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.

Surgery for the complex Wilms tumour

The prognosis of children with Wilms tumour has greatly improved since the introduction of adjuvant radiotherapy and chemotherapy more than 70 years ago with a current overall long-term survival approaching 90%. Before this, surgery was the only option with around 20% survival, even in low-risk categories. The focus is now on management options for those patients in specific subgroups, who continue to have lower event-free survival and who suffer from the long-term effects of treatment. These include those with anaplastic histology, bilateral Wilms, biologically high-risk tumours and those that relapse (Aldrink et al. in J Pediatr Surg 54(3):390-397, 2019). The major advances that have already been made in risk assessment and tailoring the chemotherapy/radiotherapy to achieve maximum advantage with minimum toxicity and long-term morbidity have been predicated on safe and complete resection and staging of the tumour. There are, however, still surgical challenges faced with respect to resection of 'complex' tumours; thus, surgeons need to understand their role and advance their expertise in the overall treatment of children with Wilms tumour. These include very large tumours not responding to chemotherapy, ruptured tumours, tumours with intravascular invasion into the inferior vena cava (± 10%), heart and hepatic veins (± 4%) and Wilms tumours in horseshoe kidneys (< 1%) (Kieran and Ehrlich in Urol Oncol https://doi.org/10.1016/j.urolonc.2015.05.029, 2015). This review describes surgical strategies and techniques used in these situations, gleaned from the authors' experience in the surgical management of over 300 children with Wilms tumours in our centres over the last 30 years.

Agreement between clinicoradiological signs at diagnosis and radiohistological analysis after neoadjuvant chemotherapy of suspected Wilms tumor rupture: Consequences on therapeutic choices

INTRODUCTION

According to SIOP criteria, every patient presenting with preoperative Wilms tumor (WT) rupture must receive abdominal radiotherapy. Neoadjuvant chemotherapy reduces tumor volume and is responsible for the development of peritumoral capsule formation, which can mask tumor rupture on histological analysis, while it was clinically or radiologically obvious at diagnosis. Yet, there are no protocol recommendations for this particular presentation.

OBJECTIVES

Study the agreement between clinicoradiological signs and histological confirmation after neoadjuvant chemotherapy of suspected WT rupture and describe the therapeutic choices arising in consequence.

METHODS

Descriptive retrospective study on a monocentric series of patients with WT between June 1991 and August 2017.

RESULTS

Out of 71 patients, 28 presented with suspected tumor rupture. We observed good agreement between clinical and radiological signs of suspected rupture (κ coefficient: 0.67). However, we assessed poor agreement between these signs and histological conclusions after neoadjuvant chemotherapy (κ coefficient: 0.27). Only five patients with clinicoradiological signs were overtreated with radiotherapy while tumor rupture had been refuted after histological review. The notion of abdominal trauma and the presence of intraperitoneal effusion seemed to guide collegial decision to overtreat these patients. No statistical difference in survival between patients with and without suspicion of tumor rupture at diagnosis was observed.

CONCLUSION

This study highlights the need for recommendations in case of discrepancy between radiological and histological signs of rupture at diagnosis and after neoadjuvant chemotherapy. A study with stronger statistical power is necessary to define criteria that would lead to optimization of treatment in this context.

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.

Comparing oncologic outcomes after minimally invasive and open surgery for pediatric neuroblastoma and Wilms tumor

BACKGROUND

Minimally invasive surgery (MIS) has been widely adopted for common operations in pediatric surgery; however, its role in childhood tumors is limited by concerns about oncologic outcomes. We compared open and MIS approaches for pediatric neuroblastoma and Wilms tumor (WT) using a national database.

METHODS

The National Cancer Data Base from 2010 to 2012 was queried for cases of neuroblastoma and WT in children ≤21 years old. Children were classified as receiving open or MIS surgery for definitive resection, with clinical outcomes compared using a propensity matching methodology (two open:one MIS).

RESULTS

For children with neuroblastoma, 17% (98 of 579) underwent MIS, while only 5% of children with WT (35 of 695) had an MIS approach for tumor resection. After propensity matching, there was no difference between open and MIS surgery for either tumor for 30-day mortality, readmissions, surgical margin status, and 1- and 3-year survival. However, in both tumors, open surgery more often evaluated lymph nodes and had larger lymph node harvest.

CONCLUSION

Our retrospective review suggests that the use of MIS appears to be a safe method of oncologic resection for select children with neuroblastoma and WT. Further research should clarify which children are the optimal candidates for this approach.

Pediatric oncologic endosurgery

Despite increasing popularity of minimal-invasive techniques in the pediatric population, their use in diagnosis and management of pediatric malignancy is still debated. Moreover, there is limited evidence to clarify this controversy due to low incidence of each individual type of pediatric tumor, huge diversity of the disease entity, heterogeneity of surgical technique, and lack of well-designed studies on pediatric oncologic minimal-invasive surgery. However, a rapid development of medical instruments and technologies accelerated the current trend toward less invasive surgery, including oncologic endosurgery. The aim of this article is to review current literatures about the application of the minimal-invasive approach for pediatric tumors and to give an overview of the current status, indications, individual techniques, and future perspectives.

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.

"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.

Current surgical standards of care in Wilms tumor

BACKGROUND

Wilms tumor (WT) is the second most common abdominal tumor in children.

METHODS

This chapter discusses surgical considerations for the management of unilateral and bilateral WT.

RESULTS

Currently, survival exceeds 90%, owing to multicenter studies under the auspices of the Children's Oncology Group and Société Internationale d'Oncologie Pédiatrique. Surgical excision remains the mainstay of oncologic control and is also crucial for proper staging of disease in order to direct adjuvant therapy and limit treatment-related morbidity.

CONCLUSIONS

Careful attention must be paid to proper disease staging, upfront and adjuvant therapy, and surgical technique in order to optimize oncologic outcomes while minimizing short- and long-term morbidity.

The role of minimally invasive surgery in pediatric solid tumors

During recent years, minimally invasive surgery (MIS) has become the standard approach for various operations in infants and children. MIS in pediatric thoracic and abdominal tumors is a controversial approach in the surgical management of childhood cancer. Meanwhile, more and more oncological biopsies and resections are being performed laparoscopically or thoracoscopically. Despite its increasing role in pediatric tumor surgery, the different national and international multicenter trial groups have not yet implemented MIS within guidelines and recommendations in most of the current treatment protocols. An increasing number of retrospective reports describes a potential role of MIS in the management of different pediatric oncological entities. Over the time, there has been a diverse development of this approach with regard to the different neoplasms. Nevertheless, there is a lack of prospective randomized trails assessing MIS. This still represents a requirement for evidence-based medicine and judging the advantages and disadvantages of this approach. The purpose of this state-of-the-art article is to review the current literature to describe the application of MIS in pediatric solid tumors.

Minimally invasive surgery versus open surgery for the treatment of solid abdominal and thoracic neoplasms in children

BACKGROUND

Minimally invasive surgery (MIS) is an accepted surgical technique for the treatment of a variety of benign diseases. Presently, the use of MIS in patients with cancer is progressing. However, the role of MIS in children with solid neoplasms is less clear than it is in adults. Although the use of diagnostic MIS to obtain biopsy specimens for pathology is accepted in paediatric surgical oncology, there is limited evidence to support the use of MIS for the resection of malignancies. This review is the second update of a previously published Cochrane review.

OBJECTIVES

To ascertain differences in outcome between the minimally invasive and open surgical approaches for the treatment of solid intra-abdominal or intra-thoracic neoplasms in children. The primary outcomes of interest are OS, EFS, port-site metastases and recurrence rate; the secondary outcome of interest is surgical morbidity.

SEARCH METHODS

We searched CENTRAL (The Cochrane Library 2014, Issue 1), MEDLINE/PubMed (from 1966 to February 2014) and EMBASE/Ovid (from 1980 to February 2014) to identify relevant studies. In addition, we searched reference lists of relevant articles and reviews and the conference proceedings of the International Society for Paediatric Oncology and the American Society of Clinical Oncology from 2003 to 2013. On 1 May 2014 we scanned the ISRCTN Register (on www.controlled-trials.com), the National Institutes of Health register (on www.controlled-trials.com and www.clinicaltrials.gov) and the World Health Organization International Clinical Trials Registry Platform (on www.apps.who.int/trialsearch) for ongoing trials.

SELECTION CRITERIA

Randomised controlled trials (RCTs) or controlled clinical trials (CCTs) comparing MIS to open surgery for the treatment of solid intra-thoracic or intra-abdominal neoplasms in children (aged 0 to 18 years) were considered for inclusion.

DATA COLLECTION AND ANALYSIS

Two authors performed the study selection independently.

MAIN RESULTS

The literature search retrieved 542 references. After screening the titles and abstracts we excluded 534 references which clearly did not meet the inclusion criteria. We assessed eight full text studies for eligibility and all of these studies were excluded from the review because they were not RCTs or CCTs. These excluded studies included case series, retrospective chart reviews and retrospective cohort studies. The scanning of reference lists and conference proceedings did not identify any additional studies and no (ongoing trials) were identified by the searches of trial registries. No studies that met the inclusion criteria of this review were identified

AUTHORS' CONCLUSIONS

No RCTs or CCTs evaluating MIS for the treatment of solid intra-thoracic or intra-abdominal neoplasms in children could be identified. The current evidence base informing the use of MIS in children with solid abdominal and thoracic neoplasms is based on other study designs like case reports, retrospective chart reviews and cohort studies and should be interpreted with caution. Thus there is insufficient evidence to allow any definitive conclusions regarding the use of MIS in these patients. High quality RCTs comparing MIS to open surgery are required. To accomplish this, centres specialising in MIS in children should collaborate.

The current status of treatment of Wilms' tumor as per the SIOP trials

This paper attempts to briefly describe the International Society of Paediatric Oncology (SIOP) policy of treatment of nephroblastoma since first study (SIOP 1) launched in 1971 until today. It focuses on the advantages of the preoperative chemotherapy and the stratification of patients induced this way. Marked efficacy of the pretreatment opened the way for less aggressive surgical management also in case of the "so-called" regular unilateral cases: Nephron-sparing surgery and minimal invasive techniques will probably find its place in this field of pediatric surgical oncology; however, very careful selection of cases must be the priority.

Minimally invasive nephrectomy for Wilms tumors in children - data from SIOP 2001

PURPOSE

To analyse the surgical and oncological outcome of minimally invasive surgery (MIS) for tumor nephrectomy in Wilms tumor (WT) patients.

METHODS

WT patients from the SIOP 2001 trial, undergoing MIS for tumor nephrectomy were analyzed with regard to demographic characterization, surgical specifications, complications, and outcome.

RESULTS

There were 24 children matching the inclusion criteria. Median age at operation was 40.35 months (14.3-65.4). All patients received preoperative chemotherapy. Median tumor volume was 177.5 ml at diagnosis (46.5-958) and 73.0 ml at surgery (3.8-776). There was one surgical complication (splenic injury), no intraoperative tumor rupture occurred. Abdominal stage was I in 14, II in 7, and III in 3 patients. Adequate lymph node sampling was performed in only 2 patients. One local relapse occurred. Event-free survival was 23/24, overall survival was 24/24, median follow up was 47 months (2-114).

CONCLUSIONS

We present the largest series so far of minimally invasive nephrectomies for nephroblastoma based on a multinational trial. Treatment results were comparable to those of open surgery; however, experience of operating surgeons was generally high. Discipline of lymph node sampling was inadequate. Based on this analysis a prospective study on MIS in nephroblastoma is planned by the SIOP Renal Tumor Study Group.

Innovations in the management of Wilms' tumor

Advances in the management of Wilms' tumor have been dramatic over the past half century, not in small part due to the institution of multimodal therapy and the formation of collaborative study groups. While different opinions exist in the management of Wilms' tumors depending on where one lives and practices, survival rates have surpassed 90% across the board in Western societies. With more children surviving into adulthood, the concerns about morbidity have reached the forefront and now represent as much a consideration as oncologic outcomes these days. Innovations in treatment are on the horizon in the form of potential tumor markers, molecular biological means of testing for chemotherapeutic responsiveness, and advances in the delivery of chemotherapy for recurrent or recalcitrant tumors. Other technological innovations are being applied to childhood renal tumors, such as minimally invasive and nephron-sparing approaches. Risk stratification also allows for children to forego potentially unnecessary treatments and their associated morbidities. Wilms' tumor stands as a great example of the gains that can be made through protocol-driven therapy with strenuous outcomes analyses. These gains continue to spark interest in minimization of morbidity, while avoiding any compromise in oncologic efficacy. While excitement and innovation are important in the advancement of treatment delivery, we must continue to temper this enthusiasm and carefully evaluate options in order to continue to provide the highest standard of care in the management of this now highly curable disease.

Minimally invasive surgery in the management of abdominal tumors in children

The application of minimally invasive surgical techniques to pediatric abdominal tumors is a controversial application towards the surgical management of childhood cancer. Although general pediatric surgeons practice minimally invasive surgery techniques in a vast array of abdominal cases, its role in pediatric oncology is still developing, with no consensus in North America about its use for pediatric solid abdominal tumors. The purposes of this article are to review the current literature about the use of minimally invasive surgery in pediatric abdominal oncology and to examine established indications, procedures and technologic advances.

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

OBJECTIVES

To compare the outcomes of laparoscopic nephrectomy (LN) with open radical nephrectomy (ORN) in the management of consecutive pediatric neoplasms.

PATIENTS AND METHODS

Retrospective cohort study of consecutive children treated for primary renal tumors between 2006 and 2011, segregated based on surgical modality (LN/ORN). Pre-, intra- and postoperative data and outcomes were collected.

RESULTS

Demographics from the 45 patients (13 LN, 32 ORN) were similar, and tumors in the LN group were smaller [6.59 ± 1.8 cm vs. 10.99 ± 2.99 cm ORN (p < 0.05)]. Six patients had preoperative chemotherapy (two LN, four ORN). No tumor ruptures occurred with either technique. Wilms tumor (seven LN, 24 ORN) was the most common diagnosis, followed by renal cell carcinoma (four LN, four ORN). Procedure length was similar between groups (282 ± 79 LN, 263 ± 81 min ORN). Mean length of stay was significantly shorter for LN (2.9 vs. 5.9 days; p = 0.002). Postoperative narcotic requirements and use of nasogastric tube were higher in the ORN group. After a median follow-up of 18 (LN) and 33 months (ORN), 1 and 4 recurrences occurred, respectively.

CONCLUSIONS

LN is an attractive alternative to open surgery in carefully selected cases of pediatric renal tumors. Procedure length and incidence of intra-operative rupture were not increased, while post-operative recovery and hospital stay were shorter for LN. Longer follow-up is mandatory to confirm comparable oncological outcomes to ORN.

Laparoscopic treatment of renal cancer in children: a multicentric study and review of oncologic and surgical complications

OBJECTIVE

The aim was to report a multicentric study with a longer follow-up to evaluate the laparoscopic radical nephrectomy in children with renal cancer.

MATERIAL AND METHODS

This was a retrospective multicentric study, from October 2005 to January 2012, of children who underwent a laparoscopic radical nephrectomy for small renal malignant tumors.

RESULTS

Seventeen children were included in this study. Sixteen underwent chemotherapy before surgery according the SIOP (Société Internationale d'Oncologie Pédiatrique) protocol and one was treated by surgery only for a carcinoma. All except one could be treated by laparoscopy; the biggest tumoral size was 8 cm. The median hospital stay was 3 days (2-10). The pathologic examination showed 15 Wilms' tumors, one clear cell sarcoma and one TFE3 renal cell carcinoma. With a median follow-up of 42 months (range 12 and 77 months) after laparoscopic radical nephrectomy, 15 children had no oncological complications (port site or local recurrence, pulmonary metastasis) and one had a local recurrence without intraoperative tumoral rupture. The child with TFE3 renal cell carcinoma died 4 years after surgery from brain and lung metastases without local recurrence. No small bowel obstruction occurred.

CONCLUSIONS

Radical nephrectomy in children for Wilms' tumor or other renal cancer can be safely performed laparoscopically and our indications can be summarized, for trained laparoscopic surgeons, by small tumors under about 8 cm diameter, especially without crossing the lateral edge of the vertebra on the CT scan at the time of surgery.

Minimally invasive surgery for pediatric tumors - current state of the art

During recent years, minimally invasive surgery (MIS) has become the standard approach for various operations in infants and children. This also holds true for surgery in children with solid tumors. Meanwhile, more and more oncological biopsies and resections are being performed laparoscopically or thoracoscopically. Despite its increasing role in pediatric tumor surgery, the different national and international multicenter trial groups have not yet implemented MIS within guidelines and recommendations in most of the current treatment protocols. An increasing number of reports describe a potential role of MIS in the different entities of pediatric surgical oncology. Over the time, there has been a diverse development of this approach with regard to the different neoplasms. The aim of this article is to give an overview and to describe the current state of the art of MIS in pediatric solid tumors.

Minimally invasive nephron-sparing surgery for unilateral Wilms tumor

Minimally invasive surgery (MIS) for nephrectomy has been described since the early 1990s. More recently, MIS has been used for nephron-sparing surgery (NSS) when treating benign conditions. However, reports of NSS using MIS for malignant conditions are sparse. In this report, we describe our retroperitoneal laparoscopic approach for NSS for a localized Wilms tumor.

Wilms' tumor- roadmaps of management

The management of Wilms' tumor emerging of the outstanding clinical trials undertaken in the developed world in the last four decades has led to excellent longterm outcomes. The scenario in developing country like India is different; late presentation with massive tumors and advanced stage, lacunae in staging, nonavailability of pediatric medical oncologists and poor follow-ups are common. A comprehensive summary of available therapeutic modalities is provided here along with clear roadmaps of management of Wilms' tumor as per Société Internationale d'Oncologie Pédiatrique (SIOP) and National Wilms' Tumor Study Group/Children's Oncology Group (NWTSG/COG) protocols in simple tabulated form.

Minimally invasive surgery versus open surgery for the treatment of solid abdominal and thoracic neoplasms in children

BACKGROUND

Minimally invasive surgery (MIS) is an accepted surgical technique for the treatment of a variety of benign diseases. Presently, the use of MIS in patients with cancer is progressing. However, the role of MIS in children with solid neoplasms is less clear than it is in adults. Diagnostic MIS to obtain biopsy specimens for pathology has been accepted as a technique in paediatric surgical oncology, but there is limited experience with the use of MIS for the resection of malignancies.

OBJECTIVES

To ascertain the differences in outcome between the minimally invasive and open approach in the treatment of solid intra-thoracic and intra-abdominal neoplasms in children, regarding overall survival, event-free survival, port-site metastases, recurrence rate and surgical morbidity.

SEARCH METHODS

We searched the electronic databases of MEDLINE/PubMed (from 1966 to February 2011), EMBASE/Ovid (from 1980 to February 2011) and CENTRAL (The Cochrane Library 2011, Issue 1) with pre-specified terms. In addition, we searched reference lists of relevant articles and reviews, conference proceedings and ongoing trial databases.

SELECTION CRITERIA

Randomised controlled trials (RCTs) or controlled clinical trials (CCTs) comparing MIS and open surgery for the treatment of solid intra-thoracic or intra-abdominal neoplasms in children (aged 0 to 18 years).

DATA COLLECTION AND ANALYSIS

Two authors performed the study selection independently.

MAIN RESULTS

No studies that met the inclusion criteria of this review were identified.

AUTHORS' CONCLUSIONS

No RCTs or CCTs evaluating MIS in the treatment of solid intra-thoracic or intra-abdominal neoplasms in children could be identified, therefore no definitive conclusions could be made about the effects of MIS in these patients. Based on the currently available evidence we are not able to give recommendations for the use of MIS in the treatment of solid intra-thoracic or intra-abdominal neoplasms in children. More high quality studies (RCTs and/or CCTs) are needed. To accomplish this, centres specialising in MIS in children should collaborate.

Wilms tumor

Significant improvement has been made in the treatment of children with Wilms tumor. New protocols are in place designed to maintain a high rate of cure for these patients while minimizing toxicity, based on refinement of the risk-stratification system.

Scope and limitations of minimal invasive surgery in practice of pediatric surgical oncology

Management of Solid tumors in children needs a comprehensive multimodality protocol based treatment plan. Open surgical removal of the tumors occurring in any of the sites such as abdomen, thorax, chest wall, HFN (head, face, neck), brain and extremities, is the option which has been traditionally practiced even in the present era and in most of the centers. Nevertheless with the advances in science and technology and with ever increasing usage and expertise of laparoscopy in children, it's application has extended to treatment of solid tumors in children. A review of the scope of such intervention as well as the limitations of minimal invasive surgery in this specialized field of pediatric surgery has been attempted in this article.

Laparoscopic nephron-sparing resection of synchronous Wilms tumors in a case of hyperplastic perilobar nephroblastomatosis

Diffuse hyperplastic perilobar nephroblastomatosis (DHPLN) is a rare precursor lesion of Wilms tumor (WT). Because of the increased risk to develop WT in either kidney, current management algorithms of DHPLN merit nephron-sparing strategies, beginning with chemotherapy and close radiographic monitoring into late childhood. After resolution of DHPLN, subsequent detection of a renal nodule mandates resection to exclude WT. Here, we report the case of a 4-year-old girl who developed 2 synchronous nodules in the right kidney more than 2 years after completion of therapy for DHPLN. Because of the early detection and peripheral location of these 2 nodules, laparoscopic nephron-sparing resection of each was performed using ultrasonic dissection. Both nodules were determined on pathology to be favorable histology WT with negative surgical margins. The child was placed on vincristine and actinomycin D therapy for 18 weeks.

Peritoneal metastases after laparoscopic nephron-sparing surgery for localized Wilms tumor

A 2-year-old girl was referred for the management of the progression of her localized Wilms tumor. She had undergone laparoscopic nephron-sparing surgery for her right Wilms tumor 3 months earlier. Postoperative chemotherapy was commenced 6 weeks later. Subsequent computer tomographic evaluation 12 weeks postsurgery showed local recurrence and peritoneal tumors. These findings were confirmed at laparotomy. We report the first case of peritoneal tumor dissemination after laparoscopic nephron-sparing surgery for localized Wilms tumor.

Current management of wilms' tumor

Wilms' tumor is the most common malignant renal tumor in children. Survival has improved dramatically over time as a result of prospective randomized clinical trials conducted by the pediatric cooperative cancer groups. Current research is directed toward identifying low-risk patients for whom a reduction in treatment intensity would decrease long-term morbidity. This article reviews the most recent advances in the biology and treatment of children with Wilms' tumor.

Minimally invasive surgery versus open surgery for the treatment of solid abdominal and thoracic neoplasms in children

BACKGROUND

Minimally invasive surgery (MIS) is an accepted surgical technique for the treatment of a variety of benign diseases. Presently, the use of MIS in patients with cancer is progressing. However, the role of MIS in children with solid neoplasms is less clear than it is in adults. Diagnostic MIS to obtain biopsy specimens for pathology has been accepted as a technique in paediatric surgical oncology, but there is limited experience with the use of MIS for the resection of malignancies.

OBJECTIVES

To ascertain the differences in outcome between the minimally invasive and open approach in the treatment of solid intra-thoracic and intra-abdominal neoplasms in children, regarding overall survival, event-free survival, port-site metastases, recurrence rate and surgical morbidity.

SEARCH STRATEGY

We searched the electronic databases of MEDLINE/PubMed (from 1966 to March 2008), EMBASE/Ovid (from 1980 to March 2008) and CENTRAL (The Cochrane Library 2008, Issue 1) with pre-specified terms. In addition, we searched reference lists of relevant articles and reviews, conference proceedings and ongoing trial databases.

SELECTION CRITERIA

Randomised controlled trials (RCTs) or controlled clinical trials (CCTs) comparing MIS and open surgery for the treatment of solid intra-thoracic or intra-abdominal neoplasms in children (aged 0 to 18 years).

DATA COLLECTION AND ANALYSIS

Two authors performed the study selection independently.

MAIN RESULTS

No studies that met the inclusion criteria of this review were identified.

AUTHORS' CONCLUSIONS

No RCTs or CCTs evaluating MIS in the treatment of solid intra-thoracic or intra-abdominal neoplasms in children could be identified, therefore no definitive conclusions could be made about the effects of MIS in these patients. Based on the currently available evidence we are not able to give recommendations for the use of MIS in the treatment of solid intra-thoracic or intra-abdominal neoplasms in children. More high quality studies (RCTs and/or CCTs) are needed. To accomplish this, centres specialising in MIS in children should collaborate.