Minimally invasive nephron-sparing surgery for unilateral Wilms tumor

Nephron-sparing surgery in nonsyndromic unilateral wilms' tumor: An insight into the ongoing surgical controversy

Background:

Unilateral Wilms' tumor (uWT) is the most common renal malignancy in the pediatric population. Although the onset of surgical intervention like radical nephrectomy (RN) has substantially reduced the mortality rate, recent evidence has raised concerns regarding several postoperative complications associated with this procedure. Nephron-sparing surgery (NSS) has been reported to avoid such postoperative complications and have high technical success rate. However, not much literature is available comparing the efficacy of RN and NSS for managing nonsyndromic uWT, which makes it less acceptable globally.

Materials and Methods and Results:

A systematic identification of the literature was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines on four academic databases: MEDLINE, Scopus, EMBASE, and CENTRAL. Out of 1017 records, 20 manuscripts including 312 patients were included in the review; 4 patients treated by the author (unpublished data) have also been included. The studies included 7 retrospective case series with no comparison group, 4 retrospective case series with comparison group, 4 retrospective series with a cursory mention of NSS in uWT, 2 case reports, 1 protocolized prospective trial with comparison group, 1 administrative database analysis with comparison group, and 1 randomized controlled study. In all, 316 patients with nonsyndromic uWT were studied. The pretherapy volumes of the WT ranged from 2.4 to 640 ml. Majority of them were administered preoperative chemotherapy. About half of the patients (n = 159) (50.3%) were Stage I tumors. Stage II, III, and IV tumors were seen in 23 (7.3%), 20 (6.3%), and 3 (1%) patients. Stage was not specified in 111 (35.1%) patients. Majority of them were “intermediate risk” WT. All these tumors were nonanaplastic. Surgical margins were reported positive in 13 (4%) patients. Overall and event-free survivals were 100% in most of the studies; only handful of relapses were noted in this systematic review.

Conclusions:

This qualitative systematic review recommends the use of NSS for nonsyndromic uWT. The procedure accounts for higher postoperative renal function and lesser incidence of hypertension as compared to the radical nephrectomy. Overall and event-free survivals are comparable or even better with NSS.

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.

3D Model Facilitated Zero-Ischemia Laparoscopic Nephron Sparing Resection in Nephroblastomatosis Following the Addition of Cis-Retinoic Acid

There are limited reports of laparoscopic nephron sparing surgery (LNSS) in children and none where a 3D model facilitated oncological resection. There are also limited reports discussing the use of cis-retinoic acid in bilateral diffuse hyperplastic perilobar nephrogenic rests (DHPLNR). We report the first case of a 3D model facilitated zero-ischemia LNSS in children and the first following treatment with cis-retinoic acid. The patient was a 3-year-old girl with bilateral DHPLNR who had recurrent disease following standard therapy. She had suspicious lesions in the upper pole of the left kidney. Both were completely excised and histologically described as hyperplastic nephrogenic rests.

Robotic-assisted laparoscopic management of renal tumors in children: Preliminary results

AIM

We present the preliminary results of robotic-assisted laparoscopic (RAL) total and partial nephrectomy for renal malignant tumors in children.

METHODS

This is a prospective study of patients operated with RAL between December 2016 and September 2018. Patients with Wilms tumors were treated according to the SIOP-2001 protocol. Patient and tumor characteristics, type of surgery, surgical-related morbidity, and oncologic outcomes were recorded. Results were compared with a series of patients with similar age- and tumor-related characteristics operated during the same period by an open surgical approach.

RESULTS

Ten children underwent RAL nephrectomy with a mean age of five years (3.2-14.1 years). Total nephrectomy was done in six cases for Wilms tumor and in one case for renal sarcoma; three cases were converted. Complete removal of tumor without rupture was achieved in all cases. Postoperative course was uneventful, and patients were discharged between days 2 and 7. Neither recurrence nor medium-term complications occurred. Nine patients are alive with a median follow-up of 16 months (6-27 months) and one female died from complications of central nervous system metastases one year after surgery. When compared with the open surgical approach group, median tumor volume was smaller (P = 0.005), hospital stay was shorter (P = 0.01), and operative time was similar (P = 0.20).

CONCLUSIONS

RAL total and partial nephrectomy procedure for renal tumor in children may be an option in carefully selected cases. Indication should be discussed at tumor boards and surgery performed while adhering strictly to oncological surgical rules.

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.

Nephron-sparing surgery for Wilms tumor: A systematic review

INTRODUCTION

Radical nephrectomy (RN, or total nephrectomy) is the current gold-standard surgical treatment for children with Wilms tumors (WT). However, nephron-sparing surgery (NSS, or partial nephrectomy) has recently been gaining increasing attention. The objective of this systematic review is to compare the effectiveness of NSS as compared with RN for the treatment of children with WT.

METHODS

We searched the Cochrane Controlled Trials Register, clinicaltrials.gov, MEDLINE, EMBASE, Google Scholar, and recently presented meeting abstracts for reports in English. The bibliographies of included studies were then hand-searched for any missed articles. The protocol was prospectively registered. Manuscripts were assessed and data abstracted in duplicate with differences resolved by the senior author. Owing to high heterogeneity among the final included studies, only a qualitative systematic review was performed; no formal meta-analysis was undertaken.

RESULTS

We identified 694 articles, 118 of which were selected for full-text review and 66 of which were included in the final analysis. Most studies were single- or multi-institution retrospective case series (60, 91%), with a small number of prospective cohort studies (6, 9%) and 1 administrative database analysis. Most studies were from Europe (27, 41%) or North America (21, 32%). Nearly half (32, 48%) of studies those were included were dated from 2010 or later. In total, data on 4,002 patients were included, of whom 1,040 (26%) underwent NSS and 2,962 (74%) underwent NSS. Reported rupture rates were similar between RN and NSS (13% vs. 7%), as were recurrence rates (12% vs. 11%) and survival rates (85% vs. 88%). However, these comparisons are limited by inherent biases in the design and reporting of most included studies.

CONCLUSIONS

Most contemporary studies reporting the use of NSS in children with WT report similar long-term outcomes to RN. However, most existing studies are limited by their small numbers, inconsistent reporting, and methodological biases. There are significant opportunities for future research on the use of NSS in children with WT, including issues related to surgical quality, optimal technique, timing and duration of chemotherapy, and variation in the use of NSS among centers.

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.

NEPHRON-SPARING SURGERY FOR BILATERAL WILMS TUMOR

Synchronous bilateral disease occurs in approximately 5 % of children with Wilms tumor (WT), and is independently associated with an increased risk of renal insufficiency. Nephron-sparing surgery (NSS) allows preservation of renal mass and improved renal function. Published oncologic and functional outcomes with NSS to date are generally good, likely reflecting proper patient selection and excellent surgical technique during tumor excision, as well as appropriate use of upfront and adjuvant therapies. Here we highlight important issues regarding the use of NSS in children with bilateral Wilms tumor (BWT).

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 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.

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.

Oncology: the role of partial nephrectomy in Wilms tumor

Wilms tumor represents the most common pediatric renal malignancy and the fourth most common childhood cancer overall. Overall survival from Wilms tumor has increased to over 90 % secondary to multidisciplinary therapy and multi-institutional cooperative group trials. Recent therapeutic focus has shifted to reduction in treatment morbidity and renal preservation while maintaining the high survival rates. Partial nephrectomy is an integral component of the multimodal treatment protocols for Wilms tumor patients with bilateral disease, solitary kidney, or predisposing syndromes. Recent consideration has been given to utilization of nephron sparing surgery (NSS) in carefully selected patients with nonsyndromic unilateral Wilms tumor. While long-term, prospective data in this subgroup of patients is not yet available, case series demonstrate comparable oncologic outcomes after partial versus radical nephrectomy. The relative rarity of Wilms tumor, especially those amenable to upfront partial nephrectomy, presents a challenge to conducting controlled trials.