Comparison between laparoscopic and open radical nephrectomy for the treatment of primary renal tumors in children: single-center experience over a 5-year period

Laparoscopic Treatment of Wilms' Tumor: Criteria of SIOP-UMBRELLA Protocol may be Updated

INTRODUCTION

Total nephrectomies for the treatment of Wilms' tumor (WT) are more and more performed by laparoscopy, although indications for this approach following the UMBRELLA guidelines are currently very restrictive. The purpose of this study was to assess the compliance to the criteria of the UMBRELLA protocol for minimally invasive approach of WT.

METHODS

This retrospective multicenter study included children operated on by laparoscopic total nephrectomy for suspected WT before 2020. Imaging was reviewed centrally.

RESULTS

Fifty-six patients (50 WT and 6 nephrogenic rests) were operated on at a median age of 3.3 ± 2.6 years. Thirteen (23%) patients had metastasis at diagnosis. The mean operative time was 213 ± 84 min. There were eight (14.3%) conversions and five peroperative complications. A local stage III was confirmed in seven (12.5%) cases, including two for tumor rupture. Only one (1.8%) of the procedures followed the SIOP-UMBRELLA indications for laparoscopy. The criterion "ring of normal parenchyma" was met only once. Conservative surgery seemed possible in ten (17.9%) cases. The extension of the tumor beyond the ipsilateral edge of the vertebra after chemotherapy and a volume over 200 mL were associated with an increased risk of conversion (p = 0.0004 and p = 0.001 respectively). After a mean follow-up of 5.2 ± 4.0 years, although there was no local recurrence, one death occurred due to metastatic progression at 15 months postoperatively.

CONCLUSIONS

The laparoscopic approach of WT beyond the UMBRELLA recommendations was feasible with low risk of local recurrence. Its indications may be updated and validated.

Robotic-assisted Pediatric Thoracic and Abdominal Tumor Resection: An Initial Multi-center Review

INTRODUCTION

Robotic-assisted minimally invasive surgery (RA-MIS) for tumor resection is an emerging technology in the pediatric population with significant promise but unproven safety and feasibility.

METHODS

A multi-center retrospective review of patients ≤18 years undergoing RA-MIS tumor resection from December 2015-March 2023 was performed. Patient demographics, perioperative variables, and complication rates were analyzed.

RESULTS

Thirty-nine procedures were performed on 38 patients (17 thoracic, 22 abdominal); 37% female and 68% non-Hispanic White. Median age at surgery was 8.3 years (IQR 5.7, 15.7); the youngest was 1.7 years-old. Thoracic operations included resections of neuroblastic tumors (n = 16) and a single paraganglioma. The most common abdominal operations included resections of neuroblastic tumors (n = 5), pheochromocytomas (n = 3), and angiomyolipomas (n = 3). Six patients underwent retroperitoneal lymph node dissection (RPLND) for paratesticular tumors. Median operating time for the cohort was 2:52 h (IQR 2:04, 4:31). Two thoracic cases required open conversion due to poor visualization and lack of working domain. All patients underwent complete tumor resection; one had tumor spillage from a positive margin (Wilms tumor). Median LOS was 1.5 days (IQR 1.1, 3.0). Postoperatively, one patient developed a chyle leak requiring interventional radiology drainage, but none required a return to the operating room.

CONCLUSIONS

Robotic-assisted surgery is safe and feasible for tumor resection in carefully selected pediatric patients, achieving complete resection with minimal morbidity and short LOS. Resection should be performed by those with robotic expertise for optimal outcomes.

LEVEL OF EVIDENCE

IV.

TYPE OF STUDY

Original Clinical Research.

Systematic Review and Meta-analysis of Laparoscopic Versus Open Radical Nephrectomy for Paediatric Renal Tumors With Focus on Wilms' Tumor

OBJECTIVE

To summarize and evaluate the outcomes of laparoscopic radical nephrectomy (LRN) and compare its safety and efficacy with open radical nephrectomy (ORN) in pediatric renal tumors (RT) and Wilms' tumors (WT).

BACKGROUND

ORN is the gold standard treatment for pediatric RT, consisting predominantly of WT. LRN is gaining popularity but remains controversial in pediatric surgical oncology.

METHODS

A systematic search was performed for all eligible studies on LRN and comparative studies between LRN and ORN in pediatric RT and WT. Meta-analysis, subgroup analysis, and sensitivity analysis were conducted. The main endpoints were cancer-related outcomes and surgical morbidity. Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines were followed.

RESULTS

No levels I to II studies were identified. LRN was feasible in nearly 1 in 5 pediatric RT and WT after neoadjuvant chemotherapy, with pooled mid-term oncological outcomes (<7% local recurrence, >90% event-free survival) comparable with those of ORN. There was no strong evidence of an increased risk of intraoperative tumor spillage, but lymph node harvest was inadequate in LRN. Large tumors crossing the ipsilateral spinal border were associated with a trend for intraoperative complications and positive margins. Pooled complications rate and hospital stay duration were similar between LRN and ORN. Long-term (>3 years) outcomes are unknown.

CONCLUSIONS

Available level III evidence indicates that LRN is a safe alternative to ORN for carefully selected cases, with similar spillage rates and mid-term oncological outcomes. However, there was no advantage in surgical morbidity and lymph node harvest was inadequate with LRN. Tumor-matched-group studies with long-term follow-up are required.

LEVEL OF EVIDENCE

Level III.

[Laparoscopic nephrectomies and kidney resections in children]

OBJECTIVE

To present the experience of laparoscopic nephrectomies and kidney resections in children.

MATERIAL AND METHODS

There were 28 minimally invasive surgeries for renal tumors between July 2015 and March 2023 (92 months). There were 16 (57%) boys and 12 (43%) girls who underwent 22 nephrectomies and 6 kidney resections. The median age of patients was 54 (38; 76.5) months.

RESULTS

In the laparoscopic nephrectomy group, the median surgery time was 135 (108-188) min, blood loss - 10 (3.75-15) ml. Total resection was confirmed in all patients. In the group of minimally invasive kidney resections, these values were 182.5 (157.5; 265) min and 50 (42.5; 117.5) ml, respectively. Histological examination confirmed total resection in all patients. In both groups, none patient developed postoperative complications. Event-free survival was 86.72% with a median follow-up of 82 months, and local recurrence-free survival was 95.8% with a median follow-up of 89.8 months.

CONCLUSION

Minimally invasive nephrectomies and resections are safe in children in case of careful patient selection.

Technical advances in the surgical management of Wilms tumors in children

Surgery is one of the cornerstones of Wilms tumor treatment. In this article, we present technical advancements that are finding their way into the armamentarium of pediatric cancer surgeons. We discuss the current approaches, challenges, opportunities, and future directions of minimally invasive surgery (laparoscopic and robotics), image-guided surgery, and fluorescence-guided surgery. Furthermore, we discuss the use of intraoperative ultrasonography, as well as the use of new techniques to improve the quality of lymph node sampling.

Evidence-based surgical guidelines for treating children with Wilms tumor in low-resource settings

BACKGROUND

Survival of Wilms tumor (WT) is > 90% in high-resource settings but < 30% in low-resource settings. Adapting a standardized surgical approach to WT is challenging in low-resource settings, but a local control strategy is crucial to improving outcomes.

OBJECTIVE

Provide resource-sensitive recommendations for the surgical management of WT.

METHODS

We performed a systematic review of PubMed and EMBASE through July 7, 2020, and used the GRADE approach to assess evidence and recommendations.

RECOMMENDATIONS

Initiation of treatment should be expedited, and surgery should be done in a high-volume setting. Cross-sectional imaging should be done to optimize preoperative planning. For patients with typical clinical features of WT, biopsy should not be done before chemotherapy, and neoadjuvant chemotherapy should precede surgical resection. Also, resection should include a large transperitoneal laparotomy, adequate lymph node sampling, and documentation of staging findings. For WT with tumor thrombus in the inferior vena cava, neoadjuvant chemotherapy should be given before en bloc resection of the tumor and thrombus and evaluation for viable tumor thrombus. For those with bilateral WT, neoadjuvant chemotherapy should be given for 6-12 weeks. Neither routine use of complex hilar control techniques during nephron-sparing surgery nor nephron-sparing resection for unilateral WT with a normal contralateral kidney is recommended. When indicated, postoperative radiotherapy should be administered within 14 days of surgery. Post-chemotherapy pulmonary oligometastasis should be resected when feasible, if local protocols allow omission of whole-lung irradiation in patients with nonanaplastic histology stage IV WT with pulmonary metastasis without evidence of extrapulmonary metastasis.

CONCLUSION

We provide evidence-based recommendations for the surgical management of WT, considering the benefits/risks associated with limited-resource settings.

Oncologic Fidelity of Minimally Invasive Surgery to Resect Neoadjuvant-Treated Wilms Tumors

Background

The Children's Oncology Group recommends upfront resection of Wilms tumor (WT), however, unique scenarios warrant neoadjuvant chemotherapy and delayed resection. We hypothesized that in the context of neoadjuvant chemotherapy, minimally invasive surgery (MIS) to resect WT achieves equivalent oncologic fidelity and better maintains therapy schedules.

Methods

A retrospective analysis of WT treated between 2010-2021 at a free-standing children's hospital was performed. Patient and disease specific characteristics were collected, and pre-resection tumor volumes (TV) were calculated. Impact of MIS or open resection on oncologic fidelity and time to resume chemotherapy was analyzed.

Results

For the study period, 62 patients were treated for 65 WT, and 14 patients (22.6%) received neoadjuvant chemotherapy to treat 17 WT (26.2%): 7 Stage I (all predisposition syndromes), 2 stage III, 7 stage IV, and 1 stage V (bilateral). MIS was utilized to resect 6 WT from 5 patients. For partial nephrectomy, pre-resection TV was 0.38 ml if MIS and 10.38 ml if open ( P = .025). For radical nephrectomy, pre-resection TV was 31.58 ml if MIS and 175.00 ml if open ( P = .101). No significant differences between surgical approach were detected regarding pathologic variables or survival. Epidural use was significantly greater with open procedures ( P = .001). Length of stay was 2.00 days after MIS compared to 6.00 for open resection ( P = .004). Time to resume chemotherapy was 7.00 days after MIS versus 27.00 for open ( P = .004).

Conclusion

After neoadjuvant chemotherapy for WT, MIS partial and radical nephrectomies achieved equivalent oncologic fidelity, reduced epidural use and post-operative stays, and better maintained adjuvant therapy timelines when compared to open resections.

Open versus minimally-invasive surgical techniques in pediatric renal tumors: A population-level analysis of in-hospital outcomes

INTRODUCTION

Minimally-invasive surgery (MIS) has been adopted slowly in pediatric oncology. We attempted to describe contemporary national trends in MIS use; we hypothesized that adolescents (who are more likely to have relatively small renal cell carcinomas) would have a higher proportion of MIS than younger children (who are more likely to have relatively large Wilms tumors) and that this relationship would vary by region.

OBJECTIVE

To explore whether pediatric urologic oncology outcomes vary by patient age or by surgical technique.

METHODS

We queried the 1998-2014 National Inpatient Sample (NIS) and included encounters in children aged ≤ 18 y, ICD-9 diagnostic code for renal tumor, and procedure code for open or MIS partial or radical nephrectomy. All analyses used weighted descriptive statistics and outcomes are compared based on age group (</>10 y) or surgery type; Wald-Chi square test was used for differences in proportions and unadjusted weighted ANOVA was used to test for differences in means.

RESULTS

9259 weighted encounters were included; 91% were <10 years old and 50.7% were female. MIS surgery accounted for 1.8% of encounters; there was a difference in proportions by age group (1% <9 y vs. 9.9% >9 y, p < 0.01). The proportion of surgery type was similar across regions within age groups, however. Complications occurred in 13.3% of encounters; mean inpatient length of stay was 8.9 days (SD: 0.3); mean cost was $ 34,457.68 (SD: $1197.00). There was no evidence of a difference between surgery type and proportion of post-operative complications, mean inpatient length of stay or mean inpatient cost.

DISCUSSION

The admission-based, retrospective design of NIS left us unable to assess long-term outcomes, repeated admissions, or to track a particular patient across time; this is particularly relevant for oncologic variables on interest such as tumor stage or event-free survival. We were similarly limited in evaluating the effect of pre-surgical referral patterns on patient distributions.

CONCLUSION

In this preliminary descriptive analysis, MIS techniques were infrequently used in children, but there was a higher proportion of MIS use among adolescents. There were similar proportions of surgery type across geographic regions within the United States. Whether this infrequent usage is appropriate is as yet unclear given the lack of Level I evidence regarding the relative merits of MIS and open surgery for pediatric and adolescent renal tumors.

Renal cell carcinoma in children and adolescents: Single-center experience and literature review

Renal cell carcinoma (RCC) is infrequent in the pediatric population. In addition, till date, only a few reports have summarized the characteristics of pediatric RCC and differences between pediatric and adult RCC. Therefore, the current study aimed to investigate the clinical characteristics of RCC in children and adolescents, and identify the differences between children and adolescent patients and adult patients through literature retrieval.The data of 13 pediatric patients diagnosed with RCC at the Children's Hospital of Zhejiang University School of Medicine between 2005 and 2019 were retrospectively analyzed.Three patients were aged <5 years, 2 were aged 6 to 10 years, and 8 were aged 11 to 18 years. Among the 13 patients, common clinical manifestations included abdominal pain in 5 patients, gross hematuria in 4, and an abdominal mass in 1, while the other 3 patients were incidentally detected after an abdominal contusion. The pathological types were microphthalmia family translocation RCC in 9 patients, clear-cell RCC in 2, papillary RCC in 1, and unclassified in 1. All the children underwent radical nephrectomy, including 2 patients with advanced disease who underwent preoperative transcatheter arterial chemoembolization. The mean follow-up time was 58.6 months. Two patients died after 4 and 17 months of follow-up, respectively.In conclusion, microphthalmia family translocation renal cell carcinoma is the predominant type of pediatric RCC associated with advanced tumor stage. The early diagnosis and treatment of pediatric patients is important for improving prognosis. Nevertheless, future studies are urgently needed to determine the treatment for pediatric advanced RCC to increase the survival rate.

A single centre matched pair series comparing minimally invasive and open surgery for the resection of pediatric renal tumours

INTRODUCTION

Minimally invasive nephrectomy (MIN)for the resection of pediatric renal tumors is controversial. We compared patients who underwent laparoscopic MIN according to our unit protocol with matched patients who underwent open surgery (ON).

METHOD

A single centre retrospective analysis of prospectively collected data for MIN. Tumor volume was calculated from pre-operative imaging and volume matched ON patients were identified from the regional tumor database. Demographics, complications, operative time, length of stay, number of nodes resected, status of margins, radiotherapy (RT)requirement, length of follow-up and outcomes were analysed.

RESULTS

Fourteen MINs performed between September 2016 and 11/2019 (M:F 5:9; median age 37 (range 2-73)months) were matched with ON controls (7:7 M:F, median age 42 (1-74)months). Diagnoses in the MIN group were Wilms Tumour (WT)in11 and one each of mesoblastic nephroma (MN), malignant rhabdoid tumour of the kidney (MRTK), nephroblastomatosis and in the ON group were 13 WT and 1 MN. Median operating time for MIN was 180 (125-300)minutes, with 4 conversions and 155 (1-3-480)minutes in ON. There were no intra-operative ruptures. Three tumors in each group had positive margins. A median of 4 (0-6) nodes were removed during MIN and 4 (2-22) during ON. Median length of stay (LoS)was 4 (2-15)days following MIN and 4 (2-9) following MIN. Six ON and 3 MIN patients required radiotherapy. Differences were not significant. Median follow up of 30 (6-44)months for MIN and 73 (34-109)months for ON patients was significantly different. There have been no local recurrences but the child with MRTK died following brain tumor recurrence.

CONCLUSION

MIN for pediatric renal tumors has similar short term outcomes to ON in carefully selected patients.

Minimally invasive surgery for pediatric renal tumors: A systematic review by the APSA Cancer Committee

Minimally invasive nephrectomy is performed routinely for adult renal tumors and for many benign pediatric conditions. Although open radical nephroureterectomy remains the standard of care for Wilms tumor and most pediatric renal malignancies, there are an increasing number of reports of minimally invasive surgery (MIS) for those operations as well. The APSA Cancer Committee performed a systematic review to better understand the risks and benefits of MIS in pediatric patients with renal tumors.

METHODS

The search focused on MIS for renal tumors in children and followed the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) checklist. The initial database search identified 491 published articles, and after progressive review of abstracts and full-length articles, 19 were included in this review.

RESULTS

There were two direct comparison studies where open surgery and MIS were compared. The remaining studies reported only on minimally invasive nephrectomy. Across all studies, there were a total of 151 patients, 126 of which had Wilms tumor and 10 patients had RCC. 104 patients had MIS, with 47 patients having open surgery. In the two studies in which open surgery and MIS were directly compared, more lymph nodes were harvested during open surgery (median = 2 (MIS) vs 5 (open); mean = 2.47 (MIS) vs 3.8 (open)). Many noncomparison studies reported the harvest of 2 of fewer lymph nodes for Wilms tumor. Several MIS patients were also noted to have intraoperative spill or positive margins. Survival between groups was similar.

CONCLUSIONS

There is a lack of evidence to support MIS for pediatric renal tumors. This review demonstrates that lymph node harvest has been inadequate for MIS pediatric nephrectomy and there appears to be an increased risk for intraoperative spill. Survival data are similar between groups, but follow-up times were inconsistent and patient selection was clearly biased, with only small tumors being selected for MIS.

TYPE OF STUDY

Review article.

LEVEL OF EVIDENCE

III.

Wilms tumor: a review of current surgical controversies

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

Ossifying Renal Tumor of Infancy: Laparoscopic Treatment and Literature Review

We present an unusual case of a rare ossifying renal tumor of infancy. A 6-month-old male initially presented with gross hematuria and without any palpable abdominal mass. Renal ultrasound and MRI showed a right lower pole, calcified, endophytic renal mass. Laparoscopic radical nephrectomy was performed without complications. Pathology demonstrated an ossifying renal tumor of infancy. We report this case, in addition to a review of the literature for similar cases, to highlight a rare renal tumor in infancy that can be managed laparoscopically.

Laparoscopic total nephrectomy for Wilms tumor: Towards new standards of care

INTRODUCTION

Laparoscopic total nephrectomy (LN) in malignant pediatric tumors remains controversial. For selected patients undergoing pre-operative chemotherapy in referral centers, LN has so far shown comparable results to the standard open technique.

PURPOSE

To describe the inclusion criteria and preliminary results of laparoscopic nephrectomies (LN) for the treatment of unilateral Wilms tumors (WT).

MATERIAL AND METHODS

Between November 2010 and January 2016, a retrospective study of patients with WT and undergoing pre-operative chemotherapy was performed. Inclusion criteria for candidates for LN were: unilateral tumors without venous invasion and central kidney localization. Tumor size and vascular thrombus were estimated with pre-operative computed tomography (CT) scan. Overall survival and recurrence rates were evaluated.

RESULTS

Among 105 patients with WT, 14 underwent LN. Tumor bleeding or the lack of response to chemotherapy were not exclusion criteria. Median tumor volume for the patients undergoing LN was 71.5 cc (range 7-169). Patients with small tumors localized near the renal pole and candidates for nephron sparing surgery (NSS) were excluded. Estimated 5-year overall survival for all patients with WT during this period was 88.7% (88.1-103.1). Two patients underwent conversion. No recurrence or related death was found at a mean 32- month follow-up period.

DISCUSSION

Reproducing the steps of the open nephrectomy when performing LN for malignant tumors allowed comparable oncologic results to the conventional procedure. However, upstaging of the tumor was not admissible and has become the main goal when approaching these patients laparoscopically. Preliminary results showed that the incidence of intraoperative rupture and incomplete node sampling were not an issue when comparing LN to open nephrectomy. On the other hand, LN for malignant tumors requires experience in advanced laparoscopy and oncologic surgery. Pre-operative chemotherapy changes the tumor's consistency and this is the key point as to why these patients are amenable to be approached laparoscopically. Lifting the tumor along with the fat to avoid capsule fraction, as well as changing the lens to the lateral port to achieve a correct view for lymph node sampling are some of the considerations when performing LN.

CONCLUSIONS

Preliminary data suggest that LN for WT is feasible and has promising results in terms of event-free and overall survival. In patients undergoing pre-operative chemotherapy the correct selection for LN is crucial. Following the basic oncological precepts and in experienced centers, LN represents a plausible modality in the care of these patients.

Laparoscopic nephrectomy for Wilms' tumor: Can we expand on the current SIOP criteria?

INTRODUCTION

Wilms' tumor now has a good overall prognosis with open radical nephrectomy having been the mainstay of surgical treatment. Recently laparoscopic nephrectomy (LN) has been growing in popularity. The aim of our study was to review our indications and outcomes for laparoscopic resections for Wilms' tumor and compare indications with International Society of Paediatric Oncology (SIOP) criteria for LN.

MATERIAL AND METHODS

Patient demographics, preoperative management, surgical data, respect of SIOP criteria, complications, disease outcome, and follow-up were recorded on consecutive children who underwent nephrectomy for Wilms' tumor.

RESULTS AND DISCUSSION

Fifty-four consecutive children with Wilms' tumor underwent a nephrectomy; 20 had a LN (Table). Nine of 20 (45%) patients who had LN did not meet SIOP criteria for LN. No patients had an intraoperative tumor rupture and one patient had positive margins because of preoperative rupture. There were two conversions: one caused by difficulty accessing the renal hilum and the other caused by difficulty maintaining oxygen saturations. There was one local recurrence.

CONCLUSION

SIOP criteria are conservative and safe. Indications can be extended for teams experienced in surgical oncology and laparoscopy after agreement at a multidisciplinary meeting (MDM).

Feasibility of laparoscopic tumour nephrectomy in children

AIMS

The laparoscopic approach to tumour nephrectomy in children is controversial. We therefore reviewed our institution's cases of tumour nephrectomy (laparoscopic, open, and converted) to better understand which is suitable for this approach, what factors prevent it, and whether one can excise tumours greater than the CCLG recommendation of 300 ml.

METHODS

All tumour nephrectomies performed between 2002 and 2016 were identified using our surgical database. Further data were gathered from radiology and pathology databases. Those with nonrenal tumours or having a partial nephrectomy were excluded. Tumour maximum diameters, volumes, and ratios to contralateral kidneys were calculated. A Mann-Whitney U was used to compare the groups.

RESULTS

Forty-three cases were included. Fifteen procedures were completed laparoscopically (35%), and a further 3 converted. The median age at surgery was 2.5 years (range 0-10) in the laparoscopic group and 2 years (range 0-15) in the open group. There was a significant difference (P < 0.05) between the laparoscopic and open groups for: median maximum diameter (10cm vs 12.25cm), median volume (155 ml vs 459 ml), maximum diameter ratio (1.22 vs 1.75), and volume ratio (3.8 vs 11.2).

CONCLUSION

Tumours in the laparoscopic group were significantly smaller, but it was possible to excise tumours more than 300 ml. Difficulties in excision related to tumour size relative to the abdomen. Therefore, a ratio of tumour to contralateral kidney may be a better guide to safe excision than an overall volume cutoff. From our series, the laparoscopic approach is likely to be achievable if the volume ratio is ≤ 8.1.

LEVEL OF EVIDENCE

Level 3.

Open versus minimally invasive surgical approaches in pediatric urology: Trends in utilization and complications

OBJECTIVE

Minimally invasive surgery (MIS) techniques are anecdotally reported to be increasingly used, but little objective data supports this. Our objective was to assess trends in MIS utilization across various procedures in pediatric urology and to compare postoperative complication rates between MIS and open procedures.

METHODS

We analyzed the 1998-2012 Nationwide Inpatient Sample. We identified children (<18 years old) undergoing open and MIS inpatient procedures and any in-hospital post-operative complications that occurred during that postoperative hospitalization. We utilized propensity score matching and multivariable logistic regression to adjust for confounding factors.

RESULTS

We identified 163,838 weighted encounters in the "overall cohort," 70,273 of which were at centers performing more than five MIS procedures over the years studied. Use of MIS techniques increased significantly over time for several procedures, most prominently for nephrectomy (Fig.). The overall rate of complications was lower in patients undergoing MIS compared with open surgery (6% vs. 11%, p < 0.001). Specialized centers had a significantly lower overall rate of complications than unspecialized centers (9% vs. 12%, p < 0.001). Within specialized centers, MIS had lower complication rates than open procedures (7% vs. 9%, p < 0.001); this finding was consistent even after adjusting for other factors (OR 0.71, p = 0.02).

DISCUSSION

Limitations include that these data may not be generalizable to encounters not in the sample pool. As a large, retrospective, administrative database, NIS may be affected by miscoding bias - rendering our analysis sensitive to the accuracy of procedure coding in NIS. Although the accuracy level of NIS is high for an administrative database, it is possible at least some portion of our cohort may be incorrectly coded. Further, the NSQIP complications we identified may represent associated comorbidities and not true postoperative complications, as NIS does not provide temporal relationships between different diagnosis codes. Despite these limitations, we note that the NIS database is rigorously monitored and audited for coding accuracy and, therefore, represents a reasonably reliable panorama of the characteristics of an inpatient surgical cohort. However, it is important to note that the choice of operative modality is, undoubtedly, multifactorial and patient/setting-specific.

CONCLUSIONS

There is increasing use of MIS for pediatric urology procedures, although utilization rates vary among procedures. MIS was associated with a lower postoperative complication rate than for open procedures. Higher-volume MIS centers have a lower complication rate than lower-volume centers.

Laparoscopic Versus Open Radical Nephrectomy for Renal Cell Carcinoma: a Systematic Review and Meta-Analysis

BACKGROUND

The aim of this study is to summarize and quantify the current evidence on the therapeutic efficacy of laparoscopic radical nephrectomy (LRN) compared with open radical nephrectomy (ORN) in patients with renal cell carcinoma (RCC) in a meta-analysis.

METHODS

Data were collected by searching Pubmed, Embase, Web of Science, and ScienceDirect for reports published up to September 26, 2016. Studies that reported data on comparisons of therapeutic efficacy of LRN and ORN were included. The fixed-effects model was used in this meta-analysis if there was no evidence of heterogeneity; otherwise, the random-effects model was used.

RESULTS

Thirty-seven articles were included in the meta-analysis. The meta-analysis showed that the overall mortality was significantly lower in the LRN group than that in the ORN group (odds ratio [OR] =0.77, 95% confidence interval [CI]: 0.62-0.95). However, there was no statistically significant difference in cancer-specific mortality (OR=0.77, 95% CI: 0.55-1.07), local tumor recurrence (OR=0.86, 95% CI: 0.65-1.14), and intraoperative complications (OR=1.27, 95% CI: 0.83-1.94). The risk of postoperative complications was significantly lower in the LRN group (OR=0.71, 95% CI: 0.65-0.78). In addition, LRN has been shown to offer superior perioperative results to ORN, including shorter hospital stay days, time to start oral intake, and convalescence time, and less estimated blood loss, blood transfusion rate, and anesthetic consumption.

CONCLUSION

LRN was associated with better surgical outcomes as assessed by overall mortality and postoperative complications compared with ORN. LRN has also been shown to offer superior perioperative results to ORN.

Distinguishing pediatric and adolescent renal cell carcinoma from other renal malignancies

PURPOSE

Renal cell carcinoma (RCC) represents a small proportion of renal malignancies early in life. Distinguishing RCC from other malignancies is important as treatment strategies may differ. We analyze the Surveillance Epidemiology, and End Results (SEER) database to identify predictive factors of RCC in the pediatric population with renal tumors.

METHODS

We queried SEER to identify patients from ages 0 to 19 diagnosed with a renal malignancy between 1973 and 2013. Cases were sorted using histology and site codes. Age-adjusted standardized incidence rates (SIR) were calculated. We compared differences in characteristics between cancer types. A logistic regression model and a nomogram were created to identify predictors of RCC.

RESULTS

A total of 3,670 patients were identified, of which 281 (7.7%) were diagnosed with RCC. The SIR of RCC increased with age. After age 12, RCC was found in >50% of all newly diagnosed cases. On multivariate analysis, RCC was associated with smaller tumor size (P < 0.001), increasing age (P < 0.001), black race (P < 0.001), and localized stage (P < 0.001). The nomogram predicted RCC pathology with a concordance index of 0.965.

CONCLUSIONS

RCC in childhood and adolescence is relatively uncommon; however, it accounts for >50% of renal malignancies after age 12. For every year of increasing age, the odds of having an RCC diagnosis are increased by 50%. The odds of a renal tumor being RCC are increased in black children, those with localized disease, and those with smaller tumors. In these specific populations, RCC should be favored in the differential diagnosis of the renal mass.

The Evolving Role of Minimally Invasive Surgery in Pediatric and Adolescent Urologic Oncology

OBJECTIVE

This review aims at evaluating the current status of minimally invasive surgery at the difficult crossroad between the attractiveness of innovation faced against the solid outcomes offered by the current gold standard, specifically concerning pediatric and adolescent urologic oncology conditions.

METHODS

This is a critical review of the literature and current paradigms on the use of minimally invasive surgery for pediatric and adolescent urologic oncology cancers. Focus is mainly on the use of laparoscopy for the treatment of Wilms' tumors but other neoplasms are also discussed.

RESULTS

We draw parallels with other similar pathologies, respecting critical lessons from international cooperative study groups. We discuss various aspects of the pros and cons of minimally invasive surgery in this patient population and make a case for the development of dedicated pediatric surgeons for urologic cancer.

CONCLUSION

Herein we draft a proposal suggesting a way forward with the adoption of reasonable paradigm shifts founded on carefully conducted studies for the introduction of minimally invasive surgery in the care of pediatric and adolescent urologic cancer.

Videolaparoscopic radical nephrectomy after chemotherapy in the treatment of Wilms' tumor: Long-term results of a pioneer group

INTRODUCTION

A high cure rate for Wilms' tumor has been achieved using a multidisciplinary approach. The natural step forward is to offer the benefits of a minimally invasive technique for surgery, which is an obligatory part of treatment. Nevertheless, some authors resist using videolaparoscopic radical nephrectomy (VRN) because of concerns about reducing the cure index.

METHODS

The present study included children with unilateral Wilms' tumor treated from December 2003 to December 2015 with neoadjuvant chemotherapy followed by VRN. Patients were selected based on the size of their tumors compared with the contralateral kidney, and on their stature.

RESULTS

VRN was performed in 24 patients of age range 10-93 months, with an average of 38.04 ± 23.37 months. The tumoral kidney's largest diameter after chemotherapy averaged 10% of a patient's height. There was no tumor rupture or spillage and no patient presented intra or immediate postoperative complications, except for prolonged ileum in two patients. One patient required intraoperative transfusion because of preoperative anemia. Another developed a late herniation in the umbilical port that required surgical correction. After an average of 6.65 years of follow-up, two patients presented relapse: one with a stage IV disease had relapse in the lung and another with a stage III, involving the liver, had local relapse because of an unwanted delay in the adjuvant treatment.

CONCLUSION

VRN can be considered a feasible alternative to open surgery in selected cases of children with Wilms' tumor. The present experience shows that besides the benefits of minimally invasive procedures and better cosmetic results, there is no evidence of increased tumor rupture or spillage, peritoneal or port site metastasis, and the long-term oncological results are the same as open procedures.

"Zero-Ischemia" Laparoscopic-assisted Partial Nephrectomy for the Management of Selected Children With Wilms Tumor Following Neoadjuvant Chemotherapy

OBJECTIVE

To describe the experience and technique of zero-ischemia laparoscopic-assisted partial nephrectomy at The Hospital for Sick Children, as an alternative to the traditional open approach for nephron-sparing surgery (NSS) in selected children with Wilms tumor (WT).

MATERIALS AND METHODS

Patients with diagnosis of WT treated with neoadjuvant chemotherapy and who underwent laparoscopic-assisted NSS at the Hospital for Sick Children from 2012 to 2016 were identified and their charts were reviewed retrospectively. Patients underwent laparoscopic exploration, lymph node sampling, kidney mobilization, vascular control, and adrenal sparing. This was followed by open NSS through a small flank incision; no clamping of the hilum or major renal branches was performed.

RESULTS

Six patients were identified; all patients underwent successful resection. One patient required radical nephrectomy due to inability to safely define negative margins. Tumors ranged in size from 0.9 to 5.6 cm in diameter. Mean operating time was 293 ± 50.2 minutes, with an average duration of pneumoperitoneum of 216 ± 27 minutes. Intraoperative blood loss was negligible. No tumor spillages occurred. Postoperative pathology revealed negative margins in all resected specimens. One case of urine leak occurred postoperatively, which resolved spontaneously. Renal function was preserved in all children. At a mean follow up of 11.5 months, all patients have been recurrence free.

CONCLUSION

The herein presented strategy allows for safe nephron-sparing resection of selected WT with acceptable morbidity, good short-term disease-free survival, and potentially better cosmesis and recovery than traditional open surgery. This preliminary experience suggests that minimally invasive options for NSS in children merit further evaluation.

Minimally invasive surgery in management of renal tumours in children

Minimally invasive surgery (MIS) in the management of malignant and benign renal tumours in children is gradually becoming more common. Experience is limited and restricted to case reports, retrospective chart reviews and a few cohort studies. There are currently no randomized controlled trials or controlled clinical trials comparing the laparoscopic and open surgical approach for the management of renal tumours in children. MIS may offer the same oncologic outcome in malignant renal tumours whilst providing the advantages associated with MIS in correctly selected cases. The technique for tumour resection has been shown to be feasible in regards to the recommended oncologic principles, although lymph node sampling can be inadequate in some cases. Preliminary reports do not show an increased risk of tumour rupture or inferior oncologic outcomes after MIS. However, the sample size remains small and duration of follow-up inadequate to draw any firm conclusions. Implementation of MIS is lacking in the protocols of the major study groups, and standardized recommendations for the indications and contra-indications remain undefined. The objective of this article is to present a review of the literature on the role of MIS in the management of renal tumours in children, with the main focus on Wilms' tumour (WT). Further studies on MIS in renal tumours are required to evaluate the incidence of oncological complications such as complete tumour resection and intra-operative tumour spillage. A long-term follow-up of patients managed by MIS is essential to compare recurrence rates and overall survival rates.