Indocyanine Green-Guided Pediatric Tumor Resection: Approach, Utility, and Challenges

Pediatric Adrenocortical Carcinoma: The Nuts and Bolts of Diagnosis and Treatment and Avenues for Future Discovery

Adrenocortical tumors (ACTs) are infrequent neoplasms in children and adolescents and are typically associated with clinical symptoms reflective of androgen overproduction. Pediatric ACTs typically occur in the context of a germline TP53 mutation, can be cured when diagnosed at an early stage, but are difficult to treat when advanced or associated with concurrent TP53 and ATRX alterations. Recent work has demonstrated DNA methylation patterns suggestive of prognostic significance. While current treatment standards rely heavily upon surgical resection, chemotherapy, and hormonal modulation, small cohort studies suggest promise for multi-tyrosine kinases targeting anti-angiogenic pathways or immunomodulatory therapies. Future work will focus on novel risk stratification algorithms and combination therapies intended to mitigate toxicity for patients with perceived low-risk disease while intensifying therapy or accelerating discoveries aimed at improving survival for patients with difficult-to-treat disease.

Surgical management of liver tumors

Two percent of pediatric malignancies arise primarily in the liver; roughly 60% of these cancers are hepatoblastoma (HB). Despite the rarity of these cases, international collaborative efforts have led to the consistent histological classification and staging systems, which facilitate ongoing clinical trials. Other primary liver malignancies seen in children include hepatocellular carcinoma (HCC) with or without underlying liver disease, fibrolamellar carcinoma (FLC), undifferentiated embryonal sarcoma of the liver (UESL), and hepatocellular neoplasm not otherwise specified (HCN-NOS). This review describes principles of surgical management of malignant pediatric primary liver tumors, within the context of comprehensive multidisciplinary care.

The Shared Ovary: A Multidisciplinary Discussion With Pediatric and Adolescent Gynecology

Pediatric and adolescent ovarian lesions are common and are frequently managed by both pediatric surgeons and pediatric and adolescent gynecologists. During the 2023 American Academy of Pediatric Section on Surgery meeting, an educational symposium was delivered focusing on various aspects of management of pediatric and adolescent benign and malignant masses, borderline lesions, and fertility options for children and adolescents undergoing cancer therapies. This article highlights the discussion during this symposium.

Utility of Indocyanine Green for Sentinel Lymph Node Biopsy in Pediatric Sarcoma and Melanoma

BACKGROUND

Indocyanine green (ICG) is a fluorescent dye with increasing use for adult sentinel lymph node biopsy (SLNB). The utility of ICG in pediatric oncology remains understudied. We aim to describe our experience using ICG for SLNB in pediatrics versus standard blue dye.

METHODS

A retrospective review of pediatric patients with melanoma or sarcoma who underwent SLNB with technetium plus ICG or blue dye from 2014 to 2023 at a large academic children's hospital was conducted.

RESULTS

Twenty-four patients were included; 58.3% were male with median age 13 years (range 4-21 years). The majority had a melanocytic tumor (91.7%) and 8.3% had sarcoma. All patients received technetium with concomitant blue dye (62.5%) or ICG (37.5%). ICG more reliably identified radioactive SLNs, compared to blue dye (mean 100% vs 78.3 ± 8.3%, p = 0.03). There was no significant difference in median operative time (ICG 82 min [68-203] vs blue dye 93 min [78-105], p = 0.84). Seven patients had positive SLNs (29.2%), with recurrence in 2 patients (8.3%) and 1 death (4.2%). There were no adverse events.

CONCLUSION

ICG-directed SLNB in children is a safe and effective alternative to blue dye. Use of ICG did not add to operative time, and more often identified sentinel nodes versus blue dye.

TYPE OF STUDY

Original Research Article, Retrospective Comparative Study.

LEVEL OF EVIDENCE

III.

Enhancing surgical planning for abdominal tumors in children through advanced 3D visualization techniques: a systematic review of future prospects

Introduction

Preoperative three-dimensional (3D) reconstruction using sectional imaging is increasingly used in challenging pediatric cases to aid in surgical planning. Many case series have described various teams' experiences, discussing feasibility and realism, while emphasizing the technological potential for children. Nonetheless, general knowledge on this topic remains limited compared to the broader research landscape. The aim of this review was to explore the current devices and new opportunities provided by preoperative Computed Tomography (CT) scans or Magnetic Resonance Imaging (MRI).

Methods

A systematic review was conducted to screen pediatric cases of abdominal and pelvic tumors with preoperative 3D reconstruction published between 2000 and 2023.

Discussion

Surgical planning was facilitated through virtual reconstruction or 3D printing. Virtual reconstruction of complex tumors enables precise delineation of solid masses, formulation of dissection plans, and suggests dedicated vessel ligation, optimizing tissue preservation. Vascular mapping is particularly relevant for liver surgery, large neuroblastoma with imaging-defined risk factors (IDRFs), and tumors encasing major vessels, such as complex median retroperitoneal malignant masses. 3D printing can facilitate specific tissue preservation, now accessible with minimally invasive procedures like partial nephrectomy. The latest advancements enable neural plexus reconstruction to guide surgical nerve sparing, for example, hypogastric nerve modelling, typically adjacent to large pelvic tumors. New insights will soon incorporate nerve plexus images into anatomical segmentation reconstructions, facilitated by non-irradiating imaging modalities like MRI.

Conclusion

Although not yet published in pediatric surgical procedures, the next anticipated advancement is augmented reality, enhancing real-time intraoperative guidance: the surgeon will use a robotic console overlaying functional and anatomical data onto a magnified surgical field, enhancing robotic precision in confined spaces.

What is the diagnostic accuracy of fluorescence-guided surgery for margin assessment in appendicular bone and soft tissue tumors? - A systematic review of clinical studies

BACKGROUND

Fluorescence-guided surgery (FGS) is a novel technique to successfully assess surgical margins intraoperatively. Investigation and adoption of this technique in orthopaedic oncology remains limited.

METHODS

The PRISMA guidelines were followed for this manuscript. Our study was registered on PROSPERO (380520). Studies describing the use of FGS for resection of bone and soft tissue sarcomas (STS) on humans were included. Diagnostic performance metrics (sensitivity, specificity, positive predictive value [PPV], negative predictive value [NPV] and accuracy) and margin positivity rate were the outcomes assessed.

RESULTS

Critical appraisal using the Joanna Brigs Institute checklists showed significant concerns for study quality. Sensitivity of FGS ranged from 22.2 % to 100 % in three of the four studies assessing his metrics; one study in appendicular tumors in the pediatric population reported 0 % sensitivity in the three cases included. Specificity ranged from 9.38 % to 100 %. PPV ranged from 14.6 % to 70 % while NPV was between 53.3 % and 100 %. The diagnostic accuracy ranged from 21.62 % to 92.31 %. Margin positivity rate ranged from 2 % to 50 %, with six of the seven studies reporting values between 20 % and 50 %.

CONCLUSIONS

FSG is a feasible technique to assess tumor margins in bone and STS. Reported performance metrics and margin positivity rates vary widely between studies due to low study quality and high heterogeneity in dying protocols.

LEVEL OF EVIDENCE

Level III, diagnostic study.

The Role of Indocyanine Green in Pediatric Gastrointestinal Surgery: Systematic Review

The use of near-infrared fluorescence imaging with indocyanine green (ICG) is actually considered as a very useful tool in decision-making strategy during challenging surgical procedures with a growing evidence in the literature. Our aim is to perform a systematic review focusing on ICG applications in gastrointestinal surgery. We conducted a systematic review with narrative synthesis in conformity with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines using PubMed, Medline, and EMBASE databases to identify articles describing the gastrointestinal perioperative use of ICG in children. We extracted data on study design, demographics, surgical indications, ICG dose, and perioperative outcomes. Eleven articles, including 94 pediatric patients, from 2013 to 2022 met the inclusion criteria for narrative synthesis in our systematic review, of which 6/11 (54.5%) were case reports, 4/11 (36.4%) were retrospective studies, and 1/11 (0.1%) were case series. Current clinical applications of ICG in gastrointestinal pediatric surgery included: esophagogastric surgery in 4/11 articles (36.4%), intestinal and pancreatic surgery in 3/11 articles (27.2%), and colorectal surgery in 4/11 articles (36.4%). ICG fluorescence in gastrointestinal pediatric surgery is a promising and safe technology that facilitates intraoperative localization of anatomical structures to achieve a more precise dissection and avoid injury to other adjacent tissues. It can be considered as a meaningful tool for assessing intestinal viability, as it provides objective data on tissue perfusion, and can impact the intraoperative decision in reconstructive surgeries requiring anastomosis. Future studies are needed to confirm these initial promising results. The lack of comparative and prospective studies is still the main limitation.

Robotic-assisted surgery for gynecological indications in children and adolescents: European multicenter report

Robotic-assisted surgery (RAS) is increasingly adopted in the pediatric population. This retrospective multicenter study aimed to report application of RAS for gynecological indications in pediatric patients. The medical records of all girls with gynecological pathology, operated in 4 different institutions over a 3-year period, were retrospectively collected. Robot docking time, total operative time, length of stay (LOS), requirement time of pain medication, complication rate, conversion rate, and pathology were analyzed. Twenty-three girls, with median age of 12.3 years (range 0.6-17.8) and median weight of 47.2 kg (range 9-73), received the following RAS procedures: ovarian cystectomy for ovarian cyst/mass (n = 10), salpingo-oophorectomy for ovarian complex mass (n = 6), bilateral gonadectomy for Turner syndrome SRY + (n = 1), salpingectomy for fallopian tube lesion (n = 1), paratubal cyst excision (n = 1), Gartner cyst excision (n = 1), paravaginal ganglioneuroma resection (n = 1), fistula closure in urogenital sinus (n = 1), and vaginoplasty using ileal flap in cloaca malformation (n = 1). Median operative time was 144.9 min (range 64-360), and median docking time was 17.3 min (range 7-50). Conversion to open or laparoscopy was not necessary in any case. Median LOS was 2.1 days (range 1-7), and median analgesic requirement was 2.2 days (range 1-6). One patient (4.3%) needed redo-surgery for recurrent Gartner cyst (Clavien 3b). This preliminary experience showed that RAS is safe and feasible for surgical treatment of gynecological pathology in pediatric patients, although no conclusive data are available to confirm its superiority over traditional laparoscopy. Randomized, prospective, comparative studies are needed to identify the gold standard approach for such indication.

Current trends and prospects of surgical techniques for hepatoblastoma

Hepatoblastoma, a common extracranial malignant solid tumor in childhood, is often detected at an advanced stage and is difficult to treat surgically. Despite the availability of multiple comprehensive treatments that can be combined with surgery, hepatoblastoma treatment outcomes remain poor. Surgery is the main treatment strategy for hepatoblastoma, but it faces many challenges, including tumor attachment to surrounding tissues, tumor wrapping or invading of vital organs and tissues, the presence of giant or multiple tumors, distant metastasis, the formation of a tumor thrombus, and significant surgical trauma. In this review, we discuss recent research advances and propose potential strategies for overcoming these challenges. Such strategies may improve the rate of hepatoblastoma resection and local control in children, as well as reduce complications and trauma.

Indocyanine Green (ICG) Fluorescence-Assisted Open Surgery Using the Rubina® Lens System in the Pediatric Population: A Single-Center Prospective Case Series

INTRODUCTION

There are scarce papers about the use of fluorescence-guided surgery (FGS) in the open surgical field. This study aimed to assess the usefulness of FGS in an open setting in the pediatric population and to report our preliminary experience using the Rubina® Lens system.

METHODS

All patients undergoing ICG fluorescence-assisted open surgery over the period September 2022-September 2023 were enrolled. Each surgical procedure was performed using the Rubina® Lens for ICG fluorescence visualization.

RESULTS

A total of 25 patients, 14 boys and 11 girls with a median age at surgery of 5.8 years-old (range 0-15), were enrolled. Surgical indications were dermoid/epidermoid cysts of the head (n = 7), lymphangiomas of the head/neck (n = 2), thyroglossal duct cysts (n = 7), gynecomastia (n = 3), preauricular fistula (n = 2), second branchial cleft fistula (n = 1), fibrolipoma of the shoulder (n = 1) and myofibroma of the gluteal/perineal region (n = 2). In all procedures, an intralesional injection of 2.5 mg/mL ICG solution using a 30-gauge needle was administered. No adverse reactions to ICG occurred. Median operative time was 68.6 min (range 35-189). The visualization of ICG-NIRF with the Rubina® Lens was achieved in all cases. No intraoperative complications were reported. Postoperative complications occurred in 3/25 patients (12%), with gynecomastia (n = 1), thyroglossal duct cyst (n = 1) and neck lymphangioma (n = 1), who developed a fluid collection in the surgical site, requiring needle aspiration in outpatient care (Clavien-Dindo 2). Complete mass excision was confirmed with pathology reports.

CONCLUSIONS

Based on this initial experience, FGS using the Rubina® Lens was very helpful in open surgery, providing enhanced visualization of anatomy and identification of margins, real-time reliability and low complication rate. It was easy to use, time saving, feasible and clinically safe. Previous experience in MIS is necessary to adopt this technology. The accuracy of the injection phase is important to avoid diffusion of the ICG into the perilesional tissue.

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.

Applications of indocyanine green (ICG) fluorescence technology in open surgery: preliminary experience in pediatric surgery

Background

Indocyanine green fluorescence technology (ICG) in pediatric minimally invasive surgery has undergone an important improvement in the last 5 years. However, its use in open surgery is still limited. In this paper, we aim to report our preliminary experience with Rubina® lens ICG fluorescence technology in combination with the IMAGE1 S™ system from KARL STORZ in open excision of masses in children.

Methods

The records of 18 patients undergoing open surgery for head, neck and thorax masses between September and November 2022 were retrospectively reviewed. Rubina® lens ICG fluorescence technology system was used in all the cases. In 10 cases we adopted the holding arm system and in 8 cases the hand-held technique. Data about patients' demographics, surgery and outcomes were collected and analyzed through the following criteria: mass localization, intraoperative time (min), ICG administration (ml), intraoperative complications, postoperative complications.

Results

A total of 18 patients were operated: 4 thyroglossal duct cysts, 3 supraorbital cysts, 2 neck masses, 2 pre-auricular and 2 scalp cysts, 2 gynecomastias, 2 lymphangiomas, 1 nose mass. In all the cases, intralesional injection of 0.5-1 ml of ICG solution was performed peri-operatively. Mean operative time was 58.4 min (35-134 min). Postoperative complications included seroma formation in 2 cases. Surgical pathology reports confirmed complete mass excision in all the cases.

Conclusion

Based on our preliminary experience, ICG fluorescence guided surgery using Rubina® lens system was very helpful also in open surgery procedures. Rubina® lens system permits to have a very low complication rate, a time-saving surgery, a real time reliability of anatomic structures and an excellent clinical safety. In our experience, holding arm system seems more comfortable than hand-held system. However, further cases need to be performed to evaluate the exact role and to identify new indications of this technique in open pediatric surgical procedures.

Laser speckle contrast imaging compared with indocyanine green in renal perfusion of a porcine model

Background

When viewed under near-infrared light, indocyanine green (ICG) signal for kidney perfusion can be utilized in partial nephrectomy. Laser speckle contrast imaging (LSCI) uses coherent light to detect perfusion during real-time laparoscopic surgery.

Materials and methods

Laser speckle contrast imaging or ActivSight, an imaging sensor adapter, was used during laparoscopy of an anesthetized porcine kidney model. ActivSight's "perfusion mode" and "quantification mode" displayed the blood flow as a heatmap and numerical signal intensity, respectively.

Results

After the upper segmental renal artery was clamped, ICG was seen in the lower pole, and LSCI showed low unit (dark color) quantification and perfusion in the upper pole. Indocyanine green was retained in the lower pole after the upper segmental artery was unclamped, and LSCI perfusion was demonstrated in the entire kidney.

Conclusions

Laser speckle contrast imaging is a dye-free, repeatable, real-time adjunct for renal parenchymal perfusion assessment applicable to minimally invasive renal surgery to complement the technology of ICG near-infrared fluorescence and advance digital surgery.

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.

Fluorescence-guided surgery: National trends in adoption and application in pediatric surgery

BACKGROUND

Fluorescence-guided surgery (FGS) with indocyanine green (ICG) is a rapidly diffusing surgical innovation, but its utilization in pediatrics remains unknown. We present a cross-sectional descriptive analysis of trends from a national database.

METHODS

The Pediatric Health Information System (PHIS) database was queried for patient encounters between January 2016 and July 2021 with an associated ICG administration within 3 days prior to surgery. All procedure codes from each encounter were reviewed by two surgeons to determine the most likely associated FGS procedure and assign an operative category.

RESULTS

1270 encounters were identified from 38 participating hospitals. The mean patient age (SD) was 8.3 (6.4) years, 54.5% were male, 63.8% were white, and 30.1% were Hispanic. The most common categories for ICG use were neurosurgery (21.3%), biliary (18.3%), perfusion (14.8%), urology (12.5%), gastrointestinal (10.8%), ophthalmology (8.8%), and thoracic (5.6%). Utilization over time increased for some categories (thoracic, visceral perfusion, and neurological procedures) or remained stable for other categories. Overall ICG utilization has increased in 2020 (n = 314) compared to 2016 (N = 83). The number of centers utilizing ICG has also increased from 14 hospitals in 2016 to 29 hospitals in 2020 though adoption remains unevenly distributed, with 5 high-utilization hospitals accounting for 56.8% of all ICG FGS cases.

CONCLUSION

ICG is being used across a wide variety of pediatric surgical disciplines. Trends over time show increasingly frequent adoption across the country, with a few high-volume centers driving the innovation. Fluorescence-guided surgery is commercially available and is becoming more commonplace for pediatric surgeons. Dedicated efforts will now be needed to assess outcomes using this promising technology.

LEVEL OF EVIDENCE

Level IV.

STUDY TYPE

Retrospective study.

Technical advances in the surgical management of Wilms tumors in children

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

Intraoperative Fluorescein Sodium in Pediatric Neurosurgery: A Preliminary Case Series from a Singapore Children’s Hospital

(1) Background: Fluorescein sodium (Na-Fl) has been described as a safe and useful neurosurgical adjunct in adult neurooncology. However, its use has yet to be fully established in children. We designed a study to investigate the use of intraoperative Na-Fl in pediatric brain tumor surgery. (2) Methods: This is a single-institution study for pediatric brain tumor patients managed by the Neurosurgical Service, KK Women’s and Children’s Hospital. Inclusion criteria consists of patients undergoing surgery for suspected brain tumors from 3 to 19 years old. A predefined intravenous dose of 2 mg/kg of 10% Na-Fl is administered per patient. Following craniotomy, surgery is performed under alternating white light and YELLOW-560 nm filter illumination. (3) Results: A total of 21 patients with suspected brain tumours were included. Median age was 12.1 years old. For three patients (14.3%), there was no significant Na-Fl fluorescence detected and their final histologies reported a cavernoma and two radiation-induced high grade gliomas. The remaining patients (85.7%) had adequate intraoperative fluorescence for their lesions. No adverse side effects were encountered with the use of Na-Fl. (4) Conclusions: Preliminary findings demonstrate the safe and efficacious use of intraoperative Na-Fl for brain tumors as a neurosurgical adjunct in our pediatric patients.

Utilization of robotics in pediatric surgical oncology

Despite increasing implementation of robotic surgery and minimally invasive techniques within adult surgical oncology and pediatric general surgery, the utilization of robotic-assisted resections for pediatric tumors has been met with controversy. The robotic platform affords numerous advantages over conventional surgical techniques. However, limited data and guidelines regarding patient selection, indications for the robotic approach, and long-term oncologic outcomes have delayed the widespread adoption of robotic-assisted resection of pediatric tumors. This paper reviews the benefits, limitations, and existing guidelines and data regarding the utilization of robotics in pediatric surgical oncology.

Intraoperative Evaluation of Soft Tissue Sarcoma Surgical Margins with Indocyanine Green Fluorescence Imaging

Soft tissue sarcomas (STS) are rare malignant tumors often associated with poor outcomes and high local recurrence rates. Current tools for intraoperative and definitive margin assessment include intraoperative frozen section and permanent pathology, respectively. Indocyanine green dye (ICG) is a historically safe fluorophore dye that has demonstrated efficacy for intraoperative margin assessment in the surgical management of both breast and gastrointestinal cancers. The utility of ICG in the surgical management of sarcoma surgery has primarily been studied in pre-clinical mouse models and warrants further investigation as a potential adjunct to achieving negative margins. This study is a prospective, non-randomized clinical study conducted on patients with confirmed or suspected STS. Patients younger than 18 years, with a prior adverse reaction to iodine or fluorescein, or with renal disease were excluded from the study. Intravenous ICG was infused approximately three hours prior to surgery at a dosage of 2.0-2.5 mg/kg, and following tumor resection, the excised tumor and tumor bed were imaged for fluorescence intensity. When scanning the tumor bed, a threshold of 77% calibrated to the region of maximum intensity in the resected tumor was defined as a positive ICG margin, according to published protocols from the breast cancer literature. ICG results were then compared with the surgeon's clinical impression of margin status and permanent pathology results. Out of 26 subjects recruited for the original study, 18 soft tissue sarcomas (STS) were included for analysis. Three subjects were excluded for having bone sarcomas, and five subjects were excluded due to final pathology, which was ultimately inconsistent with sarcoma. The average age of patients was 64.1 years old (range: 28-83), with an average ICG dose of 201.8 mg. In 56% (10/18) of patients, ICG margins were consistent with the permanent pathology margins, with 89% specificity. The use of ICG as an intraoperative adjunct to obtaining negative margins in soft tissue sarcoma surgery is promising. However, studies with larger sample sizes are warranted to further delineate the accuracy, optimal dosage, timing, and types of sarcoma in which this diagnostic tool may be most useful.

Clinical Application of Indocyanine Green Fluorescence Imaging in the Resection of Hepatoblastoma: A Single Institution's Experiences

Purpose

Indocyanine green (ICG) fluorescence imaging is becoming increasingly popular in adult oncologic surgery, but remains relatively uncommon in pediatric oncologic surgery. Herein, we report our experience with the use of ICG fluorescence imaging in the resection of hepatoblastoma (HB).

Patients and Methods

Hepatoblastoma patients who underwent liver resection with ICG fluorescence imaging between January 2020 and March 2021 were included in this study. Patients’ demographic data, clinical information, and detailed information of the use of ICG fluorescence imaging were retrospectively reviewed.

Results

Sixteen HB patients underwent ICG fluorescence imaging-guided liver resection. There were 11 males and 5 females, age ranged from 8 to 134 months. The initial alpha-fetoprotein ranged from 436 to 528,390 ng/ml. There were one pre-treatment extent of tumor stage I, nine stage II, four stage III, and two stage IV. Three patients underwent up-front hepatectomy, 13 patients received 2–8 cycles of platinum-based neoadjuvant chemotherapy and underwent delayed hepatectomy. ICG (0.5 mg/kg) was given intravenously 48–72 h prior to surgery. The operative time ranged from 180 to 400 min. All patients achieved negative surgical margins. In two patients, ICG identify additional lesions which were not detected in preoperative imaging.

Conclusion

ICG fluorescence imaging is useful in the resection of HB and may detect small lesions not shown in preoperative imaging.

Tumor-Background Ratio is an effective method to identify tumors and false-positive nodules in indocyanine-green navigation surgery for pediatric liver cancer

BACKGROUND

Indocyanine green (ICG) navigation surgery has been used for hepatoblastoma (HB) in children but the technique has been reported for using in other childhood liver cancers were rare. This article summarizes the application experience of ICG in HB and other childhood liver cancers in children and explores the role of fluorescence intensity measurement in identifying tumors.

METHODS

To summarize the clinical experience of children with liver cancer treated by ICG navigation surgery. The tumor and its surrounding tissue were photographed by near infrared during the operation. The fluorescence intensity of tumors, ICG (+) lesions and the normal liver was measured, and the Tumor-Background Ratio (TBR) was calculated.

RESULTS

A total of 11 children with liver cancer were injected intravenously with ICG 1 day before operation. With the help of ICG fluorescence navigation, there was no residual tumor at the surgical margin for all the children. Total fluorescence was seen in 2 cases, rim fluorescence in 2 cases, and partial fluorescence in 7 cases. 19 ICG false-positive nodules were found on the resection stump or residual liver tissue in 5 cases, and the TBR value of tumors was higher than that of false- positive nodules. 10 children have survived without disease.

CONCLUSION

ICG navigation surgery is safe and feasible for liver cancer in children, which can enhance the visualization of the tumor during operation and provide more information about the location and boundaries of the tumor. This technique also has limitations, which can be affected by chemotherapy, tumor location, ICG administration regimen, and equipment. TBR is an effective method to identify tumor and non-cancerous lesions.

Above and Beyond Robotic Surgery and 3D Modelling in Paediatric Cancer Surgery

Although the survival rates for children's cancers have more than doubled in the last few decades, the surgical practise has not significantly changed. Among the most recent innovations introduced in the clinic, robotic surgery and augmented reality are two of the most promising, even if they are not widespread. The increased flexibility of the motion, the magnification of the surgical field and the tremor reduction provided by robotic surgery have been beneficial to perform complex oncological procedures in children. Besides, augmented reality has been proven helpful in planning for tumour removal, facilitating early discrimination between cancer and healthy organs. Nowadays, research in the field of surgical oncology is moving fast, and new technologies and innovations wich will help to shape a new way to perform cancer surgery. Paediatric surgeons need to be ready to adopt these novel devices and intraoperative techniques to allow more radical tumour resections with fewer complications. This review aims to present the mechanism of action and indications of several novel technologies such as optical imaging surgery, high definition cameras, and intraoperative loco-regional treatments. We hope this will enhance early adoption and more research on how to employ technology for the benefit of children.