Minimally invasive and robotic-assisted approaches applied to pediatric surgical oncology.

The management of pediatric tumors is complex, with surgery, chemotherapy, and radiotherapy being cornerstones in their treatment. Tumor removal is increasingly performed by a minimally invasive approach, which allows for quicker postoperative recovery and less postoperative pain. The goal of this report is to give an overview of minimally invasive surgical approaches for common pediatric tumors, with a focus on technical considerations and postoperative outcomes.

Characteristics of high frame frequency contrast-enhanced ultrasound in renal tumors.

OBJECTIVE: This study aims to analyze the characteristics of high frame rate contrast-enhanced ultrasound (H-CEUS) in renal lesions and to improve the ability for differential diagnosis of renal tumors. METHODS: A total of 140 patients with renal lesions underwent contrast-enhanced ultrasound (CEUS) examination in the First Affiliated Hospital of Nanchang University from July 2022 to July 2023. Based on the tumor pathology and the results of enhanced CT, tumor patients were divided into malignant and benign groups. All subjects were examined using gray-scale ultrasound, conventional contrast-enhanced ultrasound (C-CEUS), and H-CEUS, and their dynamic images were recorded. Two radiologists independently analyzed and recorded the results of ultrasound, C-CEUS, and H-CEUS images and statistically analyzed the features of C-CEUS and H-CEUS images. The independent sample t-test was used to compare the difference in age and maximum diameter of nodules between the benign and malignant groups. The χ2 test was used to compare the sex, mode of operation, gray-scale ultrasound characteristics, and enhancement characteristics of the two CEUS modes (enhancement mode, regression mode, enhancement degree, enhancement uniformity, enhancement or not, enhancement direction, post-enhancement boundary and range, and pseudocapsule) between the benign and malignant groups. The difference in vascular morphology of malignant nodules of varying sizes under two angiographic modes. RESULTS: There were significant differences in gender (χ2 = 10.408, P = 0.001), mode of operation (χ2 = 47.089, P < 0.001), nodule composition (χ2 = 7.481, P = 0.003), nodule echo (χ2 = 20.926, P < 0.001), necrosis (χ2 = 31.343, P < 0.001) and nodule blood flow (χ2 = 9.006, P = 0.029) between the benign and malignant groups. There were significant differences in the regression model (χ2 = 6.782, P = 0.034) and enhancement direction (χ2 = 13.771, P = 0.001) between the two radiographic techniques in the malignant group. There was a significant difference in the enhancement uniformity between the two CEUS techniques in the benign group (χ2 = 8.264, P = 0.004). There was a significant difference between the two CEUS techniques in displaying the vascular morphology in the malignant group with the maximum diameter of nodules ≤ 4.0 cm (χ2 = 11.421, P < 0.022). However, there was no significant difference between the two techniques in the malignant group with the maximum diameter of nodules > 4.0 cm. CONCLUSION: Increasing the frame rate of ultrasound images is helpful to accurately display the enhanced features and vascular morphology of renal tumors, especially for malignant tumors with a maximum diameter of ≤ 4.0 cm. Thus, H-CEUS can make up for the limitation of CEUS with regard to the display of vascular morphology.

Birt-Hogg-Dubé syndrome in an overall view: Focus on the clinicopathological prospects in renal tumors.

Birt-Hogg-Dubé syndrome (BHD) represents a rare autosomal dominant tumor predisposition syndrome characterized by skin lesions, lung cysts, and renal tumors. The predominant histological subtypes of BHD-related renal tumors include hybrid oncocytoma-chromophobe tumors, oncocytomas, and chromophobe renal cell carcinomas, all exhibiting eosinophilic/oncocytic features. Immunohistochemistry staining for KIT (CD117) and CK7 exhibits variability in these tumor types. Germline mutations in FLCN have been consistently identified. Generally, patients with BHD demonstrate a favorable prognosis with minimal metastatic potential. Nonetheless, the comprehensive elucidation of pathological characteristics of BHD remains incomplete, particularly in BHD-associated renal tumors that deviate from the previously identified subtypes, thereby complicating the differential diagnosis. In this review, we provide a comprehensive overview of BHD encompassing epidemiology, clinical manifestations, genetic and molecular pathogenesis, as well as clinical diagnostic modalities. Emphasis is placed on clinicopathological features, specifically focusing on BHD-associated renal tumors. Collectively, this review aims to present the latest insights into BHD which benefits in the early detection, therapeutic decision-making, and prognosis prediction in BHD cases, and deepen the understanding of sporadic renal tumors.

The influence of manual segmentation strategies and different phases selection on machine learning-based computed tomography in renal tumors: a systematic review and meta-analysis.

BACKGROUND: Delineating the region/volume of interest (ROI/VOI) and selecting the phases are of importance in developing machine learning (ML). The results will change when choosing different methods of drawing the ROI/VOI and selecting different phases. However, there is no related standard for delineating the ROI/VOI and selecting the phases in renal tumors to develop ML based on computed tomography (CT). METHODS: The PubMed and Web of Science were searched for related studies published until March 1, 2023. Inclusion criteria were studies that developed ML models in renal tumors from CT images. And the binary diagnostic accuracy data were extracted to obtain the outcomes, such as sensitivity (SE), specificity (SP), accuracy (ACC), and area under the curve (AUC). RESULTS: Twenty-three papers were included in the meta-analysis with a pooled SE of 87% (95% CI 85-88%), SP of 82% (95% CI 79-85%), and AUC of 91% (95% CI 89-93%) in phases; a pooled SE of 82% (95% CI 80-84%), SP of 85% (95% CI 83-86%), and AUC of 90% (95% CI 88-93%) in phases combined with delineating strategies, respectively. In all different combinations, the contour-focused and single phase produce the highest AUC of 93% (95% CI 90-95%). In subgroup analyses (sample size, year of publication, and geographical distribution), the performance was acceptable on phases and phases combined strategies. CONCLUSIONS: To explore the effect of manual segmentation strategies and different phases selection on ML-based CT, we find that the method of single phase (CMP or NP) combined with contour-focused was considered a better strategy compared to the other strategies.

Harmonica consensus, controversies, and future directions in radiotherapy for pediatric Wilms tumors.

Radiotherapy (RT) is essential for multimodality treatment of pediatric renal tumors, particularly in higher-risk and metastatic disease. Despite decades of use, particularly for Wilms tumor, there remain controversies regarding RT indications, timing, dose, and targets. To align global management, we address these issues in this international HARMONIsation and CollAboration (HARMONICA) project. There are multiple knowledge gaps and opportunities for future research including: (1) utilization of advanced RT technologies, including intensity-modulated RT, proton beam therapy, combined with image-guided RT to reduce target volumes; (2) impact of molecular biomarkers including loss of heterozygosity at 1p, 16q, and 1q gain on RT indications; (3) mitigation of reproductive toxicity following RT; (4) promotion of RT late effects research; and (5) support to overcome challenges in RT utilization in low- and middle-income countries where 90% of the world's children reside. Here, we outline current status and future directions for RT in pediatric renal tumors.

Tumor biology, biomarkers, and liquid biopsy in pediatric renal tumors.

The expansion of knowledge regarding driver mutations for Wilms tumor (WT) and malignant rhabdoid tumor of the kidney (MRT) and various translocations for other pediatric renal tumors opens up new possibilities for diagnosis and treatment. In addition, there are growing data surrounding prognostic factors that can be used to stratify WT treatment to improve outcomes. Here, we review the molecular landscape of WT and other pediatric renal tumors as well as WT prognostic factors. We also review incorporation of circulating tumor DNA/liquid biopsies to leverage this molecular landscape, with potential use in the future for distinguishing renal tumors at the time of diagnosis and elucidating intratumor heterogeneity, which is not well evaluated with standard biopsies. Incorporation of liquid biopsies will require longitudinal collection of multiple biospecimens. Further preclinical research, identification and validation of biomarkers, molecular studies, and data sharing among investigators are crucial to inform therapeutic strategies that improve patient outcomes.

Imaging of pediatric renal tumors: A COG Diagnostic Imaging Committee/SPR Oncology Committee White Paper focused on Wilms tumor and nephrogenic rests.

Malignant renal tumors account for approximately 6% of pediatric malignancies, with Wilms tumor (WT) representing approximately 90% of pediatric renal tumors. This paper provides consensus-based imaging guidelines for the initial evaluation of a child with suspected WT and follow-up during and after therapy co-developed by the Children's Oncology Group (COG) Diagnostic Imaging and Society for Pediatric Radiology (SPR) oncology committees. The guidelines for Wilms Tumor Imaging in the Society of International Pediatric Oncology (SIOP) are briefly discussed to highlight some of the differences in imaging approach.

Application of contrast-enhanced ultrasound in renal space-occupying lesion puncture biopsy.

OBJECTIVE: The purpose of this study was to investigate the utility of contrast-enhanced ultrasound (CEUS) in percutaneous renal space-occupying lesion puncture biopsy. METHODS: Ultrasound (US)-guided percutaneous needle biopsies were performed on 55 patients with renal space-occupying lesions, and the results were analyzed retrospectively. The US group included 36 patients receiving conventional US, and the contrast-enhanced ultrasound (CEUS) group included 22 patients, including 19 patients receiving CEUS directly and 3 patients receiving additional enhanced ultrasound due to the first conventional ultrasound puncture failure. The relevant data were subjected to statistical analysis. RESULTS: The results of this study showed that the successful rate of obtaining effective tissue (100% vs. 75%) and the puncture accuracy (100% vs. 88.89%) in CEUS group were significantly higher than those in US group (P < 0.05). CEUS-guided puncture biopsy of renal mass, especially in the case of urothelial carcinoma of the renal pelvis, outperforms conventional ultrasound, and the difference was statistically significant (P < 0.05). CONCLUSION: Percutaneous renal space-occupying lesion puncture biopsies aided by CEUS yield more effective tissue and improved puncture accuracy.

Comparison of robot-assisted partial nephrectomy with soft coagulation and double-layer technique for complex and non-complex tumors.

OBJECTIVES: To compare the postoperative outcomes of robot-assisted partial nephrectomy when only the inner layer is sutured (single-layer technique with soft coagulation) with those when sutures are placed in the inner and outer layers (double-layer technique) in patients with and without complex renal tumors. METHODS: This retrospective three-institution study included 371 patients with renal tumors who underwent robot-assisted partial nephrectomy with a double-layer technique or a single-layer technique with soft coagulation. Tumors that were cT1b, completely embedded, located in the renal portal, or had a RENAL score of ≥10 were considered complex. Relevant data were collected from hospital records. Propensity score matching was performed to minimize selection bias. RESULTS: Propensity score matching created 83 patient pairs with non-complex tumors and 32 with complex tumors. Regardless of tumor complexity, there was no significant difference in operation time, console time, warm ischemia time, positive surgical margin rate, or length of hospital stay between the double-layer and single-layer groups. Although Clavien-Dindo grade I-II urinomas not requiring intervention were significantly more common in the single-layer group regardless of tumor complexity, there was no significant between-group difference in the rate of decline in renal function or grade III-IV complications. CONCLUSION: Single-layer suturing with soft coagulation achieves renal function and perioperative outcomes comparable to those of double-layer suturing regardless of complexity.

Day-case robotic-assisted partial nephrectomy: feasibility and preliminary results of a prospective evaluation (UroCCR-25 AMBU-REIN study).

PURPOSE: Robotic partial nephrectomy (RPN) is a minimally-invasive technique used to treat renal tumors. A clinical pathway and prospective research protocol (AMBU-REIN) were specifically set up to establish and assess the routine use of day-case RPN. METHODS: The AMBU-REIN study was conducted in the framework of the French research network on kidney cancer UroCCR (NCT03293563). We present our initial experience of patients treated using day-case RPN and released from our hospital on the same day, focusing on patient selection, safety and patient satisfaction using the EVAN-G validated questionnaire. RESULTS: Between September 2016 and September 2019, 429 RPN were performed and 82 patients were consecutively selected for day-case RPN. Patients were managed using transperitoneal RPN with off-clamp tumorectomy for 66/82 cases. Mean tumor size was 2.7 ± 1.2 cm. There were no immediate severe postoperative complications; 7/82 patients were kept under observation overnight and discharged the following day. The follow-up at day 30 indicated postoperative complications, readmissions, and mortality rates of 1.2, 1.2, and 0%, respectively. Next-day patient satisfaction questionnaires indicated that patients were generally highly satisfied, with a mean ± standard deviation global score of 83.6 ± 10.3%. "Attention" was rated the highest overall (mean 94.8 ± 10.5%), while "pain management" scored the lowest (61.2 ± 20.5%). CONCLUSIONS: This prospective case series is the first to demonstrate the safety and feasibility of day-case RPN. For selected patients and through a dedicated, nurse-led clinical pathway, it provided a high level of patient satisfaction. Expected benefits on healthcare cost savings warrant further investigation.

Locoregional failure after postoperative flank irradiation for nephroblastoma: Results from the French cohort of the SIOP-2001 trial.

OBJECTIVE: To describe locoregional failure (LRF) after postoperative flank radiotherapy (RT) among French patients with nephroblastoma included in the Société Internationale d'Oncologie Pédiatrique (SIOP)-2001 protocol. PATIENTS AND METHODS: In selected SIOP-2001 patients, planning with simulation computed tomography (CT) scan and posttreatment CT scan demonstrating LRF were registered and analyzed. LRF was contoured and classified as in-field, marginal or out-of-field according to dose distribution. RESULTS: Total 316 French SIOP-2001 patients were treated with postoperative RT. Three patients with nephroblastoma developed LRF after flank RT. All failures were located within the retroperitoneum. In two patients, the relapse was within the RT field and in one it was classified as marginal. CONCLUSION: LRF after postoperative flank RT for nephroblastoma was rare and exclusively situated in the retroperitoneum. These results point out this region as the most at risk of local relapse. A prospective evaluation of a target volume restricted to the retroperitoneum allowing the use of modern and highly conformal radiation techniques in order to decrease dose to normal tissues shall be encouraged.

Non-Wilms' renal tumors in children: experience with 139 cases treated at a single center.

BACKGROUND: Pediatric non-Wilms renal tumors (NWRTs), which comprise a small proportion of renal tumors, are a heterogeneous group of neoplasms with variable malignant potential, mortality, and response to treatment. We performed this study to determine the clinical characteristics, management and prognosis of children with Pediatric NWRTs. METHODS: Medical records of all patients (n = 139) treated for NWRTs over a 12-year period (2008.01-2019.10) at a single center were reviewed retrospectively. RESULTS: The histopathological groups of NWRTs included malignant rhabdoid tumor of the kidney (MRTK) (n: 30, 21.6%), renal cell cancer (RCC) (n: 26,18.7%), clear cell sarcoma of the kidney (CCSK) (n: 24,17.3%), congenital mesoblastic nephroma (CMN) (n: 21,15.1%), cystic nephroma (CN) (n: 16,11.5%), metanephric tumors (n: 12, 8.6%), renal angiomyoliporma (RAML) (n: 3, 2.2%), renal primitive neuroectodermal tumor (n: 2, 1.4%), renal hemangioma (n: 2, 1.4%), inflammatory myofibroblastic tumor (n: 2, 1.4%), ossifying renal tumor of infancy (ORTI) (n: 1, 0.7%). The distribution of all malignant NWRTs, including MRTK, CCSK, RCC and PNET, according to stage was as follows: stages I (n = 26), II (n = 16), III (n = 29), and IV (n = 11). The summary table shows the treatment offered to children with NWRTs. A total of 123 children were followed up for an average of 42 months. Sixteen children were lost to follow-up. Tumor-free survival was observed in 94 children. One patient who suffered from RCC is currently receiving targeted therapy and survives with the tumor. Twenty-eight children (22.8%) died. CONCLUSIONS: Pediatric NWRTs comprise 19.1% of all renal tumors in our single center. Most NWRTs can readily be distinguished using a range of immunohistochemical markers. Molecular genetic profiling has allowed much progress in the understanding of this group of tumors, making diagnosis and classification less difficult. The mainstay treatment of malignant NWRTs, including MRTK, CCSK, RCC and PNET, is comprehensive treatment. The mainstay treatment of benign NWRTs, including RAML, CN, ORTI, CMN, metanephric tumors, and renal hemangioma, is surgical resection alone and when the tumor diameter is smaller than 7 cm and the tumor locates in one pole, NSS can be performed.

Primary Renal Synovial Sarcoma Case Series: Clinical Profile and Management of a Rare Entity.

Synovial sarcomas occur predominantly in the extremities. Primary renal synovial sarcoma is a rare entity. Very few cases have been reported in the literature. Clinical and radiological features are similar to renal cell carcinoma with the diagnosis being established after surgery based on histopathology, immunohistochemistry, and chromosome studies. There are no established guidelines on the role of adjuvant treatment in the management of this disease. We herein present a series of 3 cases managed at 2 institutions. In the current series, all patients had venous thrombus, and surgery was the mainstay of treatment. One patient received neoadjuvant chemotherapy after a preoperative biopsy which was done as she did not respond to chemotherapy for a presumptive diagnosis of Wilm's tumor.

Expanding the limits of nephron-sparing surgery: Surgical technique and mid-term outcomes of purely off-clamp robotic partial nephrectomy for totally endophytic renal tumors.

OBJECTIVES: To report surgical technique, perioperative, oncological, and mid-term functional outcomes in a single-center purely off-clamp robotic partial nephrectomy series for totally endophytic masses. METHODS: A retrospective analysis of a prospectively collected, institutional review board-approved renal cancer database was carried out to include patients with a totally endophytic renal tumor treated with off-clamp robotic partial nephrectomy between January 2013 and December 2020 at our center. Our database was queried to identify cases that had been assigned 3 points for the "E" domain of the R.E.N.A.L. nephrometry score and 3 points for the "exophytic rate" domain of the PADUA (Preoperative Aspects and Dimensions Used for an Anatomical) nephrometry score. Preoperative indocyanine green renal mass marking was performed in 33 patients, in whom the tumor was vascularized by a specific feeding artery. Surgical steps, perioperative, oncological and functional data were reported. RESULTS: Fifty-six consecutive patients with totally endophytic renal masses were treated. The median tumor diameter was 3 cm, and median PADUA and R.E.N.A.L. scores were both 10. The median operative time was 82 min. Low-grade Clavien complications occurred in two patients (3.6%) and high-grade Clavien complications were observed in four patients (7.1%). Positive surgical margins were detected in one patient; 2-year recurrence-free, cancer-specific, and overall survival rates were 100%, 100%, and 98.2%, respectively. At a median follow-up of 24 months, new onset of chronic kidney disease stage 3b occurred in one patient. At last follow-up, the median estimated glomerular filtration rate was 77 mL/min, with a median estimated glomerular filtration rate percent decrease of 5.5%. Trifecta was achieved in 91% of patients. CONCLUSIONS: Purely off-clamp robotic partial nephrectomy is a feasible and safe surgical approach, even in totally endophytic renal tumors, providing a favorable perioperative complications rate, excellent oncological outcomes, and negligible impact on renal function at mid-term follow-up. Indocyanine green preoperative marking of endophytic renal tumors represents a useful tool for rapid intraoperative identification of the mass, real-time control of resection margins, and a more precise dissection.

Recent Advances in Renal Medullary Carcinoma.

Renal medullary carcinoma (RMC) is a rare renal malignancy that has been associated with sickle hemoglobinopathies. RMC is aggressive, difficult to treat, and occurs primarily in adolescents and young adults of African ancestry. This cancer is driven by the loss of SMARCB1, a tumor suppressor seen in a number of primarily rare childhood cancers (e.g., rhabdoid tumor of the kidney and atypical teratoid rhabdoid tumor). Treatment options remain limited due in part to the limited knowledge of RMC biology. However, significant advances have been made in unraveling the biology of RMC, from genomics to therapeutic targets, over the past 5 years. In this review, we will present these advances and discuss what new questions exist in the field.

New insights in the new WHO classification of adult renal tumors.

The 5th edition of WHO classification of adult renal tumors introduced a couple of changes in existing, well established entities, as well as some new distinct renal tumors. Papillary renal cell carcinoma (RCC) is no longer divided into type 1 and type 2. Type 1 is now called “classic” variant and type 2 doesn´t exist anymore. There were long discussion about problematic type 2. According to WHO 2022 the correct name is papillary RCC (and subtype/variant should be mentioned in the description). Another important change came for clear cell papillary RCC. Because there is no convincing evidence that genuine clear cell papillary RCC can produce recurrences or metastases, it is now termed as clear cell papillary tumor. All previously reported aggressive cases are now considered misclassified clear cell RCC (mostly) or other entities. In less typical cases, genetic support of diagnosis with complex analysis of VHL gene should be added. New category “other oncocytic tumors” emerged for tumors from gray zone between renal oncocytoma and chromophobe RCC. Term hybrid oncocytic tumor should be reserved for those with hereditary Birth-Hogg-Dubé syndrome. Emerging entities, like eosinophilic vacuolated tumor (EVT) and oncocytic low-grade tumor (LOT) are mentioned, however, more work is needed for better establishment of the criteria. There is a new category of “molecularly defined renal carcinomas”, where MITf translocation RCCs are divided into TFE3 rearranged RCC with fusion partner dependent morphologic variability, and to TFEB rearranged RCC. In this group, indolent TFEB translocated RCCs are recognized, as well as potentionally aggressive RCC with TFEB gene amplification. In WHO 2016, ALK rearranged RCC was considered as emerging entity. In WHO 2022 it is listed among “molecularly defined RCC” as a distinct renal tumor with broad morphologic spectrum dependent partly on fusion partners. ELOC (TCEB1) mutated RCC is renal tumor composed of clear cell elements and huge fibromyomatous stroma. Diagnostic approach should be complex with support of immunohistochemistry (including CK7) and molecular genetic approach. However, there is overlap with MTOR pathway genes mutated RCC with fibromyomatous stroma. SMARCB1 deficient renal medullary carcinoma is high-grade invasive adenocarcinoma in patients with clinically proved sickle-cell trait and SMARCB1 deficiency.

Progress Update in Pediatric Renal Tumors.

PURPOSE OF REVIEW: Pediatric renal tumors account for 7% of new cancer diagnoses in children. Here, we will review results from recently completed clinical trials informing the current standard of care and discuss targeted and immune therapies being explored for the treatment of high risk or relapsed/refractory pediatric renal malignancies. RECENT FINDINGS: Cooperative group trials have continued to make improvements in the care of children with pediatric tumors. In particular, trials that standardize treatment of rare cancers (e.g., bilateral Wilms tumor) have improved outcomes significantly. We have seen improvements in event free and overall survival in recently completed clinical trials for many pediatric renal tumors. Still, there are subsets of rarer cancers where outcomes remain poor and new therapeutic strategies are needed. Future trials aim to balance treatment toxicity with treatment efficacy for those with excellent outcomes while identifying novel therapeutics for those with poor outcomes.

Management of renal tumors during pregnancy: case reports.

BACKGROUND: Renal tumors during pregnancy are rare and the treatment requires evaluation of both the patient and the fetus. No consensus or guidelines has been proposed or verified in this field. We successfully managed three renal tumor cases during pregnancy and reviewed the relative literature. CASE PRESENTATION: In the first renal cell carcinoma case diagnosed in the 21st week of pregnancy, laparoscopic retroperitoneoscopic partial nephrectomy was performed in the 26th week of pregnancy. In the second renal cell carcinoma case diagnosed in the 3rd week of pregnancy, laparoscopic retroperitoneoscopic radical nephrectomy was carried out after the abortion. In the third angiomyolipoma case who was diagnosed before pregnancy but received no treatment, we performed laparoscopic retroperitoneoscopic partial nephrectomy during the 17th week of pregnancy due to the rapid enlargement of the tumor. CONCLUSION: Although no consensus or guidelines for the management of renal tumors in pregnant patients has been proposed or verified, the general rules of kidney tumor management in non-pregnant patients and the guidelines for surgery in pregnancy could be referred to. Renal tumors found in pregnant patients require an individualized treatment regimen involving surgical timing, routes, techniques, and excision ranges, which should be decided by both the patients and the surgical teams.

Comparison of postoperative recovery after robot-assisted partial nephrectomy of T1 renal tumors through retroperitoneal or transperitoneal approach: A Japanese single institutional analysis.

OBJECTIVE: To evaluate the quality of recovery in patients who underwent robot-assisted partial nephrectomy and to compare the outcomes of the transperitoneal or retroperitoneal approach. METHODS: This study included 121 patients who underwent robot-assisted partial nephrectomy under general anesthesia from April 2019 to September 2019 at Tokyo Women's Medical University, Tokyo, Japan. Quality of recovery was defined according to the QoR-40 Japanese version. The participants responded to the QoR-40 Japanese version on three designated days. The patients were assigned to two groups according to the surgical approach: transperitoneal or retroperitoneal. A multivariate logistic regression analysis was carried out to identify independent factors associated with better quality of recovery. RESULTS: Out of the 121 patients, 56 (46%) and 65 (54%) patients were included in the transperitoneal and retroperitoneal group, respectively. Although the QoR-40 Japanese version scores were not different between the two groups at admission, a better quality of recovery was observed in the retroperitoneal group than in the transperitoneal group at discharge based on the total score: physical comfort, emotional state, physical independence and pain. A multivariate analysis showed that the retroperitoneal approach and male sex were associated with a better QoR-40 Japanese version score at discharge. CONCLUSIONS: A retroperitoneal approach offers better quality of recovery than a transperitoneal approach, and therefore it might represent the optimal approach in selected patients undergoing robot-assisted partial nephrectomy.

Immunoexpression of SDHB, FH, and CK20 among eosinophilic renal tumors: A tissue microarray study.

BACKGROUND: Differential diagnosis can be a challenge for eosinophilic subtypes of renal cell tumors due to their overlapping histomorphological and immunohistochemical features. We aimed to investigate the frequency of rare variants of renal cell carcinomas (RCCs) such as succinate dehydrogenase-deficient RCC (SDDRCC), hereditary leiomyomatosis and RCC (HLRCC)-associated RCC, and eosinophilic, solid, and cystic RCC (ESCRCC) in our population. MATERIALS AND METHODS: Renal tumors which could be considered in the eosinophilic tumor category were included: 91 conventional clear cell RCCs with eosinophilic cytoplasm, 72 papillary RCCs, 74 chromophobe RCCs, 88 oncocytomas, and 37 other rare subtypes. Using the tissue microarray method, succinate dehydrogenase B (SDHB), fumarate hydratase (FH), and cytokeratin 20 (CK20) antibodies were performed by immunohistochemistry. Immunohistochemistry was repeated on whole block sections for selected cases. The utility of these antibodies in the differential diagnosis was also investigated. RESULTS: Loss of SDHB expression was detected in three tumors, two of which showed typical morphology for SDDRCC. In additional two tumors, SDHB showed weak cytoplasmic expression without a mitochondrial pattern (possible-SDHB deficient). None of the tumors showed loss of FH expression. Heterogeneous reactions were observed with SDHB and FH antibodies. Only one ESCRCC was detected with diffuse CK20 positivity. CONCLUSION: SDDRCCs, HLRCC-associated RCCs, and ESCRCCs are very rare tumors depending on the population. Possible weak staining and focal loss of SDHB and FH expression should be kept in mind and genetic testing must be included for equivocal results.