor in pregnancy: Leveraging multidisciplinary care in a low-resource setting

Wilms tumor (WT) occurring in adults is rare and even much more rarely found to coexist with pregnancy. Clinical outcome in adults is worse overall compared with pediatric patients with WT and is often misdiagnosed with no standardized protocols for care guided by high-evidence clinical trials. We present a case of a 23-year-old woman diagnosed with WT who was found to be pregnant immediately following nephrectomy. Workup findings showed that she had disseminated disease but was successfully managed in a multidisciplinary team setting with modified intrapartum chemotherapy followed by postpartum chemotherapy. In low-resource settings, management protocols for adult patients with WT can be individualized by multidisciplinary teams to leverage available resources for best outcomes.

Intraoperative Ultrasound: Bridging the Gap between Laparoscopy and Surgical Precision during 3D Laparoscopic Partial Nephrectomies

The use of 3D laparoscopic partial nephrectomy has emerged as a cornerstone in the surgical arsenal for addressing renal tumors, particularly in managing challenging cases characterized by deeply seated tumors embedded within the renal parenchyma. In these intricate scenarios, the utilization of intraoperative ultrasound (IOUS) acquires paramount importance, serving as an indispensable tool for guiding and meticulously monitoring the surgical process in real time. To further explore the efficacy of IOUS-guided techniques, we conducted a retrospective study comparing outcomes in patients who underwent partial nephrectomy with IOUS guidance (n = 60) between 2020 and 2022 with a cohort from 2018 to 2019 without IOUS guidance (n = 25). Our comprehensive analysis encompassed various post-operative parameters, including the duration until food resumption, analgesia requirements, and length of the hospital stay. While these parameters exhibited comparable outcomes between the two groups, notable distinctions emerged in the intraoperative metrics. The IOUS-guided cohort demonstrated significantly reduced blood loss, a shorter median operative duration, and diminished ischemia time (p = 0.001). These compelling findings underscore the undeniable benefits of IOUS-guided techniques in not only facilitating the attainment of negative surgical margins but also in enhancing procedural safety and precision, thereby contributing to improved patient outcomes in the management of renal tumors.

Impacts of Complete Endophytic Renal Tumors on Surgical, Functional, and Oncological Outcomes of Robot-Assisted Partial Nephrectomy

Objective: Complete endophytic renal tumors (CERTs) are the most challenging for robot-assisted partial nephrectomy (RAPN). This study aimed to determine the impact of CERT on outcomes of RAPN. Methods: All RAPN cases for localized renal tumor undertaken at Yokohama City University Hospital between 2016 and 2023 were enrolled. Tumor characteristics and surgical, functional, and oncologic outcomes of RAPN were compared between CERT and non-CERT groups. Results: Consecutive 666 patients were enrolled, and 76 (11.4%) were identified as CERT (3 points of "E" score). CERT showed smaller tumor diameters (p < 0.001), more predominant hilar tumor (p = 0.029), higher "N" scores (p < 0.001) and "L" scores (p = 0.006) than non-CERT. The CERT group showed longer warm ischemia times (p < 0.001), more frequent positive surgical margins (p = 0.028), and relatively lower trifecta achievement rates (p = 0.101) than the non-CERT group. In multivariable analysis, the CERT was an independent predictor for trifecta achievement but not for pentafecta achievement. Conclusions: CERT was associated with longer warm ischemia time, positive surgical margin, and lower trifecta achievement, but not with surgical complication and pentafecta achievement in RAPN. This study suggested that CERT had limited influence on long-term renal functional preservation; however, it had strong impacts on short-term surgical outcome.

Papillary renal neoplasm with reverse polarity: an observational study of histology, immunophenotypes, and molecular variation

Background

Papillary renal neoplasm with reverse polarity (PRNRP) is a novel entity with unique clinicopathological characteristics, and only a small number of patients with PRNRP have been described.

Methods

We retrospectively analyzed the data for nine patients with PRNRP and evaluated differences in the clinical, histomorphological, immunohistochemical, and molecular features; prognosis; and differential diagnosis of PRNRP from other renal tumors with papillary structure.

Results

There were six males and three females aged 36 to 74 years (mean: 62.33 years; median: 68 years). All the tumors were solitary and ranged from 1 to 3.7 cm (mean: 2.17 cm; median: 2 cm), with three and six tumors arose in the left and right renal tract, respectively. Pathologically, PRNRP is a small, well-circumscribed neoplasm with predominant papillary formations. The lining epithelium is composed of a monolayer of cuboidal to low-columnar cells with low-grade nuclei arranged against the apical pole of the tumor cells. Edema, mucinous degeneration, and hyaline degeneration are found in the fibrovascular cores. Foamy macrophages, psammoma bodies, hemosiderin deposition, and infiltrative tumor boundaries were present in some patients. Immunohistochemically, all tumors showed diffuse positive staining for GATA3. Sanger sequencing confirmed the presence of KRAS mutation in seven patients. All patients had a good prognosis after surgery and were relapse free. Positive staining for GATA3 and negative staining for vimentin were the most significant markers for differentiating PRNRP from other renal tumors with analogous structure.

Conclusions

These findings suggested that PRNRP is a distinctive subtype of renal tumor with specific pathological features and indolent behaviors that should be distinguished from other renal tumors, especially papillary renal cell carcinoma. A monolayer of tumor cells with an inverted nuclear pattern, positive staining for GATA3, and KRAS mutation are essential for pathological diagnosis. Owing to its satisfactory prognosis, the surveillance and follow-up of patients with PRNRP should be additionally formulated.

Case report: Isolated eyelid metastasis of ccRCC 5 years after receiving radical nephrectomy

Introduction

The most common sites of clear cell renal cell carcinoma(ccRCC) metastasis are the lung, bones, liver and brain; eyelid metastasis is a rare occurrence.

Case presentation

We report a case of ccRCC metastasis to the left eyelid after radical nephrectomy, and remission after sunitinib treatment.

Conclusions

Although the probability of eyelid metastasis rate is very low, tumor metastasis to the eyelid skin is possible after radical nephrectomy. Therefore, any rash like changes on the skin during the review procedure cannot be ignored by the physician.

Ultrasound image segmentation of renal tumors based on UNet++ with fusion of multiscale residuals and dual attention

Objective. Laparoscopic renal unit-preserving resection is a routine and effective means of treating renal tumors. Image segmentation is an essential part before tumor resection. The current segmentation method mainly relies on doctors manual delineation, which is time-consuming, labor-intensive, and influenced by their personal experience and ability. And the image quality of segmentation is low, with problems such as blurred edges, unclear size and shape, which are not conducive to clinical diagnosis.Approach. To address these problems, we propose an automated segmentation method, i.e. the UNet++ algorithm fusing multiscale residuals and dual attention (MRDA_UNet++). It replaces two consecutive 3 × 3 convolutions in UNet++ with the 'MultiRes block' module, which incorporates coordinate attention to fuse features from different scales and suppress the impact of background noise. Furthermore, an attention gate is also added at the short connections to enhance the ability of the network to extract features from the target area.Main results. The experimental results show that MRDA_UNet++ achieves 93.18%, 92.87%, 93.66%, and 92.09% on the real-world dataset for MIoU, Dice, Precision, and Recall, respectively. Compared to the baseline model UNet++ on three public datasets, the MIoU, Dice, and Recall metrics improved by 6.00%, 7.90% and 18.09% respectively for BUSI, 0.39%, 0.27% and 1.03% for Dataset C, and 1.37%, 1.75% and 1.30% for DDTI.Significance. The proposed MRDA_UNet++ exhibits obvious advantages in feature extraction, which can not only significantly reduce the workload of doctors, but also further decrease the risk of misdiagnosis. It is of great value to assist doctors diagnosis in the clinic.

An Uncommon Presentation of Renal Angiomyolipoma: A Case Report

Renal angiomyolipoma (AML) is a rare benign tumor of the kidney that can occur as a sporadic lesion or a part of tuberous sclerosis. A 77-year-old female patient with a history of hypertension, hyperlipidemia, and an unclear history of left nephrectomy in 1999 presented with progressive shortness of breath and palpitations. Her vital signs showed elevated blood pressure, and the examination was benign and non-focal. A work-up showed multiple lesions in her lungs and right kidney, representing lymphangioleiomyomatosis. The patient was diagnosed with tuberous sclerosis and was followed up by pulmonology and nephrology. She underwent embolization of the renal AML, after which her blood pressure (BP) was more controlled, and she reported feeling well and symptom-free. Renal AML, as a part of tuberous sclerosis, is a rare cause of secondary hypertension. Embolization of AML is effective in controlling BP.

New cases of recently described Thauvin-Robinet-Faivre syndrome with a novel homozygous FIBP gene variant

Thauvin-Robinet-Faivre syndrome (#617107) is a rare autosomal recessive overgrowth syndrome characterized by intellectual disability, facial dysmorphism, macrocephaly, and variable congenital malformations. It is caused by homozygous or compound heterozygous FIBP gene mutations. The FIBP gene is located on the 11q13.1 region and codes the acidic fibroblast growth factor intracellular binding protein, which is involved in the fibroblast growth factor (FGF) signaling pathway. FGF signaling is required for neurogenesis and neuronal precursor proliferation. The FGF controls cell proliferation, differentiation, and migration in embryonic development and in adult life. Overgrowth syndromes consist of a wide spectrum disorders characterized by prenatal and postnatal excess growth in weight and length, often associated malformations, intellectual disability, and neoplastic predisposition. Embryonic tumors are especially common in these syndromes. Thauvin-Robinet-Faivre syndrome is a recently described overgrowth syndrome with typical facial dysmorphic and clinical features. To date, only four patients have been reported with this disorder. Herein, two new cases of Thauvin-Robinet-Faivre syndrome are reported with overgrowth, intellectual disability, typical dysmorphic signs in one dysplastic kidney, and a novel homozygous FIBP gene variant. Exome sequencing analysis showed that both affected siblings share the same homozygous c. 412-3_415dupCAGTTTG FIBP gene variant. Reporting two new cases with this rare autosomal recessive overgrowth syndrome with a novel FIBP gene variant will support and expand the clinical spectrum of Thauvin-Robinet-Faivre syndrome. Also discussed will be the function of FIBP in tumorigenesis and the possible renal tumor susceptibility in heterozygous carriers will be emphasized.

Polarization-sensitive optical coherence tomography for renal tumor detection in ex vivo human kidneys

Kidney cancer is a kind of high mortality cancer because of the difficulty in early diagnosis and the high metastatic dissemination in treatments. The surgical resection of tumors is the most effective treatment for renal cancer patients. However, precise assessment of tumor margins is a challenge during surgical resection. The objective of this study is to demonstrate an optical imaging tool in precisely distinguishing kidney tumor borders and identifying tumor zones from normal tissues to assist surgeons in accurately resecting tumors from kidneys during the surgery. 30 samples from six human kidneys were imaged using polarization-sensitive optical coherence tomography (PS-OCT). Cross-sectional, enface, and spatial information of kidney samples were obtained for microenvironment reconstruction. Polarization parameters (phase retardation, optic axis direction, and degree of polarization uniformity (DOPU) and Stokes parameters (Q, U, and V) were utilized for multi-parameter analysis. To verify the detection accuracy of PS-OCT, H&E histology staining and dice-coefficient was utilized to quantify the performance of PS-OCT in identifying tumor borders and regions. In this study, tumor borders were clearly identified by PS-OCT imaging, which outperformed the conventional intensity-based OCT. With H&E histological staining as golden standard, PS-OCT precisely identified the tumor regions and tissue distributions at different locations and different depths based on polarization and Stokes parameters. Compared to the traditional attenuation coefficient quantification method, PS-OCT demonstrated enhanced contrast of tissue characteristics between normal and cancerous tissues due to the birefringence effects. Our results demonstrated that PS-OCT was promising to provide imaging guidance for the surgical resection of kidney tumors and had the potential to be used for other human kidney surgeries in clinics such as renal biopsy.

Ex Vivo Partial Nephrectomy and Autotransplantation for Complex and Multifocal Renal Cell Carcinoma at a Single Institution: A Case Series

Renal autotransplantation is a rare surgical procedure designed to preserve renal function in patients with complex urinary system diseases or highly complex renal tumors. Between 2012 and 2023, four patients underwent ex vivo partial nephrectomy (PN) and autotransplantation for complex renal tumors at our hospital. Two patients had bilateral multifocal renal tumors, including von Hippel Lindau (VHL) disease and hybrid oncocytic chromophobe tumor (HOCT). The remaining two patients had highly complex renal tumors with Preoperative Aspects and Dimensions Used for an Anatomical (PADUA) score of 12, one of whom had a solitary kidney. None of the patients experienced any postoperative surgical complications. Pathologically, nine of the excised tumors had negative surgical margins, except for one of the four tumors on HOCT. Postoperative renal function decreased at one month compared to preoperative renal function (P = 0.01); however, there was no significant difference at three months (P = 0.07). None of the patients had a local recurrence or metastasis at the latest follow-up.Ex vivo PN and autotransplantation are feasible and reasonable treatment methods for highly complex and multifocal renal tumors regarding safety, local tumor control, and preservation of renal function.

Folliculin gene-negative Birt-Hogg-Dube syndrome: a case report

Introduction and importance

Birt-Hogg-Dube (BHD) is a rare genetic disorder that results from a mutation in the folliculin (FLCN) gene. Manifestations include pulmonary cysts, fibrofolliculomas, renal tumors, and pneumothoraces. Genetic testing can be used to confirm the diagnosis when suspected. BHD syndrome is diagnosed in patients with negative FLCN gene results using diagnostic criteria.

Case presentation

A male in his 20s presented with recurrent pneumothoraces. A physical examination revealed bumps on his face and upper body. A chest computed tomography scan revealed cystic lesions. Blood tests, ESR, and CRP levels were unremarkable. Punch skin biopsy revealed fibrofolliculomas. Genetic testing for the FLCN mutation returned negative. His history, physical exam, imaging, and histopathology suggested BHD syndrome despite having a negative family history and genetic analysis. Eventually, the patient was diagnosed with FLCN gene-negative BHD syndrome.

Clinical discussion

More than a hundred families have been identified to have BHD worldwide. There are a few cases in the literature describing patients phenotypically presenting with BHD despite having a negative genetic analysis. One study in Japan found 16 out of 157 individuals having a clinical presentation of BHD with no mutations. Also, decreased expression of the FLCN mRNA may lead to BHD.

Conclusion

BHD syndrome can present with a negative FLCN gene mutation; however, patients must meet the known diagnostic criteria such as criteria made by Menko et al., Gupta et al., and Schmidt et al. in order to have a diagnosis of BHD syndrome. Also, a qualitative decrease of FLCN with the absence of mutations may also lead to BHD.

Brain metastases with unusual MRI features in an infant with relapsed clear cell sarcoma of the kidney: A case report

Clear cell sarcoma of the kidney (CCSK) is a rare primary renal tumor in children. It is known for its propensity to metastasize to bones and lungs at initial diagnosis. Distant metastatic relapses occur in about 15-16% of the patients, with the brain being the most frequent site of relapse. Imaging features of brain metastases from CCSK have only been reported in a few cases and most reports lack a detailed description of the imaging findings. We present brain magnetic resonance imaging (MRI) findings in an infant with relapsed CCSK who developed multiple parenchymal metastases with concentric signal alterations and no tumor-associated edema.

Cystic partially differentiated nephroblastoma in an 18-month-old girl: a case report

Introduction and importance

Cystic partially differentiated nephroblastoma (CPDN) is a rare cystic tumor that affects the kidney. It has a low potential for malignancy. It usually presents as an abdominal mass. It may be difficult to confirm the diagnosis of CPDN without a histopathological study.

Case presentation

The authors report a case of an 18-month-old girl with abdominal distention, which was noticed by her parents. An abdominal computed tomography scan showed a large multilocular cystic mass arising from the lower pole of the left kidney. A left total nephrectomy was performed. Immature blastemal elements without evidence of malignant cells were observed on histological analysis.

Conclusion

The authors report a case of an 18-month-old girl with CPDN managed by total nephrectomy. CPDN should be considered in the differential diagnosis of patients with cystic renal lesions. The authors would also like to affirm that partial or total nephrectomy should be done in all cases of CPDN and other cystic renal tumors.

Surgery in Bilateral Wilms Tumor-A Single-Center Experience

The treatment of bilateral Wilms tumors (BWT) involves curing the cancer, preserving long-term renal function, and maintaining a good quality of life. Established methods for achieving these goals include preoperative chemotherapy and nephron-sparing surgery (NSS). This study aimed to evaluate the experience of a single institution in treating patients with BWT. We analyzed cases of BWT treated at the Pediatric Oncology Institute-GRAACC-Federal University of São Paulo over a period of 35 years. Bleeding control was performed with manual compression of the renal parenchyma. Thirty-three patients were included in the study. Thirty cases were synchronous tumors. The mean age at diagnosis was 30.4 months (±22 m) and 66.7% were girls. The median follow-up period was 83 months. Neoadjuvant chemotherapy was the primary approach in most patients (87.9%), with a simultaneous upfront surgical approach performed in 84.8%. Most patients underwent bilateral NSS (70.4%). There were no early complications in this series, but 39.4% had clinical complications. The five-year survival rate was 76%. Therefore, it is clear that the surgical approach to BWT plays a crucial role in achieving good outcomes. However, it is difficult to standardize surgical techniques and technology may have the potential to enhance safety.

Efficacy and safety of cryoablation for localized renal tumor as an alternative approach to partial nephrectomy

Introduction

Renal cryoablation displays a profile of high tolerance, including in a frail population. Cryoablation appears as a validated alternative treatment to surgery for renal tumors smaller than 4 cm. However, evidence is lacking for larger tumors, despite encouraging data for tumors up to 7 cm.

Material and methods

This retrospective descriptive study of a population with a stage T1b renal tumor treated by cryoablation was conducted at the Nantes University Hospital between January 2009 and July 2021. Primary endpoint was 3-year rate of local recurrence. Secondary endpoints included technical efficacy, overall and cancer-specific survivals, and safety assessment.

Results

A total of 63 patients were analyzed. Three-year rate of local recurrence was 11.1%. Primary and secondary technical efficacies were achieved in 88.9% and 96.8% of patients, respectively, and 3-year overall and cancer-specific survival were 87.3% and 95.2%, respectively. Most patients (73%) experienced no complications, 13% of patients had minor (CIRSE grades 1 or 2) adverse effects, and 13% had severe but non-lethal (CIRSE grade 3) adverse effects. One patient died following cryoablation due to colic perforation. The most common AE (all grades) was hemorrhage (9.5%).

Discussion

This study showed a good efficacy and safety of cryoablation for renal tumors up to 7 cm (T1b). Our results were consistent with a rather sparse literature and contributed to guide future recommendations about cryoablation as an alternative to surgery for T1b renal tumors.

Renal epithelioid angiomyolipoma: A case report

Epithelioid angiomyolipoma (EAML) of the kidney is an uncommon neoplasm with malignant potential. It can occur sporadically or be associated with tuberous sclerosis. EAML is a monotypic variant of angiomyolipoma (AML), which is classified as neoplasm of the perivascular epithelioid cell or perivascular epithelioid cell tumor. Due to its epithelioid nature and paucity of fat components, unlike classic AML, which has abundant adipose tissue with characteristic features on CT scans, it is difficult to distinguish EAML from renal cell carcinoma and fat-poor AML on CT or MRI preoperatively, which may lead to misdiagnosis and unnecessary nephrectomy. The present report describes two cases of renal EAML, which were successfully treated by laparoscopic surgery. Preoperative diagnosis had not been achieved until surgery was performed and histological analysis was accomplished. No local recurrence or distal metastasis was observed during follow-up. Although the differential diagnosis was challenging preoperatively, a diagnosis of EAML should be considered and surgical excision was the preferred treatment strategy for the patients with localized tumors.

Laparoscopic Radical Nephrectomy with Transperitoneal Approach for Large Renal Tumors: Standardized Surgical Technique and Outcomes

Background: Minimally invasive surgery is used only in selected cases of renal masses greater than 7 cm, and few studies exist in this setting. This study aimed to evaluate the safety and effectiveness of a laparoscopic surgical approach for the treatment of large renal tumors using a standardized technique. Materials and Methods: Data of patients who underwent laparoscopic nephrectomy (LN) using the transperitoneal approach were retrospectively evaluated from December 2019 to September 2022. The study population was divided into two groups: patients with renal masses <7 cm (Group A) and those with renal masses ≥7 cm in diameter (Group B). The intraoperative and postoperative outcomes were compared. Results: Forty patients were enrolled (16 in Group A and 24 in Group B) in this study. Although significant difference in terms of age and American Society of Anesthesiologists score were detected, the two groups did not differ in mean operative time (130 minutes standard deviation [SD] ± 64 versus 148 minutes DS ± 56; P = .376), intraoperative complications (0% versus 8.3%; P = .508), need for postoperative transfusion (12% versus 12%; P > .999), and length of stay (3.38 DS ± 0.62 days versus 3.92 DS ± 2.47; P = .313). One patient had a local recurrence and died ∼13 months after surgery. Furthermore, 2 patients developed trocar-site incisional hernia in Group B. Conclusion: In this cohort of patients, LN for large renal tumors appeared to be safe and feasible. Larger mass dimension does not appear to influence the outcomes when the surgery is performed using a standardized technique by experienced surgeons.

Misdiagnosis of renal pelvic unicentric Castleman disease: a case report

Castleman disease is a rare heterogeneous lymphoproliferative disorder of unknown etiology. Unicentric Castleman disease (UCD) is more common. UCD can occur at any site where lymphatic tissue exists, most commonly in the mediastinum, neck, and abdominal cavity, etc. in the current study, we reported a 46-year-old woman, who has left low back pain and discomfort. Magnetic resonance imaging (MRI) of the kidneys showed the left renal pelvis was occupied, left hydronephrosis, and the left renal hilum and retroperitoneal lymph nodes were enlarged. Enhanced kidney CT showed that the "pelvic tumor" was moderately enhanced in the bottom part in corticomedullary phase, while in nephrogenic phase, it was unevenly enhanced with a highly enhanced bottom part and weakly enhanced upper part. In excretory phase, reinforcement was decreased. "left renal pelvis tumor" was diagnosed and she underwent surgical treatment with left nephrectomy. However, histopathological examination indicated the UCD. We suggest that for renal pelvic tumors having imaging characteristics of homogeneous soft tissue density and heterogeneous CT enhancement, the hyaline vascular type of UCD could be taken into consideration for differential diagnosis.

Potential Role of VHL, PTEN, and BAP1 Mutations in Renal Tumors

The genetic profiling of renal tumors has revealed genomic regions commonly affected by structural changes and a general genetic heterogeneity. The VHL, PTEN, and BAP1 genes are often mutated in renal tumors. The frequency and clinical relevance of these mutations in renal tumors are still being researched. In our study, we investigated VHL, PTEN, and BAP1 genes and the sequencing of 24 samples of patients with renal tumors, revealing that VHL was mutated at a noticeable frequency (25%). Six of the investigated samples showed mutations, and one genetic polymorphism (rs779805) was detected in both heterozygote and homozygote forms. PTEN gene mutation was observed in only one sample, and one specimen showed genetic polymorphism. In the case of the BAP1 gene, all of the samples were wild types. Interestingly, VHL mutation was detected in two female patients diagnosed with AML and in one with oncocytoma. We assume that VHL or PTEN mutations may contribute to the development of human renal cancer. However, the overall mutation rate was low in all specimens investigated, and the development and prognosis of the disease were not exclusively associated with these types of genetic alterations.

Radiofrequency-assisted, laparoscopic, clampless partial nephrectomy in patients with low-complexity small renal tumors: A retrospective cohort study

Background

This single-center, retrospective study was performed to investigate the safety and efficacy of radiofrequency-assisted (RF), laparoscopic partial nephrectomy (PN) with zero ischemia in patients with low-complexity small renal tumors.

Materials and Methods

Patients with small renal masses (SRMs) who underwent laparoscopic, clampless laparoscopic partial nephrectomy - radiofrequency assisted (LPN-RFA) between January 2016 and June 2020 were studied. Demographics, clinical and pathological characteristics, recurrence-free survival, and overall survival were recorded.

Results

Fifty-two SRMs were excised from corresponding patients using RFA-LPN. The median tumor size was 2.5 cm and all specimens involved low-complexity masses according to the renal nephrometry score. No conversions to radical nephrectomy were recorded. Postoperatively, there were one patient with fever, one with hematuria, and two with urinary leakage treated endoscopically. The majority of tumors (48/52, 86.2%) were clear-cell carcinomas. According to the glomerular filtration rate postoperatively and 12 months' posttreatment, adequate renal function was preserved in all patients. There were no positive surgical margins identified postoperatively and no recurrences during a median follow-up 24 months. All patients were alive at the last follow-up.

Conclusions

This study suggests that RFA laparoscopic clampless PN represents an effective method for managing patients with low-complexity SRMs. It offers adequate intraoperative safety and excellent mid-term oncological control and functional preservation.

Comparison of laparoscopic partial nephrectomy performed with AirSeal® system vs. standard insufflator: results from a referral center

Objective

To compare perioperative and oncologic surgical outcomes during laparoscopic partial nephrectomy (LPN) performed by standard carbon dioxide insufflation, with those from surgeries in which the AirSeal® intelligent insufflation system was used for renal tumors.

Materials and methods

A total of 27 patients with renal tumor were identified, 14 underwent LPN with AirSeal® (group A) and 13 LPN with standard insufflator (group B), respectively. Demographic baseline characteristics were similar in the two groups.

Results

The size of the tumor was largest in group B (29.64 vs. 32.1 mm). The mean operative time was shorter in the AirSeal® group [group A: mean 109.0 min, median 107.5 min, interquartile range (IQR) 85; group B: mean 121.0 min, median 120.0 min, IQR 50.0]. Positive margin rates were absent in the two groups. Estimated blood loss presented a difference in the perioperative period (group A: mean 1.5 g/dL, median 1.45 g/dL; group B: mean 2.15 g/dL, median 2.2 g/dL). Time to ischemia was found to be shorter in group A with a median of 18 min compared to a median of 20 min in group B. No subcutaneous emphysema, pneumothorax, and pneumomediastinum cases occurred in either group. A postoperative complication developed in one patient requiring superselective embolization.

Conclusion

In selected patients, our preliminary surgical experience has shown that the LPN procedure performed with the aid of the AirSeal® intelligent insufflation system can be used to treat even medium-/high-complexity kidney lesions, with a reduction in operating times, lower rates of complications, and perioperative blood loss.

Clinical trial registration

AirSealV1.

Cardiovascular surgical experiences of IVC tumor and thrombus: Operative strategies Based on 51 consecutive patients

BACKGROUND

The only beneficial treatment option for the management of inferior vena cava (IVC) tumor thrombus is complete tumor removal. The aim of this study was to report our experience in surgical and clinical outcomes in patients with tumor thrombosis in IVC.

METHODS

A retrospective chart review of patients who underwent surgical resection of IVC tumor at our institution over the past 10 years was performed. The patients were identified using a prospectively maintained database.

RESULTS

We identified 51 patients, the mean age was 53.4 ± 16.8 years, and 25.4% were female. They were divided into three groups based on tumor thrombosis level. Twenty patients (39.2%) required sternotomy, and cardiopulmonary bypass (CPB) was used in 19 (37.2%) patients, and 2 (3.9%) cases underwent coronary artery bypass graft. The perioperative complications were severe bleeding (3 patients), pulmonary embolism (2 patients), and duodenal perforation (1 patient). Three (5.8%) in-hospital deaths occurred, and all were due to severe abdominal bleeding. After a mean follow-up time of 46.5 ± 42.0 months, 29 (56.9%) patients were alive. The mean survival time was 75.2 ± 8.4 months. In multivariate analysis, higher age (p = 0.033) and male gender (p = 0.033) proved to be independent prognostic factors.

CONCLUSIONS

Tumor thrombus extending to the IVC is a rare and challenging event. Although using CPB may be safe and result in long-term survival with acceptable function, excessive bleeding during surgery may limit the use of this method.

Laparoscopic and Open Nephron-Sparing Surgery for Radius Exophytic/Endophytic Nearness Anterior/ Posterior Location Nephrometry Score 7 and Higher Kidney Tumors: A Comparison of Oncological and Functional Outcomes Using the Pentafecta Score

OBJECTIVE

This study aimed to evaluate oncological and functional outcomes of nephron- sparing surgery by comparing open and laparoscopic approaches in a consecutive series of patients with intermediate and high complexity renal masses.

MATERIALS AND METHODS

We retrospectively reviewed all nephron-sparing surgery cases in 2 referral centers from January 2013 to January 2020. Tumor complexity was graded according to radius exophytic/endophytic nearness anterior/posterior location nephrometry score. Patients with a single kidney tumor with a radius exophytic/endophytic nearness anterior/posterior location score ≥ 7 were evaluated. Exclusion criteria were solitary kidney, multiple/bilateral tumors, and a low radius exophytic/endophytic nearness Anterior/Posterior location score (<7). Patients were divided according to the surgical approach: the laparoscopic tumor enucleation and the open wedge resection groups. The Trifecta and Pentafecta score achievement rates were assessed.

RESULTS

Two hundred thirteen patients were included in the analysis, 76 in laparoscopic tumor enucleation group and 137 in the open wedge resection group. There were no statistically significant differences in preoperative data between laparoscopic tumor enucleation and open wedge resection groups, except for the higher percentage of T1a masses in the latter group. The mean 24-hour blood loss and length of stay were higher in the open wedge resection group. Minor and major postoperative complication rates were comparable. No significant difference in terms of the Trifecta score was reported. Pentafecta score was achieved in 35/76 (46.1%) and 61/137 (44.5%) cases in the laparoscopic tumor enucleation and open wedge resection groups, respectively.

CONCLUSION

Our study showed that laparoscopic tumor enucleation was associated with significantly lower blood and length of stay. Postoperative complications and the achievement of the Pentafecta score were similar in both surgical approaches.

Pediatric Primary Yolk Sac Tumour of the Kidney: Recommendations for Pretreatment Diagnosis

Introduction Although nephroblastomas are frequently treated without prior biopsy, there are the occasional other pediatric renal tumors that require different management. In the literature, there are around 30 primary renal germ cell tumors (GCT), including four cases of Yolk sac tumor (YST). We present another primary renal YST.Case report: A five-year-old boy was diagnosed as Wilms tumor on radiology and needle biopsy. He received chemotherapy, with no response. The post-chemotherapy resection specimen revealed a YST.Conclusion: Renal YST may be indistinguishable from Wilms tumor clinically and radiologically. For pre-biopsy chemotherapy management protocols, serum tumor markers such as AFP may be recommended to identify the occasional GCT, including YST. Pre-chemotherapy needle biopsies may lead to misdiagnosis, and may require confirmation by an experienced pathologist or central review.

Diagnostic Value of Multi-Mode Ultrasonic Flow Imaging Examination in Solid Renal Tumors of Different Sizes

Purposes: To explore the value of Microflow Imaging (MFI) in renal solid tumors. Methods: A total of 195 patients with 199 lesions pathologically confirmed masses were retrospectively analyzed. The 199 masses were divided into the tumor ≤ 4 cm group (n = 104) and tumor > 4 cm group (n = 95). The diagnostic efficacy of Color Doppler Flow Imaging (CDFI), Power Doppler Imaging (PDI) and MFI in renal tumors sizes were compared by determining the Adler grade, vascular morphology and peripheral blood flow. Results: Among 199 tumors, 161 lesions were malignant and 38 lesions were benign. MFI in malignant tumor ≤ 4 cm demonstrated statistically significant differences in Adler grade and vascular morphology as compared to CDFI and PDI (p < 0.05). In malignant tumor > 4 cm group, MFI showed significant difference in vascular morphology compared with CDFI (p < 0.05). MFI showed a significant difference in the peripheral annular blood flow of malignant tumors when compared to CDFI and PDI (p < 0.05). In addition, the malignant tumors of the two sizes by MFI in peripheral annular blood flow detection showed significant difference (p < 0.05). The area under the curve of ROC by MFI in the tumor ≤ 4 cm was 0.771, which was higher than CDFI and PDI (p < 0.05), but no obvious difference among the tumor > 4 cm (p > 0.05). Conclusion: MFI provides a new method for the differential diagnosis of small renal carcinoma. Based on the convenience and non-radiation of MFI, we can choose MFI as an imaging diagnostic tool for patients who need long-term active surveillance (AS) follow-up.

Cone Beam Computed Tomography Image Fusion with Cross Sectional Images for Percutaneous Renal Tumor Ablation: Preliminary Data

PURPOSE

Percutaneous ablative treatments in the kidney are now standard options for local cancer therapy. Multimodality image guidance, combining two 3D image sets, may improve procedural images and interventional strategies. We aimed to assess the value of intra-procedural cone beam computed tomography (CBCT) with magnetic resonance (MR) or CT imaging fusion technique in the guidance of percutaneous microwave ablation (MWA) of renal neoplasms.

MATERIALS AND METHODS

Fifteen patients (eight males, seven females, median age 65 years, median lesion size 20 mm) underwent percutaneous MWA for 15 renal tumors. All the procedures were performed in a dedicated angiography room setting; CBCT ablation planning capabilities included multimodality image fusion. Preoperative contrast-enhanced CT was available in 12 patients, whereas magnetic resonance imaging in the remaining. All patients were considered inoperable due to comorbidities, advanced age, and/or refusal to undergo surgery. Exclusion criteria were: tumors visible at unenhanced CBCT, metastatic disease, and uncorrected coagulopathy. Technical success and technical effectiveness were calculated. Procedural time, complications and recurrences were registered.

RESULTS

MWA under CBCT-guidance with fusion technique was technically successful in 14 out of 15 cases (93%). The median procedural time was 45 min. No procedure-related complications were reported. No enhancing tissue was visualized in the area of ablation at 1-month follow-up. All 15 cases were recurrence-free at last follow-up assessment (median follow-up of 12 months); no cancer-specific deaths were registered.

CONCLUSION

CBCT-CT/MR image fusion is technically feasible and safe in achieving correct targeting and complete ablation of renal lesions. This approach bears the potential to overcome most of the limitations of unenhanced CBCT guidance alone; larger series are needed to validate this technique.

Whole-Lesion CT Texture Analysis as a Quantitative Biomarker for the Identification of Homogeneous Renal Tumors

Renal tumors are very common in the urinary system, and the preoperative differential diagnosis of homogeneous renal tumors remains a challenge. This study aimed to evaluate the feasibility of the whole-lesion CT texture analysis for the identification of homogeneous renal tumors including clear cell renal cell carcinoma (ccRCC), chromophobe RCC (chRCC), and renal oncocytoma (RO). This retrospective study was approved by our local IRB. Contrast-enhanced CT examination was performed in 128 patients and histopathologically confirmed ccRCC, chRCC, and RO. The one-way ANOVA test with Bonferroni corrections was used to compare the differences, and the receiver operating characteristic (ROC) curve analysis was applied to determine the diagnostic efficiency. The whole-lesion CT histogram analysis was used to demonstrate significant differences between ccRCC and chRCC in both arterial and venous phases, and the entropy demonstrated excellent performance in discriminating these two types of tumors (AUCs = 0.95, 0.91). The inhomogeneity of ccRCC was significantly higher than that of RO both in arterial and venous phases. The entropy of chRCC was significantly lower than that of RO, and the kurtosis and entropy yielded high sensitivity (91%) and moderate specificity (74%) in the arterial phase. The whole-lesion CT histogram analysis could be useful for the differential diagnosis of homogeneous ccRCC, chRCC, and RO.

Renal Mass Found on Imaging of Spine for Back Pain: An Incidental Finding

A middle-aged female patient who presented with back pain was found incidentally to have a renal mass by magnetic resonance imaging (MRI). Further imaging, including computerized tomography (CT) with contrast, suggested a high likelihood of malignancy. Following surgical resection, the tumor was found to be a rare benign lesion on subsequent pathological examination. The patient had conservative treatment for her presenting spine issues and is doing very well. Prompt work-up and treatment of incidental findings by the team of primary care, physical medicine and rehabilitation physicians, radiologists, pathologists, and surgeons helped to ensure a good outcome. Residents had a learning opportunity about the disease and on timely management of incidental findings.

An Evaluation of a Web-Based Decision Aid for Treatment Planning of Small Kidney Tumors: Pilot Randomized Controlled Trial

Background

Surgery is the most common treatment for localized small kidney masses (SKMs) up to 4 cm, despite a lack of evidence for improved overall survival. Nonsurgical management options are gaining recognition, as evidence supports the indolence of most SKMs. Decision aids (DAs) have been shown to improve patient comprehension of the trade-offs of treatment options and overall decision quality, and may improve consideration of all major options according to individual health priorities and preferences.

Objective

This pilot randomized controlled trial (RCT) primarily aims to evaluate the impact of a new web-based DA on treatment decisions for patients with SKM; that is, selection of surgical versus nonsurgical treatment options. Secondary objectives include an assessment of decision-making outcomes: decisional conflict, decision satisfaction, and an understanding of individual preferences for treatment that incorporate the trade-offs associated with surgical versus nonsurgical interventions.

Methods

Three phases comprise the construction and evaluation of a new web-based DA on SKM treatment. In phase 1, this DA was developed in print format through a multidisciplinary design committee incorporating patient focus groups. Phase 2 was an observational study on patient knowledge and decision-making measures after randomization to receive the printed DA or institutional educational materials, which identified further educational needs applied to a web-based DA. Phase 3 will preliminarily evaluate the web-based DA: in a pilot RCT, 50 adults diagnosed with SKMs will receive the web-based DA or an existing web-based institutional website at urology clinics at a large academic medical center. The web-based DA applies risk communication and information about diagnosis and treatment options, elicits preferences regarding treatment options, and provides a set of options to consider with their doctor based on a decision-analytic model of benefits/harm analysis that accounts for comorbidity, age group, and tumor features. Questionnaires and treatment decision data will be gathered before and after viewing the educational material.

Results

This phase will consist of a pilot RCT from August 2022 to January 2023 to establish feasibility and preliminarily evaluate decision outcomes. Previous study phases from 2018 to 2020 supported the feasibility of providing the printed DA in urology clinics before clinical consultation and demonstrated increased patient knowledge about the diagnosis and treatment options and greater likelihood of favoring nonsurgical treatment just before consultation. This study was funded by the National Cancer Institute. Recruitment will begin in August 2022.

Conclusions

A web-based DA has been designed to address educational needs for patients making treatment decisions for SKM, accounting for comorbidities and treatment-related benefits and risks. Outcomes from the pilot trial will evaluate the potential of a web-based DA in personalizing treatment decisions and in helping patients weigh attributes of surgical versus nonsurgical treatment options for their SKMs.

Trial Registration

ClinicalTrials.gov NCT05387863; https://clinicaltrials.gov/ct2/show/NCT05387863

International Registered Report Identifier (IRRID)

PRR1-10.2196/41451

Clinical implications of 3D printing technology in preoperative evaluation of partial nephrectomy

OBJECTIVES

Renal cancer is a common malignancy of the urinary system, and the partial nephrectomy is a common surgical modality for early renal cancer. 3D printing technology can create a visual three-dimensional model by using 3D digital models of the patient's imaging data. With this model, surgeons can perform preoperative assessment to clarify the location, depth, and blood supply of the tumor, which helps to develop preoperative plans and achieve better surgical outcomes. In this study, the R.E.N.A.L scoring system was used to stratify patients with renal tumors and to explore the clinical application value of 3D printing technology in laparoscopic partial nephrectomy.

METHODS

A total of 114 renal cancer patients who received laparoscopic partial nephrectomy in Xiangya Hospital from June 2019 to December 2020 were enrolled. The patients were assigned into an experimental group (n=52) and a control group (n=62) according to whether 3D printing technology was performed, and the differences in perioperative parameters between the 2 groups were compared. Thirty-nine patients were assigned into a low-complexity group (4-6 points), 32 into a moderate-complexity group (7-9 points), and 43 into a high-complexity group (10-12 points) according to R.E.N.A.L score, and the differences in perioperative parameters between the experimental group and the control group in each score group were compared.

RESULTS

The experimental group had shorter operative time, renal ischemia time, and postoperative hospital stay (all P<0.05), less intraoperative blood loss (P=0.047), and smaller postoperative blood creatinine change (P=0.032) compared with the control group. In the low-complexity group, there were no statistically significant differences between the experimental group and the control group in operation time, renal ischemia time, intraoperative blood loss, postoperative blood creatinine changes, and postoperative hospital stay (all P>0.05). In the moderate- and high- complexity groups, the experimental group had shorter operative time, renal ischemia time, and postoperative hospital stay (P<0.05 or P<0.001), less intraoperative blood loss (P=0.022 and P<0.001, respectively), and smaller postoperative blood creatinine changes (P<0.05 and P<0.001, respectively) compared with the control group.

CONCLUSIONS

Compared with renal tumor patients with R.E.N.A.L score<7, renal cancer patients with R.E.N.A.L score≥7 may benefit more from 3D printing assessment before undergoing partial nephrectomy.

Predictors of Positive Surgical Margins after Robot-Assisted Partial Nephrectomy for Localized Renal Tumors: Insights from a Large Multicenter International Prospective Observational Project (The Surface-Intermediate-Base Margin Score Consortium)

Background: To explore predictors of positive surgical margins (PSM) after robotic partial nephrectomy (PN) in a large multicenter international observational project, harnessing the Surface-Intermediate-Base (SIB) margin score to report the resection technique after PN in a standardized way. Methods: Data from consecutive patients with cT1-2N0M0 renal masses treated with PN from September 2014 to March 2015 at 16 tertiary referral centers and included in the SIB margin score International Consortium were prospectively collected. For the present study, only patients treated with robotic PN were included. Uni- and multivariable analysis were fitted to explore clinical and surgical predictors of PSMs after PN. Results: Overall, 289 patients were enrolled. Median (IQR) preoperative tumor size was 3.0 (2.3−4.2) cm and median (IQR) PADUA score was 8 (7−9). SIB scores of 0−2 (enucleation), 3−4 (enucleoresection) and 5 (resection) were reported in 53.3%, 27.3% and 19.4% of cases, respectively. A PSM was recorded in 18 (6.2%) patients. PSM rate was 4.5%, 11.4% and 3.6% in case of enucleation, enucleoresection and resection, respectively. Patients with PSMs had tumors with a higher rate of contact with the urinary collecting system (55.6% vs. 27.3%; p < 0.001) and a longer median warm ischemia time (22 vs. 16 min; p = 0.02) compared with patients with negative surgical margins, while no differences emerged between the two groups in terms of other tumor features (i.e., pathological diameter, PADUA score). In multivariable analysis, only enucleoresection (SIB score 3−4) versus enucleation (SIB score 0−2) was found to be an independent predictor of PSM at final pathology (HR: 2.68; 95% CI: 1.25−7.63; p = 0.04), while resection (SIB score 5) was not. Conclusions: In our experience, enucleoresection led to a higher risk of PSMs as compared to enucleation. Further studies are needed to assess the differential impacts of resection technique and surgeon’s experience on margin status after robotic PN.

Clampless Laparoscopic Tumor Enucleation for Exophytic Masses Greater Than 4 cm: Is Renorrhaphy Necessary?

Objective: To demonstrate the safety of clampless 3D laparoscopic tumor enucleation (cLTE) for exophytic T1b kidney masses, avoiding suture to achieve hemostasis. Methods: Between January 2010 and January 2021, 241 consecutive patients with an exophytic renal tumor underwent sutureless cLTE. Patients with predominantly endophytic growth or tumors 4 mm closer to the collecting system less were excluded. In all cases, an attempt was made to accomplish surgery without suturing kidney parenchyma. Data were obtained from a retrospective review of history and physical examinations, operative and pathology reports, anesthesia records during the hospital stay, and follow-up visits. Results: Among 241 patients who underwent cLTE, 148 had cT1a and 93 had cT1b renal tumor. The median tumor size was 32 mm, and the median R.E.N.A.L. (radius exophytic/endophytic nearness anterior/posterior location) score was 6. Renorrhaphy was necessary in 5 cases. The median operative time (OT) was 100 minutes, and the estimated blood loss (EBL) was 150 mL. The median 24-hour decrease in hemoglobin was 1.8 g/dL. The median length of stay was 4 days. Nineteen patients had postoperative complications: 3 cases had Clavien-Dindo (CD) 3a or more, 6 had CD2, and 10 had CD1. Comparing the T1a and T1b groups, except for the median OT and the EBL, no significant differences were observed in all the other variables analyzed. In both groups, renal function was preserved after 1 year from surgery. Conclusion: Our experience showed that sutureless cLTE is safe and feasible for T1b tumors leading to radical oncological outcomes and preserving renal function.

Initial experience of robot-assisted radical nephrectomy in Japan: Single institutional study of 12 cases

INTRODUCTION

To evaluate the initial experience of robot-assisted radical nephrectomy (RARN) in a single institution in Japan.

METHODS

This study included a total of 12 patients with renal tumors who were not preoperatively regarded as optimal candidates for robot-assisted partial nephrectomy (RAPN) and subsequently treated with RARN between April 2019 and June 2021 at our institution. Comprehensive perioperative outcomes in these patients were retrospectively analyzed.

RESULTS

Of the 12 included patients, 10 and two were male and female, respectively, and the median age was 66 years. The median tumor diameter was 44 mm, and four, four and four patients were classified into cT1a, cT1b and cT3a, respectively. There was no patient requiring open conversion, and the median operative and console times were 167 and 79 minutes, respectively. The median estimated blood loss was 42 cc, and no patient required blood transfusion. During the perioperative period, no major complication corresponding to Clavien-Dindo grade ≥3 occurred. Nine, two and one patient were pathologically diagnosed with clear cell carcinoma (CCC), non-CCC and benign cyst, respectively, and there was no patient who developed recurrent diseases.

CONCLUSIONS

Considering complicated tumor characteristics not amenable to RAPN in this series, such as an intravenous tumor thrombus or previous history of open partial nephrectomy, perioperative outcomes of initial experience with RARN in Japan could be considered favorable. Collectively, these findings suggest that RARN may be a promising alternative to laparoscopic radical nephrectomy for patients with complicated renal tumors, contraindicated for RAPN.

Bilateral Renal Tumors in Children: The First 5 Years' Experience of National Centralization in The Netherlands and a Narrative Review of the Literature

Survival of unilateral Wilms tumors (WTs) is exceeding 90%, whereas bilateral WTs have an inferior outcome. We evaluated all Dutch patients with bilateral kidney tumors, treated in the first five years of national centralization and reviewed relevant literature. We identified 24 patients in our center (2015–2020), 23 patients had WT/nephroblastomatosis and one renal cell carcinoma. Patients were treated according to SIOP-RTSG protocols. Chemotherapy response was observed in 26/34 WTs. Nephroblastomatosis lesions were stable (n = 7) or showed response (n = 18). Nephron-sparing surgery was performed in 11/22 patients undergoing surgery (n = 2 kidneys positive margins). Local stage in 20 patients with ≥1 WT revealed stage I (n = 7), II (n = 4) and III (n = 9). Histology was intermediate risk in 15 patients and high risk in 5. Three patients developed a WT in a treated nephroblastomatosis lesion. Two of 24 patients died following toxicity and renal failure, i.e., respectively dialysis-related invasive fungal infection and septic shock. Genetic predisposition was confirmed in 18/24 patients. Our literature review revealed that knowledge is scarce on bilateral renal tumor patients with metastases and that radiotherapy seems important for local stage III patients. Bilateral renal tumors are a therapeutic challenge. We describe management and outcome in a national expert center and summarized available literature, serving as baseline for further improvement of care.

Low Lymphocyte-to-Monocyte Ratio Is the Potential Indicator of Worse Overall Survival in Patients with Renal Cell Carcinoma and Venous Tumor Thrombus

The purpose of the study was to determine the influence of lymphocyte-to-monocyte ratio (LMR), platelet-to-lymphocyte ratio (PLR), and neutrophil-to-lymphocyte ratio (NLR) values on the prognosis in patients with renal cell carcinoma (RCC) and venous tumor thrombus. The respective data of 91 patients treated with radical surgery in the years 2012-2021 in 2 tertiary referral urological centers were retrieved from local medical databases. Mean calculated 3-year overall survival (OS) reached 70% (mean follow-up 35.3 months). The association between lower LMR and the presence of tumor necrosis (p = 0.0004) was observed. Amongst systemic inflammatory markers, only LMR was selected as the sensitive marker predicting death with a calculated cut-off value of 2.53. OS was decreased in patients presenting with low LMR when compared to the high LMR group (39% vs. 82%, p = 0.0011). Neither NLR nor PLR were associated with survival rates. In multivariate analysis, LMR was identified as the independent prognostic factor (HR = 0.20, 95% CI 0.07-0.55, p = 0.001). Low values of LMR (<2.53) are independently connected with poorer OS in patients with RCC and coexisting tumor thrombus. The incorporation of the hematological variables into the prognostic model greatly increased its accuracy in predicting survival in the distinctive subpopulation of patients with RCC.

Perioperative management including dual cell salvage in a Jehovah's Witness patient undergoing major urological surgery

Complex surgery associated with major hemorrhage presents particular risks for Jehovah's Witnesses who do not accept transfusion of blood products. Intraoperative use of two cell saver machines simultaneously can maximize the yield of salvaged blood from both the operative field and from washed surgical swabs and can potentially be life-saving.

Differentiating Benign from Malignant Renal Tumors Using T2- and Diffusion-Weighted Images: A Comparison of Deep Learning and Radiomics Models Versus Assessment from Radiologists

BACKGROUND

Differentiating benign from malignant renal tumors is important for selection of the most effective treatment.

PURPOSE

To develop magnetic resonance imaging (MRI)-based deep learning (DL) models for differentiation of benign and malignant renal tumors and to compare their discrimination performance with the performance of radiomics models and assessment by radiologists.

STUDY TYPE

Retrospective.

POPULATION

A total of 217 patients were randomly assigned to a training cohort (N = 173) or a testing cohort (N = 44).

FIELD STRENGTH/SEQUENCE

Diffusion-weighted imaging (DWI) and fast spin-echo sequence T2-weighted imaging (T2WI) at 3.0T.

ASSESSMENT

A radiologist manually labeled the region of interest (ROI) on each image. Three DL models using ResNet-18 architecture and three radiomics models using random forest were developed using T2WI alone, DWI alone, and a combination of the two image sets to discriminate between benign and malignant renal tumors. The diagnostic performance of two radiologists was assessed based on professional experience. We also compared the performance of each model and the radiologists.

STATISTICAL TESTS

The area under the receiver operating characteristic (ROC) curve (AUC) was used to assess the performance of each model and the radiologists. P < 0.05 indicated statistical significance.

RESULTS

The AUC of the DL models based on T2WI, DWI, and the combination was 0.906, 0.846, and 0.925 in the testing cohorts, respectively. The AUC of the combination DL model was significantly better than that of the models based on individual sequences (0.925 > 0.906, 0.925 > 0.846). The AUC of the radiomics models based on T2WI, DWI, and the combination was 0.824, 0.742, and 0.826 in the testing cohorts, respectively. The AUC of two radiologists was 0.724 and 0.667 in the testing cohorts.

CONCLUSION

Thus, the MRI-based DL model is useful for differentiating benign from malignant renal tumors in clinic, and the DL model based on T2WI + DWI had the best performance.

LEVEL OF EVIDENCE

3 TECHNICAL EFFICACY STAGE: 2.

MRI Characteristics of Pediatric Renal Tumors: A SIOP-RTSG Radiology Panel Delphi Study

BACKGROUND

The SIOP-Renal Tumor Study Group (RTSG) does not advocate invasive procedures to determine histology before the start of therapy. This may induce misdiagnosis-based treatment initiation, but only for a relatively small percentage of approximately 10% of non-Wilms tumors (non-WTs). MRI could be useful for reducing misdiagnosis, but there is no global consensus on differentiating characteristics.

PURPOSE

To identify MRI characteristics that may be used for discrimination of newly diagnosed pediatric renal tumors.

STUDY TYPE

Consensus process using a Delphi method.

POPULATION

Not applicable.

FIELD STRENGTH/SEQUENCE

Abdominal MRI including T1- and T2-weighted imaging, contrast-enhanced MRI, and diffusion-weighted imaging at 1.5 or 3 T.

ASSESSMENT

Twenty-three radiologists from the SIOP-RTSG radiology panel with ≥5 years of experience in MRI of pediatric renal tumors and/or who had assessed ≥50 MRI scans of pediatric renal tumors in the past 5 years identified potentially discriminatory characteristics in the first questionnaire. These characteristics were scored in the subsequent second round, consisting of 5-point Likert scales, ranking- and multiple choice questions.

STATISTICAL TESTS

The cut-off value for consensus and agreement among the majority was ≥75% and ≥60%, respectively, with a median of ≥4 on the Likert scale.

RESULTS

Consensus on specific characteristics mainly concerned the discrimination between WTs and non-WTs, and WTs and nephrogenic rest(s) (NR)/nephroblastomatosis. The presence of bilateral lesions (75.0%) and NR/nephroblastomatosis (65.0%) were MRI characteristics indicated as specific for the diagnosis of a WT, and 91.3% of the participants agreed that MRI is useful to distinguish NR/nephroblastomatosis from WT. Furthermore, all participants agreed that age influenced their prediction in the discrimination of pediatric renal tumors.

DATA CONCLUSION

Although the discrimination of pediatric renal tumors based on MRI remains challenging, this study identified some specific characteristics for tumor subtypes, based on the shared opinion of experts. These results may guide future validation studies and innovative efforts.

LEVEL OF EVIDENCE

3 Technical Efficacy Stage: 3.

The efficacy evaluation of partial nephrectomy with selective renal artery branch occlusion by laparoscopy

BACKGROUND

To investigate the clinical application and effect of laparoscopic partial nephrectomy with renal artery branch occlusion in the treatment of early renal tumors.

METHODS

A retrospective analysis was conducted on the clinical data of 15 cases of renal tumor patients who underwent partial nephrectomy by laparoscopic selective renal artery branch occlusion in our department from January 2017 to January 2018. Nine male patients and 6 female patients were aged 46 to 65 years, with an average age of 54.3 ± 7.2 years. The diameters of tumors were 2.2 to 4.0 cm, with an average of 3.3 ± 0.7 cm. There are 10 tumors locating on the left side and 5 on the right side. Preoperative renal glomerular filtration rate (GFR) were 77.3 to 61.9 mL/min with an average of 47.6 ± 7.5 mL/min. All patients' diseased kidneys underwent renal computer tomography angiography examination before surgery. And the diseased kidney underwent reexamination of renal GFR. The operation time, renal artery branch occlusion time, intraoperative blood loss, postoperative hospital stay, changes of renal function, and complications were evaluated.

RESULTS

All surgery were completed successfully, the surgery time was 136.7 ± 15.2 min, intraoperative renal artery branch occlusion time was 21.3 ± 4.5 min, the intraoperative blood loss was 223.3 ± 69.5 mL, the postoperative hospital stay was 6.5 ± 1.7 days, and the postoperative 1-month GFR was 49.5 ± 6.6 mL/min. There was no significant difference between the renal GFR before and after surgery (P > .05). There was no blood transfusion and transfer open surgery cases. The patients were followed up for 3 to 15 months without complications.

CONCLUSIONS

Partial nephrectomy with selective renal artery branch occlusion by laparoscopy is a safe, feasible, and effective method for the treatment of early renal cancer. It makes good use of the technical advantages of clear operation field and fine operation of laparoscopic surgery, avoids the heat ischemia process of the whole kidney, and can better protect the renal function.

Oncological Outcomes of Patients With Different Pathological Features of pT3a Renal Tumor: A Systematic Review and Quantitative Synthesis

Purpose

To identify the differences in oncological outcomes for patients with different pT3a renal tumor invasion patterns and pathological features.

Methods

The protocol of this study was registered on PROSPERO (CRD42021234475). Relevant studies were identified by searching the PubMed, Cochrane library, Embase, and Web of Science databases. Cancer-specific survival (CSS) was selected as the endpoint. Pooled hazard ratio (HR) and 95% confidence interval (CI) extracted from multivariate Cox models were evaluated to identify the hazard association.

Results

A total of 22 studies, which enrolled 12384 patients were included for quantitative synthesis. Sinus fat invasion (SFI) + perinephric fat invasion (PFI) was associated with inferior CSS compared to SFI only (p = 0.02). Comparable CSS was observed between SFI and PFI (p = 0.57). SFI ± PFI showed inferior CSS compared to PFI only (p = 0.0002). The presence of pelvicalyceal system invasion significantly increased the risk of cancer-specific mortality (p = 0.0005). Renal vein invasion (RVI) indicated poor oncological outcomes in terms of CSS (p = 0.002). The concomitant RVI and fat invasion (FI) significantly increased the risk of deterioration of CSS compared to RVI or FI (p < 0.0001). Multiple invasion patterns translated into a significantly decreased CSS (p < 0.0001). Aggressive tumor behavior, including lymph node involvement (p = 0.006), distant metastases (p < 0.00001), sarcomatoid differentiation (p < 0.0001), necrosis (p < 0.0001), Fuhrman grade III or IV (p < 0.0001), positive margin (p < 0.0001), and tumor size >7cm (p < 0.0001) were the predictors of inferior CSS. The lymphovascular invasion (p = 0.67) was indolent in terms of CSS.

Conclusion

This study confirmed the heterogenicity of pT3a renal tumors. Multiple invasion patterns could translate into a significantly decreased CSS, and SFI should not be merged in the SFI + PFI group. The presence of PSI or RVI could significantly increase the risk of cancer-specific mortality. Lymph node involvement, distant metastases, sarcomatoid differentiation, necrosis, high Fuhrman grade, positive margin, and size >7cm were the predictors of inferior CSS. A precise-risk grade of CSS for different invasion patterns including comprehensive combinations may be useful for the further refinements of the TNM system.

Systematic Review Registration

The current study was registered on PROSPERO, and the registration numbers is CRD42021234475.

[Unilateral combined lap partial nephrectomy and pyelolithotomy for ipsilateral tumor & kidney staghorn stone]

OBJECTIVE

To discuss the feasibility, safety, and effectiveness of conventional laparoscopic partial nephrectomy combined with pyelolithotomy for patients with ipsilateral renal tumor and staghorn kidney stone.

MATERIALS AND METHODS

Retrospective multicentral comparative study. Group "Combo" was presented by patients with the mentioned combined pathology (n=15). Group "Standart" (n=69) formed from common patients who underwent standard lap partial nephrectomy for renal tumor in the absence of kidney stones. Perioperative factors and results were studied and compared. Video presentation of combined surgical technique is available at: https://youtu.be/fAfYJDvGzsU.

RESULTS

Of all patients, no positive margins, no conversions to open surgery or nephrectomy & any complications Clavien >III were detected. There were no any significant differences between the two groups except for OR time (150 [120; 210] vs 130 [100; 180] min; p=0,001). Differences between indexes of WIT (16,27+/-3,8 vs 15,9+/-4,5 min; p=0,107), EBL (200 [150; 300] vs 200 [150; 300] cc; p=0,981), length of stay (7 [6;9] vs 8[6;9] days; p=0,611), intraop complications (0,00 vs 4,3%; p=0,411) and values of postop Clavien III rate (0,00 vs 4,3%; p=0,411) for "Combo" & "Standart" respectively were comparable as well as oncological outcomes. Stone-free rate for combined procedures reached 93,3%.

CONCLUSION

conventional laparoscopic partial nephrectomy combined with pyelolithotomy for patients with ipsilateral renal tumor and staghorn kidney stone is safe and efficient alternative to 2-step treatment of this rare disease.

The Influence of Prior Abdominal Surgery on Robot-Assisted Partial Nephrectomy

Background

We evaluated the influence of prior abdominal surgery on perioperative outcomes in patients who underwent robot-assisted partial nephrectomy in initial Japanese series.

Methods

We reviewed patients with small renal tumors who underwent robot-assisted partial nephrectomy from October 2011 to September 2020 at our institution. Patients with prior abdominal surgery were compared with those without prior surgery based on perioperative outcomes. The chi-square test and Mann-Whitney U test were used for statistical analyses of variables.

Results

Of 156 patients who underwent robot-assisted partial nephrectomy, 90 (58%) had no prior abdominal surgery, whereas 66 patients (42%) underwent prior abdominal surgery. No significant differences in perioperative outcomes were observed between with and without prior abdominal surgery groups. In transperitoneal approach robot-assisted partial nephrectomy, 31 patients (80.4%) had prior abdominal surgery. Trocar insertion time in the with prior abdominal surgery group took longer than the without prior abdominal surgery group (32 vs. 28.5 min, P = 0.031). No significant difference was observed in the conversion rate between the two groups (P = 0.556).

Conclusion

Robot-assisted partial nephrectomy appears to be a safe approach for patients with prior abdominal surgery. In transperitoneal approach robot-assisted partial nephrectomy with prior abdominal surgery, trocar insertion time was longer, but no significant differences were found in other outcomes. Transperitoneal approach robot-assisted partial nephrectomy is thus considered a safe procedure for patients with prior abdominal surgery.

[Unilateral combination of staghorn stone with kidney tumor]

This manuscript provides an overview of the available literature about unilateral combination of nephrolithiasis and renal tumor. Analysis of publications has shown that ipsilateral staghorn calculus and kidney tumors are an extremely rare combination. The majority of these infrequent papers describe case reports where the method of treating such patients is limited by the capabilities and competence of the surgeon or clinic. Despite some messages of favorable outcomes of combined interventions, the effectiveness of simultaneous laparoscopic partial nephrectomy and pyelolithotomy has not been studied, and the technique of this procedure, tactics and criteria for choosing this method are not defined.

Application of low-dose CT to the creation of 3D-printed kidney and perinephric tissue models for laparoscopic nephrectomy

PURPOSE

The aim of this study was to explore the feasibility of 3D printing of kidney and perinephric fat based on low-dose CT technology.

PATIENTS AND METHODS

A total of 184 patients with stage T1 complex renal tumors who underwent laparoscopic nephrectomy were prospectively enrolled and divided into three groups: group A (conventional dose kidney and perinephric fat 3D printing group, n = 62), group B (low-dose kidney and perinephric fat 3D printing, n = 64), and group C (conventional dose merely kidney 3D printing group, n = 58). The effective dose (ED), signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were determined. The 3D printing quality was evaluated using a 4-point scale, and interobserver agreement was assessed using the intraclass correlation coefficient (ICC).

RESULTS

The ED of group B was lower than that of group A, with a decrease of 55.1%. The subjective scores of 3D printing quality in all groups were 3 or 4 points. The interobserver agreement among the three observers in 3D printing quality was good (ICC = 0.84-0.92). The perioperative indexes showed that operation time (OT), warm ischemia time (WIT), estimated blood loss (EBL), and laparoscopic partial nephrectomy (LPN) conversion to laparoscopic radical nephrectomy (LRN) in groups A or B were significantly less than those in group C. LPN was more frequent in group A and group B than in group C (all p < 0.017). There were no significant differences in perioperative indexes between group A and group B (all p > 0.017).

CONCLUSION

Low-dose CT technology can be effectively applied to 3D printing of kidney and perinephric fat and reduce the patient's radiation dose without compromising 3D printing quality. 3D printing of kidney and perinephric fat can significantly increase the success rate of LPN and decrease OT, WIT, and EBL.

Metastatic renal Ewing's sarcoma in adult woman: Case report and review of the literature

Primary renal extra-skeletal Ewing sarcoma is a rare neoplasm, often metastatic at diagnosis, and with a poor outcome. A multimodal approach is often the treatment of choice in this aggressive neoplasm. We present a case of primary renal extra-skeletal sarcoma in a 45-year-old woman who underwent tumor resection without clear margins. After no response to the first cycle of chemotherapy, we documented an early onset of local recurrence. The patient refused any other treatment and died four months after surgery.

Clinical and Molecular Characteristics and Outcome of Cystic Partially Differentiated Nephroblastoma and Cystic Nephroma: A Narrative Review of the Literature

Simple Summary

Although renal tumors in children are mostly solid masses, cystic renal tumors also occur. The most likely diagnoses for cystic renal tumors include cystic partially differentiated nephroblastoma and cystic nephroma. Since these tumors are rare, limited information on the treatment, clinical and molecular characteristics, and outcome is available. In this review, we aim to summarize all reported patients with cystic partially differentiated nephroblastoma and cystic nephroma. We identified 113 cystic partially differentiated nephroblastoma and 167 cystic nephroma patients. Surgery was the cornerstone of treatment for both tumor types and chemotherapy was generally not recommended. Cystic nephroma was often related to DICER1-mutations and second tumors, whereas cystic partially differentiated nephroblastoma was related to somatic hyperdiploidy, although testing was rare. The outcome for both tumors is favorable. This study provides information for treatment decisions and stresses the importance of a central review of radiology and pathology, as well as referral to a clinical geneticist.

Abstract

In children presenting with a predominantly cystic renal tumor, the most likely diagnoses include cystic partially differentiated nephroblastoma (CPDN) and cystic nephroma (CN). Both entities are rare and limited information on the clinical and molecular characteristics, treatment, and outcome is available since large cohort studies are lacking. We performed an extensive literature review, in which we identified 113 CPDN and 167 CN. The median age at presentation for CPDN and CN was 12 months (range: 3 weeks–4 years) and 16 months (prenatal diagnosis–16 years), respectively. No patients presented with metastatic disease. Bilateral disease occurred in both entities. Surgery was the main treatment for both. Two/113 CPDN patients and 26/167 CN patients had previous, concomitant, or subsequent other tumors. Unlike CPDN, CN was strongly associated with somatic (n = 27/29) and germline (n = 12/12) DICER1-mutations. Four CPDN patients and one CN patient relapsed. Death was reported in six/103 patients with CPDN and six/118 CN patients, none directly due to disease. In conclusion, children with CPDN and CN are young, do not present with metastases, and have an excellent outcome. Awareness of concomitant or subsequent tumors and genetic testing is important. International registration of cystic renal tumor cohorts is required to enable a better understanding of clinical and genetic characteristics.

Management of Renal Cell Carcinoma With Extensive Caval Thrombosis Utilizing a Temporary Atrial Caval Filter Through a Combined Endovascular and Open Surgical Technique

The most common cause of neoplastic thrombotic infiltration of the inferior vena cava is renal cell carcinoma (RCC). In the present report we described a case of a patient with massive RCC and extensive neoplastic thrombosis reaching the retrohepatic tract of the inferior vena cava. After a discussion in a multidisciplinary team meeting we decided to perform a radical nephrectomy with vena cava thrombectomy along with the support of a novel removable vena cava filter in order to avoid thromboembolism during the surgical procedure. Furthermore, a preoperative renal artery embolization with a non-adhesive liquid embolic agent was performed ahead of the surgical procedure in order to reduce the risk of intraoperative bleeding. The surgical procedure performed the day after was based on a hybrid endovascular-surgical approach consisting in nephrectomy, liver derotation, cavotomy with the additional use of a novel temporary caval filter, thus reducing the risk of intraoperative thromboembolic dissemination.

Quantitative spectral CT evaluation of kidney tumors with the stretched-exponential nonlinear regression analysis model

Background

This study aimed to use the stretched-exponential nonlinear regression analysis model to explore the value of the energy spectral curve in the differential diagnosis of clear cell renal cell carcinoma (ccRCC), minimal fat renal angiomyolipoma (RAML), and hypovascular renal cell carcinoma.

Methods

Sixty-five cases with renal tumors were enrolled retrospectively who had undergone a preoperative multiphase spectral CT scan of the kidney in pre-enhance and double-phase enhanced scanning. The normalized iodine concentrations (NIC) of these lesions, normal renal cortex, and psoas major were measured and calculated. The spectral curves of these lesions and normal tissues were analyzed to calculate the stretched-exponential index (α) and b value with the stretched-exponential nonlinear regression analysis model (y=-b·X^α). The differences between α, b value, and NIC of these lesions and normal tissues in pre-enhance and two enhanced phases were compared using one-way ANOVA. The correlation between α, b value, and NIC was evaluated using the Pearson coefficient test, with significance assigned at the 5% level.

Results

There was no significant difference in α value between the groups in pre-enhance scanning. In the Cortical phase (CP), there were no significant differences in NIC and α value between minimal fat RAML and hypovascular renal cell carcinoma, or between ccRCC and the normal renal cortex. However, in the nephrographic phase (NP), a significant difference in α value was found between minimal fat RAML and hypovascular renal cell carcinoma, but no difference in NIC between them. In NP, there were significant differences in NIC and α values between ccRCC and the normal renal cortex. In CP and NP, there were significant differences between the psoas major and other groups in all parameters. For b value, in pre-enhance scanning, there was a significant difference between the psoas major and other groups, and between ccRCC and the normal renal cortex. There was no significant difference between other groups. After enhancement, in CP and NP, significant differences were observed between the psoas major and other groups in b value, but no significant differences were observed between all renal tumors and the normal renal cortex. A linear correlation was found between α values and NIC in CP (r=0.780, P=0.00) and NP (r=0.693, P=0.00). The b values and NIC had a low correlation in CP, with no correlation in NP.

Conclusions

Quantitative spectral CT with the stretched-exponential nonlinear regression analysis model may enhance the differential diagnosis ability for renal tumors. Its clinical value remains to be further explored in other types of soft tissue lesions.