Indocyanine green-guided nephron-sparing surgery for pediatric renal tumors

Bilateral Wilms Tumour: Is Neoadjuvant Doxorubicin Necessary?

Approximately 5% to 8% of patients with Wilms tumour have bilateral disease. The prevalence of bilateral Wilms tumour (BWT) is higher in individuals with genetic predisposition syndromes than in those without. The goal of therapy is to preserve as much renal tissue as possible without compromising the overall oncological outcomes, utilising neoadjuvant chemotherapy followed by nephron sparing surgery (NSS) if possible. The Children's Oncology Group (COG) in North America and the International Society of Paediatric Oncology (SIOP) in Europe have developed the main protocols for the treatment of BWT. Both protocols are similar: initial biopsies are not indicated, and they both recommend surgical resection at week 6 or no later than week 12. Chemotherapy includes the use of vincristine and actinomycin-D in both protocols, but the COG approach also includes the use of doxorubicin, which is a cardiotoxic drug with important long-term effects on the cardiac function of childhood cancer survivors. What doxorubicin adds to patients with BWT in terms of radiological tumour response, resectability, long-term renal function and overall survival, is still not very well described and it may be variable depending on the tumour biology. This article describes the current approach for BWT in North America and Europe, focusing on the potential effect that doxorubicin may have on patient outcomes.

Nephron-sparing Surgery for Pediatric Renal Tumors After Centralization of Pediatric Oncology Care in the Netherlands: Improved Outcomes With 3D Modeling

BACKGROUND AND AIM

In this retrospective single center cohort study, we report the surgical outcomes of nephron-sparing surgery (NSS) for Wilms' tumor (WT) patients since centralization of pediatric oncology care in the Netherlands, and implementation of technological advancements. Therewith we describe the influence of experience and innovations for this type of surgery.

METHODS

We retrospectively assessed all NSS procedures from January 1st 2015 until January 1st 2024 for patients who underwent surgery for a renal tumor at the Princess Máxima Center for Pediatric Oncology. Data were gathered on patient characteristics, diagnostic information, radiological characteristics, surgical technique and use of innovations, postoperative outcome, administered treatment and surgical follow-up.

RESULTS

36 patients (58 % female, 42 % male) were included with a total of 43 NSS procedures. Mean (SD) age at diagnosis was 33.3 (23.1) months. 16 procedures were performed without 3D models, of which 3 (18.8 %) resulted in an unexpected positive margin. 27 procedures were preoperatively planned with a 3D model with one (3.7 %) unexpected anticipated positive margins (p = 0.101). Six (13.9 %) procedures had post-operative complications including five urine leakages, one chyle leakage and two (reversible) acute kidney insufficiency. Four patients received a re-intervention (JJ-stent or drain).

CONCLUSIONS

In this retrospective single center cohort study, we show a good surgical outcome after NSS for children with renal tumors after the implementation of 3D models. This study can act as a baseline cohort to harmonize preoperative assessment, intraoperative technique and implementation of innovative surgical technology for further expansion of NSS for WT patients.

Practical Guidelines for the Use of Indocyanine Green in Different Branches of Pediatric Surgery: A Polish Nationwide Multi-Center Retrospective Cohort Study

Background and Aim

Pediatric surgery requires high precision and safety due to children's unique anatomy and physiology. Innovations that enhance surgical precision, reduce operative time, and improve postoperative outcomes are invaluable. Indocyanine green (ICG), a near-infrared fluorescent dye, has received significant attention for its potential to address these needs. The study aimed to describe applications of ICH in pediatric surgery in Poland, provide evidence to support integration of ICG into pediatric surgical practice and evaluate the safety and feasibility of ICG.

Methods

Data were collected from the medical records of 136 patients undergoing surgical treatment in four leading pediatric surgical clinical centers in Poland. There are four main groups of surgical procedures: oncological, gastrointestinal, urological and lymphatic. Calculations were performed using Statistica 13 by TIBCO and PQStat v. 1.8.6.120 by PQStat Software. Additionally, descriptive statistics were performed.

Results

The efficacy and safety of ICG were confirmed in the entire study group. No complications were reported with the use of the indocyanine green. Exhaustive descriptive statistics presented key information on the use of ICG for each of the studied groups.

Conclusions

The study validates the efficacy and safety of ICG fluorescence imaging in pediatric surgery. By enhancing surgical precision and improving postoperative outcomes, ICG represents a significant advancement in pediatric surgical care. The establishment of standardized protocols and the emphasis on specialized training will be key to maximizing the benefits of ICG.

Novel Intraoperative Applications of Fluorescence Imaging Using Indocyanine Green in Pediatric Urology

PURPOSE OF REVIEW

Near-infrared fluorescence imaging (NIRF) with the use of indocyanine green (ICG) has been recently adopted in pediatric urology after its well-published use in the adult population. As a powerful tool that can help delineate complex anatomy and congenital anomalies, we discuss the various applications of this imaging in minimally invasive and open surgery in pediatric urology.

RECENT FINDINGS

The most reported applications of ICG in pediatric urology are within minimally invasive surgery, particularly varicoceles, renal surgery such as nephrectomies and renal tumor excision, mimicking its use in adult urology. ICG has also been applied to reconstructive urology such as ureteral reconstruction, hypospadias repair and bladder exstrophy. Despite its safety and more widespread use in pediatric surgery, all published studies in pediatric urology to date have been limited to small and single-center experiences, reflecting the novel nature of this technology in this field. ICG has been shown to be safe and effective in children, particularly in those with complex anatomy and in technically challenging surgeries. Future studies should focus on standardized protocols for children and multi-center comparative studies.

Optical imaging guidance in oncologic surgery and interventional oncology

Over recent decades, optical imaging (OI) has become an integral part of medical imaging, offering significant advantages over other modalities, such as computed tomography (CT) and magnetic resonance imaging (MRI). OI is distinguished by its real-time imaging capability, cost-effectiveness, portability, absence of ionizing radiation, and high patient acceptability. The introduction of advanced optical dyes (including FDA-approved agents like indocyanine green, Cytalux, and Gleolan) has greatly enhanced its clinical utility. OI has shown clear benefits in the management of patients with cancer, originally by open surgery and now extending to minimally invasive, image-guided interventional procedures. This review highlights recent developments in OI for oncology, emphasizing its benefits for clinicians in guiding surgical and interventional procedures.

Clinical Consensus Statement on the Use of Indocyanine Green Fluorescence-guided Surgery in Pediatric Patients

BACKGROUND AND AIMS

Indocyanine Green Fluorescence (ICG-F)- guided surgery is becoming an increasingly helpful tool in pediatric surgical care. This consensus statement investigates the utility of ICG-F in various pediatric surgical applications, primarily focusing on its evidence base, safety, indications, use across different surgical specialties and dosing strategies. The aim is to establish an international consensus for ICG-F use in pediatric surgery.

METHODS

An international panel of 15 pediatric surgeons from 9 countries was assembled. The structured process consisted of a rapid scoping review, iterative discussion sessions, mixed-methods studies with key stakeholders, and voting rounds on individual statements to create draft consensus statements.

RESULTS

100 articles were identified during the review and summarized by application. Based on this condensed evidence, consensus statements were generated after 3 iterative rounds of anonymous voting. Key areas of agreement were quality of evidence, the safety of ICG, pediatric surgical indications, utilization per surgical specialty, and dosing of ICG.

CONCLUSION

This consensus statement aims to guide healthcare professionals in managing ICG-F use in pediatric surgical cases based on the best available evidence, key stakeholder consultation, and expert opinions. Despite ICG-F's promising potential, the need for higher-quality evidence, prospective trials, and safety studies is underscored. The consensus also provides a framework for pediatric surgeons to utilize ICG-F effectively.

LEVEL OF EVIDENCE

III.

Utilization of Indocyanine Green (ICG) Fluorescence in Patients with Pediatric Colorectal Diseases: The Current Applications and Reported Outcomes

In pediatric colorectal surgery, achieving and visualizing adequate perfusion during complex reconstructive procedures are paramount to ensure postoperative success. However, intraoperative identification of proper perfusion remains a challeng. This review synthesizes findings from the literature spanning from January 2010 to March 2024, sourced from Medline/PubMed, EMBASE, and other databases, to evaluate the role of indocyanine green (ICG) fluorescence imaging in enhancing surgical outcomes. Specifically, it explores the use of ICG in surgeries related to Hirschsprung disease, anorectal malformations, cloacal reconstructions, vaginal agenesis, bladder augmentation, and the construction of antegrade continence channels. Preliminary evidence suggests that ICG fluorescence significantly aids in intraoperative decision-making by improving the visualization of vascular networks and assessing tissue perfusion. Despite the limited number of studies, initial findings indicate that ICG may offer advantages over traditional clinical assessments for intestinal perfusion. Its application has demonstrated a promising safety profile in pediatric patients, underscoring the need for larger, prospective studies to validate these observations, quantify benefits, and further assess its impact on clinical outcomes. The potential of ICG to enhance pediatric colorectal surgery by providing real-time, accurate perfusion data could significantly improve surgical precision and patient recovery.

Preoperative three-dimensional modelling and virtual reality planning aids nephron sparing surgery in a child with bilateral Wilms tumour

Bilateral Wilms tumour (BWT) is a surgically challenging condition. Virtual reality (VR) reconstruction aids surgeons to foresee the anatomy ahead of Nephron Sparing Surgery (NSS). Three-dimensional (3D) visualisation improves the anatomical orientation of surgeons performing NSS. We herewith report a case of BWT where VR planning and 3D printing were used to aid NSS. Conventional imaging is often found to be inadequate while assessing the tumour-organ-vascular anatomy. Advances like VR and 3D printing help surgeons plan better for complex surgeries like bilateral NSS. Next-generation extended reality tools will likely aid robotic-assisted precision NSS and improve patient outcomes.

Single-Plane Retroperitoneoscopic Adrenalectomy Guided by Indocyanine Green Dye: An Optimized Step

Background: The objective of this study was to explore the perioperative outcomes of single-plane posterior retroperitoneoscopic adrenalectomy (SPRA) guided by indocyanine green dye (ICG) fluorescence imaging. Methods: A retrospective analysis of patients who underwent SPRA from April to September 2023 in our center was conducted. Patients were divided into the ICG group and the non-ICG group, based on whether they received intraoperative ICG fluorescence guided or not. Baseline and perioperative data were recorded and analyzed by R software (R 4.3.1). Results: A total of 23 patients were enrolled in the study, with 12 in the ICG group and 11 in the non-ICG group. The demographics including age, gender, body mass index, or American Society of Anesthesiologists classification showed no significant differences between groups. There were obvious advantages in shortening adrenal gland localization time and total operative time, as well as reducing estimated blood loss in the ICG group compared with the non-ICG group (5.58 ± 0.36 minutes vs 7.55 ± 0.62 minutes, p < 0.001; 27.50 ± 5.46 minutes vs 45.00 ± 10.99 minutes, p < 0.001; 22.91 ± 7.57 mL vs 54.54 ± 18.90 mL, p < 0.001; respectively). Furthermore, patients in the ICG group exhibited significantly lower visual analog pain scale scores at 24 hours postoperatively and at discharge (p = 0.001 and p = 0.006, respectively). The oral intake intervals, hospital stays, and perioperative complications were comparable between groups. Conclusions: ICG-guided SPRA could be a safe and effective procedure for patients with adrenal tumors. This technique improves the accuracy and efficacy of adrenal gland localization and has shown benefits in perioperative outcomes. The use of ICG fluorescence guidance represents a promising clinical application.

Indocyanine green (ICG) fluorescence-enhanced applications in pediatric surgery

The breadth of pediatric surgical practice and variety of anatomic anomalies that characterize surgical disease in children and neonates require a unique level of operative mastery and versatility. Intraoperative navigation of small, complex, and often abnormal anatomy presents a particular challenge for pediatric surgeons. Clinical experience with fluorescent tissue dye, specifically indocyanine green (ICG), is quickly gaining widespread incorporation into adult surgical practice as a safe, non-toxic means of accurately visualizing tissue perfusion, lymphatic flow, and biliary anatomy to enhance operative speed, safety, and patient outcomes. Experience in pediatric surgery, however, remains limited. ICG-fluorescence guided surgery is poised to address the challenges of pediatric and neonatal operations for a growing breadth of surgical pathology. Fluorescent angiography has permitted intraoperative visualization of colorectal flap perfusion for complex pelvic reconstruction and anastomotic perfusion after esophageal atresia repair, while its hepatic absorption and biliary excretion has made it an excellent agent for delineating the dissection plane in the Kasai portoenterostomy and identifying both primary and metastatic hepatoblastoma lesions. Subcutaneous and intra-lymphatic ICG injection can identify iatrogenic chylous leaks and improved yields in sentinel lymph node biopsies. ICG-guided surgery holds promise for more widespread use in pediatric surgical conditions, and continued evaluation of efficacy will be necessary to better inform clinical practice and identify where to focus and develop this technical resource.

Surgery in Bilateral Wilms Tumor-A Single-Center Experience

The treatment of bilateral Wilms tumors (BWT) involves curing the cancer, preserving long-term renal function, and maintaining a good quality of life. Established methods for achieving these goals include preoperative chemotherapy and nephron-sparing surgery (NSS). This study aimed to evaluate the experience of a single institution in treating patients with BWT. We analyzed cases of BWT treated at the Pediatric Oncology Institute-GRAACC-Federal University of São Paulo over a period of 35 years. Bleeding control was performed with manual compression of the renal parenchyma. Thirty-three patients were included in the study. Thirty cases were synchronous tumors. The mean age at diagnosis was 30.4 months (±22 m) and 66.7% were girls. The median follow-up period was 83 months. Neoadjuvant chemotherapy was the primary approach in most patients (87.9%), with a simultaneous upfront surgical approach performed in 84.8%. Most patients underwent bilateral NSS (70.4%). There were no early complications in this series, but 39.4% had clinical complications. The five-year survival rate was 76%. Therefore, it is clear that the surgical approach to BWT plays a crucial role in achieving good outcomes. However, it is difficult to standardize surgical techniques and technology may have the potential to enhance safety.

Identification of Pediatric Tumors Intraoperatively Using Indocyanine Green (ICG)

BACKGROUND

Fluorescence-guided surgery (FGS) with indocyanine green (ICG) is increasingly applied in pediatric surgical oncology. However, FGS has been mostly reported in case studies of liver or renal tumors. Applying novel technologies in pediatric surgical oncology is more challenging than in adult surgical oncology due to differences in tumor histology, biology, and fewer cases. No consensus exists on ICG-guided FGS for surgically managing pediatric solid tumors. Therefore, we reviewed the literature and discuss the limitations and prospects of FGS.

METHODS

Using PRISMA guidelines, we analyzed articles on ICG-guided FGS for childhood solid tumors. Case reports, opinion articles, and narrative reviews were excluded.

RESULTS

Of the 108 articles analyzed, 17 (14 retrospective and 3 prospective) met the inclusion criteria. Most (70.6%) studies used ICG to identify liver tumors, but the timing and dose of ICG administered varied. Intraoperative outcomes, sensitivity and specificity, were reported in 23.5% of studies. Fluorescence-guided liver resections resulted in negative margins in 90-100% of cases; lung metastasis was detected in 33% of the studies. In otolaryngologic malignancies, positive margins without fluorescence signal were reported in 25% of cases. Overall, ICG appeared effective and safe for lymph node sampling and nephron-sparing procedures.

CONCLUSIONS

Despite promising results from FGS, ICG use varies across the international pediatric surgical oncology community. Underreported intraoperative imaging outcomes and the diversity and rarity of childhood solid tumors hinder conclusive scientific evidence supporting adoption of ICG in pediatric surgical oncology. Further international collaborations are needed to study the applications and limitations of ICG in pediatric surgical oncology.

Feasibility of indocyanine green-guided localization of pulmonary nodules in children with solid tumors

BACKGROUND

Clearing all pulmonary metastases is essential for curing pediatric solid tumors. However, intraoperative localization of such pulmonary nodules can be challenging. Therefore, an intraoperative tool that localizes pulmonary metastases is needed to improve diagnostic and therapeutic resections. Indocyanine green (ICG) real-time fluorescence imaging is used for this purpose in adult solid tumors, but its utility in pediatric solid tumors has not been determined.

METHODS

A single-center, open-label, nonrandomized, prospective clinical trial (NCT04084067) was conducted to assess the ability of ICG to localize pulmonary metastases of pediatric solid tumors. Patients with pulmonary lesions who required resection, either for therapeutic or diagnostic intent, were included. Patients received a 15-minute intravenous infusion of ICG (1.5 mg/kg), and pulmonary metastasectomy was performed the following day. A near-infrared spectroscopy iridium system was optimized to detect ICG, and all procedures were photo-documented and recorded.

RESULTS

ICG-guided pulmonary metastasectomies were performed in 12 patients (median age: 10.5 years). A total of 79 nodules were visualized, 13 of which were not detected by preoperative imaging. Histologic examination confirmed the following histologies: hepatoblastoma (n = 3), osteosarcoma (n = 2), and one each of rhabdomyosarcoma, Ewing sarcoma, inflammatory myofibroblastic tumor, atypical cartilaginous tumor, neuroblastoma, adrenocortical carcinoma, and papillary thyroid carcinoma. ICG guidance failed to localize pulmonary metastases in five (42%) patients who had inflammatory myofibroblastic tumor, atypical cartilaginous tumor, neuroblastoma, adrenocortical carcinoma, or papillary thyroid carcinoma.

CONCLUSIONS

ICG-guided identification of pulmonary nodules is not feasible for all pediatric solid tumors. However, it may localize most metastatic hepatic tumors and high-grade sarcomas in children.

Clinical application of indocyanine green fluorescence imaging navigation for pediatric renal cancer

Background

Indocyanine Green (ICG) fluorescence imaging has been widely used in the surgical treatment of adult renal cancers, but its application in pediatric renal cancers has rarely been reported. This study aims to summarize the experience of ICG fluorescence imaging in pediatric renal cancers and explores its safety and feasibility.

Methods

The clinical features, surgical information, ICG administration regimen, near infrared radiography data in vivo and ex vivo and pathological results of children with renal cancers using ICG navigation were analyzed and summarized.

Results

There were 7 cases of renal cancer, including 4 cases of Wilms tumor (WT), 1 case of malignant rhabdoid tumor of the kidney (MRTK) and 2 cases of renal cell carcinoma (RCC). By intraoperative intravenous injection of ICG from 2.5 to 5 mg (0.05-0.67 mg/kg), the tumors were visualized in 6 cases in vivo or ex vivo, and the tumor visualization failed in 1 case due to renal artery embolization before operation. By injecting 5 mg ICG into the normal renal tissue during the operation, 3 patients achieved fluorescent localization of sentinel lymph nodes. No ICG-related adverse reactions were found in any of the patients during or after operation.

Conclusions

ICG fluorescence imaging is safe and feasible for renal cancers in children. Intraoperative administration can achieve tumor and sentinel lymph node visualization which will facilitate the development of nephron sparing surgery (NSS). However, the technique is affected by ICG dose, anatomical conditions around the tumor, and renal blood flow. A proper dose of ICG and the complete removal of perirenal fat are helpful for the fluorescence imaging of the tumor. It has potential in the operation of renal cancer in children.

Evaluating the Development Status of Fluorescence-Guided Surgery (FGS) in Pediatric Surgery Using the Idea, Development, Exploration, Assessment, and Long-Term Study (IDEAL) Framework

Fluorescence-guided surgery (FGS) is used in many pediatric subspecialties but there are currently no standard guidelines or outcome data. We aimed to assess the current status of FGS in pediatrics using the Idea, Development, Exploration, Assessment, and Long-term study (IDEAL) framework. Clinical papers on FGS in children published from January 2000 to December 2022 were systematically reviewed. The stage of research development was measured considering seven fields of application: biliary tree imaging, vascular perfusion for gastrointestinal procedures, lymphatic flow imaging, tumor resection, urogenital surgery, plastic surgery, and miscellaneous procedures. Fifty-nine articles were selected. For each field of application, the overall IDEAL stage was determined to be 2a for biliary tree imaging (10 publications, 102 cases), 1 for vascular perfusion for gastrointestinal procedures (8 publications, 28 cases), 1 for lymphatic flow imaging (12 publications, 33 cases), 2a for tumor resection (20 publications, 238 cases), 2a for urogenital surgery (9 publications, 197 cases), and 1-2a for plastic surgery (4 publications, 26 cases). One report did not belong to any categories. FGS in children is still in an early phase of adoption and development. We recommend using the IDEAL framework as a guide and suggest developing multicenter studies to define the standard guidelines, effectiveness, and outcomes.

Nephron-sparing surgery for Wilms tumor

The algorithm that has been used successfully in the surgical management of unilateral Wilms tumor, radical nephroureterectomy, cannot be used in children who present with synchronous bilateral renal masses. Instead, a surgical approach that removes all tumor masses while preserving as much normal renal parenchyma as possible is encouraged to avoid acute and long-term renal insufficiency. We will review technical aspects of the conduct of nephron-sparing surgery for synchronous bilateral Wilms tumor, including the more recent advances in the use of imaging adjuncts such as pre-operative 3D imaging and fluorescence-guided surgery. The potential role of nephron-sparing surgery for unilateral Wilms tumor will also be discussed.

Fluorescence-Guided Surgery and Novel Innovative Technologies for Improved Visualization in Pediatric Urology

Fluorescence-guided surgery (FGS), three-dimensional (3D) imaging technologies, and other innovative devices are rapidly revolutionizing the field of urology, providing surgeons with powerful tools for a more complete understanding of patient-specific anatomy. Today, several new intraoperative imaging technologies and cutting-edge devices are available in adult urology to assist surgeons in delivering personalized interventions. Their applications are also gradually growing in general pediatric surgery, where the detailed visualization of normal and pathological structures has the potential to significantly minimize perioperative complications and improve surgical outcomes. In the field of pediatric urology, FGS, 3D reconstructions and printing technologies, augmented reality (AR) devices, contrast-enhanced ultrasound (CEUS), and intraoperative magnetic resonance imaging (iMRI) have been increasingly adopted for a more realistic understanding of the normal and abnormal anatomy, providing a valuable insight to deliver customized treatments in real time. This narrative review aims to illustrate the main applications of these new technologies and imaging devices in the clinical setting of pediatric urology by selecting, with a strict methodology, the most promising articles published in the international scientific literature on this topic. The purpose is to favor early adoption and stimulate more research on this topic for the benefit of children.