Minimally invasive surgery in management of renal tumours in children

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.

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.

Minimally Invasive Techniques in Pediatric Surgical Oncology

Minimally invasive approaches to pediatric cancer surgery are increasingly used, not only for the benefits of smaller incisions, but also for better field visualization and precise dissection. Advances in technology and surgeon experience have facilitated this trend. However, the appropriate indications for its use remain to be determined, and oncologic principles should not be compromised. We discuss the current and potential future uses, and new technologies that are being developed and introduced to assist with and enhance the role of minimally invasive surgery in the management of children with cancer.

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.

Individualized robotic organ-sparing surgery in a paediatric case of renal perivascular epithelioid cell tumour

BACKGROUND

Perivascular epithelioid cell tumours (PEComas) represent a rare group of mesenchymal tumours with an unpredictable outcome. They are usually observed in middle-aged women whilst they are very rare in children, with limited cases described. Due to the rare anatomical location in kidneys, a correct diagnosis and treatment is really challenging.

METHODS

We observed and treated a case of kidney's PEComa in a 14-year-old boy.

RESULTS

An individualized approach based on anatomical (3D CT-reconstructions) and histopathological (US-guided preliminary biopsy) features lead us to perform a successful robotic-sparing surgery enabling the preservation of two-thirds of the kidney involved.

CONCLUSIONS

A meticulous preoperative planning in selected patients can lead to a minimally invasive approach even in some paediatric kidney's neoplasms.

Pediatric minimally invasive surgery for malignant abdominal tumor: Single center experience

This study examined the safety and usefulness of minimally invasive surgery (MIS) for malignant abdominal tumors in pediatric patients and analyzed the factors affecting the resection margin, operative time, and hospital stay of neuroblastoma (NBL) patients.We retrospectively reviewed data of pediatric patients who underwent MIS for malignant abdominal tumors from January 2011 to June 2017 at the Seoul National University Children's Hospital. Sex; age at operation; diagnosis; tumor location; operation-related data, such as operation time and transfusion; and follow-up data were reviewed. We divided patients into an excision group and a biopsy group. Detailed pathologic data were reviewed to analyze factors affecting the resection margin of NBL. Median value and range were calculated for all continuous variables. Mann-Whitney test and χ test were used as appropriate. P values of <.05 were considered significant.Thirty-four pediatric patients were included; 21 were boys. The median age was 4 (0.2-18) years. The most common diagnosis was NBL (17 patients; 50.0%). Three patients each were diagnosed with lymphoma, solid pseudopapillary tumor of the pancreas, and teratoma. The median tumor size was 3.4 (0.5-10.2) cm. The median operation time was 108 (55-290) minutes, and the median hospital stay was 5 (2-11) days. The number of conversions to open surgery was 4. There were no postoperative complications or mortality. There were 18 patients in the excision group and 16 in the biopsy group. Diagnosis and the number of patients receiving preoperative chemotherapy differed between the 2 groups. R0 resection of NBL was significantly higher in patients with stage 1 disease and those aged >2 years. There were no clinical factors influencing operative time or hospital stay.MIS was feasible and safe in pediatric patients with malignant abdominal tumors. R0 resection of NBL was related to age and stage.

What is the risk of local recurrence after laparoscopic transperitoneal radical nephrectomy in children with Wilms tumours? Analysis of a local series and review of the literature

BACKGROUND

To reduce long-term morbidity (adhesions-related complications and impaired quality of life due to scars), laparoscopy has been used as an alternative to open surgery in Wilms tumours (WTs). However, concerns have been raised on the risk of local recurrence after this type of resection.

OBJECTIVE

The aim was to determine the incidence of local recurrence after laparoscopic transperitoneal radical nephrectomy (LTRN).

STUDY DESIGN

We analysed 18 local cases and conducted a review of the English literature in Pubmed from 2004 to 2017 with the following keywords: (Wilms OR nephroblastoma) AND (laparoscopy OR minimally invasive surgery) AND 2004:3000. The review was conducted according to PRISMA guidelines. Data were collected independently in duplicate in a preformed Excel database. Review articles and duplicated case reports were excluded. Patients with retroperitoneoscopic or nephron-sparing surgery were also excluded.

RESULTS

One hundred and four LTRNs have been performed for WT with neoadjuvant chemotherapy in 93 cases. Tumour was ruptured preoperatively in three cases but never intraoperatively. The median volume of the tumour was 229.4 mL (3.8-776 mL). Local stage was specified in 86 cases: 49 stage I, 28 stage II, and nine stage III. Lymph nodes were sampled in 48 patients (median 2.3 [0-14] nodes). Histology was reported in 90 cases: 27 favourable and two unfavourable histology (COG); and six low, 50 intermediate, and five high-risk tumours (International Society of Paediatric Oncology). With a median follow-up of 20.5 months (1-114 months), there were four local recurrences (3.8%) at a median of 8.5 (7-9) months after surgery. Three tumours were initial local stage I (2 intermediate and 1 high risk) and one stage III. The results are presented in the Figure.

DISCUSSION

The incidence of local recurrence after LTRN is 3.8%. This is lower than previously reported after open resection. However, tumours amenable to minimally invasive surgery are smaller, with higher numbers of low stage and standard histology. Additionally, the quality of the reports is suboptimal and follow-up is relatively short.

CONCLUSION

LTRN does not seem to increase the incidence of local recurrence in WT but inclusion of patients in international protocols with prolonged and systematic follow-up is of utmost importance to carefully evaluate this risk.