Comparison of Outcomes Between Surveillance Ultrasound and Completion Lymph Node Dissection in Children and Adolescents With Sentinel Lymph Node-Positive Cutaneous Melanoma.

OBJECTIVE: To determine the impact of nodal basin ultrasound (US) surveillance versus completion lymph node dissection (CLND) in children and adolescents with sentinel lymph node (SLN) positive melanoma. BACKGROUND: Treatment for children and adolescents with melanoma are extrapolated from adult trials. However, there is increasing evidence that important clinical and biological differences exist between pediatric and adult melanoma. METHODS: Patients ≤18 years diagnosed with cutaneous melanoma between 2010 and 2020 from 14 pediatric hospitals were included. Data extracted included demographics, histopathology, nodal basin strategies, surveillance intervals, and survival information. RESULTS: Of 252 patients, 90.1% (n=227) underwent SLN biopsy (SLNB), 50.9% (n=115) had at least 1 positive node. A total of 67 patients underwent CLND with 97.0% (n=65/67) performed after a positive SLNB. In contrast, 46 total patients underwent US observation of nodal basins with 78.3% (n=36/46) of these occurring after positive SLNB. Younger patients were more likely to undergo US surveillance (median age 8.5 y) than CLND (median age 11.3 y; P =0.0103). Overall, 8.9% (n=21/235) experienced disease recurrence: 6 primary, 6 nodal, and 9 distant. There was no difference in recurrence (11.1% vs 18.8%; P =0.28) or death from disease (2.2% vs 9.7%; P =0.36) for those who underwent US versus CLND, respectively. CONCLUSIONS: Children and adolescents with cutaneous melanoma frequently have nodal metastases identified by SLN. Recurrence was more common among patients with thicker primary lesions and positive SLN. No significant differences in oncologic outcomes were observed with US surveillance and CLND following the identification of a positive SLN.

Childhood cancer surgery in low- and middle-income countries.

This report summarizes the status of pediatric surgical oncology services in low- and middle-income countries. Factors such as surgical capacity and enablers, and barriers to providing pediatric surgical oncology services are discussed. A review of the literature was conducted to examine the evidence for the capacity of low- and middle-income countries to provide childhood cancer surgery services, focusing on general surgery. Unpublished, ongoing work and initiatives of international organizations are also described.

Imaging adjuvants in pediatric surgical oncology.

Surgery is a crucial component of pediatric cancer treatment, but conventional methods may lack precision. Image-guided surgery, including fluorescent and radioguided techniques, offers promise for enhancing tumor localization and facilitating precise resection. Intraoperative molecular imaging utilizes agents like indocyanine green to direct surgeons to occult deposits of tumor and to delineate tumor margins. Next-generation agents target tumors directly to improve specificity. Radioguided surgery, employing tracers like metaiodobenzylguanidine (MIBG), complements fluorescent techniques by allowing for detection of tumors at a greater depth. Dual-labeled agents combining both modalities are under development. Three-dimensional modeling and virtual/augmented reality aid in preoperative planning and intraoperative guidance. The above techniques show great promise to benefit patients with pediatric tumors, and their continued development will almost certainly improve surgical outcomes.

Documentation of critical intraoperative oncologic findings: Synoptic versus narrative operative reports for childhood cancer surgery.

BACKGROUND: Documentation of intraoperative oncologic findings varies greatly across narrative operative reports (NRs). An international panel of childhood cancer experts recently developed a synoptic operative report (SR) for childhood cancer surgeries. The aim of this study was to compare the documentation of critical intraoperative findings in NRs versus SRs. METHODS: A single-center retrospective review of all surgical resections of primary solid tumors at our pediatric oncology center was conducted from June 2023 to March 2024, after an institutional SR was piloted from October 2023 onwards. Data collected included the presence or absence of six components included in standard pediatric oncology NRs. Inclusion rates were calculated as percentages for each component. Due to the small sample, the Fisher's exact test was used for all hypothesis testing. RESULTS: Seventy primary tumor resections were performed during the study period, as documented by 38 NRs and 32 SRs. All operative reports after October 2023 were SRs. Completeness of tumor resection and specimen naming were consistently documented in NRs (86% and 100%, respectively) and SRs (100% and 100%, respectively). The presence/absence of three components-intraoperative tumor spillage (31%), vascular involvement (31%), and lymph node sampling (26%)-were documented in fewer than a third of the NRs. Documentation of the presence/absence of locoregional spread, intraoperative tumor spillage, vascular involvement, and lymph node sampling was significantly better in SRs than in NRs. CONCLUSION: Adoption of SRs significantly improved the documentation of critical intraoperative findings. Thus, we recommend using SRs in pediatric solid tumor surgery.

Image-guided core-needle or surgical biopsy for neuroblastoma diagnosis in children: A systematic review and meta-analysis from the International Society of Pediatric Surgical Oncology (IPSO).

BACKGROUND: Image-guided core-needle biopsy (IGCNB) is a widely used and valuable clinical tool for tissue diagnosis of pediatric neuroblastoma. However, open surgical biopsy remains common practice even if children undergo more invasive and painful procedures. This review aims to determine the diagnostic accuracy and safety of IGCNBs in pediatric patients with neuroblastoma. METHODS: We conducted a systematic review of peer-reviewed original articles published between 1980 and 2023, by searching "pediatric oncology," "biopsy," "interventional radiology," and "neuroblastoma." Exclusion criteria were patients older than 18 years, studies concerning non-neurogenic tumors, case reports, and language other than English. Both the systematic review and meta-analysis were conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. RESULTS: A total of 533 abstracts articles were analyzed. Of these, eight retrospective studies met inclusion criteria (490 infants, 270 surgical biopsies [SB], 220 image-guided biopsies). Tissue adequacy for primary diagnosis (SB: n = 265, 98%; IGCNB: n = 199, 90%; p = .1) and biological characterization (SB: n = 186, 95%; IGCNB: n = 109, 89%; p = .15) was similar with both biopsy techniques, while intraoperative transfusion rate (SB: n = 51, 22%; IGCNB: n = 12, 6%; p = .0002) and complications (%) (SB: n = 58, 21%; IGCNB: n = 14, 6%; p = .005) were higher with surgical biopsy. Length of stay was similar in both groups; however, no additional data about concurrent diagnostic or treatment procedures were available in the analyzed studies. CONCLUSIONS: IGCNB is a safe and effective strategic approach for diagnostic workup of NB and should be considered in preferance to SB wherever possible.

Management of Chyle Leak in Pediatric Surgical Oncology: A Systematic Review.

INTRODUCTION: Chyle leak, a rare complication, arises from damage to primary lymphatic vessels due to congenital factors or medical interventions, leading to conditions such as chylothorax and chylous ascites. Managing chyle leaks is challenging, especially in pediatric surgical oncology, often arising as postoperative complications. Treatment options range from conservative dietary adjustments to surgical interventions, depending on leak severity and patient condition. This systematic review examines the management of chyle leaks in pediatric surgical oncology, emphasizing both conservative and surgical approaches. METHODS: This systematic review involved extensive database searches (EMBASE, Web of Science, and PubMed) to identify relevant studies on chyle leak management in the pediatric population. The review included studies from 1982 to 2023 and focused on pediatric and adolescent patients, assessing various treatment approaches and outcomes. Nine articles composed of 163 patients (study population size ranging from 2 to 82 patients). Independent reviewers evaluated the selected studies for inclusion. RESULTS: Among 9 articles analyzed, 98.8% of pediatric patients initially received conservative management for chyle leaks, with 11.7% eventually requiring surgical intervention due to persistent leaks (8, 10, and 16 to 22). Neuroblastoma resection is associated with 20% to 40% rate of chyle leak, and the extent of lymphadenectomy has been identified as a risk factor for chyle leak. The study highlighted variability in clinical success rates based on conservative management approaches. DISCUSSION: Chyle leak, while rare, presents a complex challenge, especially in pediatric surgical oncology. Various causes and treatment options exist, with a preference for conservative management initially and surgical intervention in specific circumstances. Factors such as leak severity and patient condition guide the choice between approaches. However, the scarcity of comparative data and randomized trials in the pediatric population necessitates further research to establish optimal management strategies for chyle leaks. CONCLUSIONS: Conservative management of chyle leaks has proven to be the preferred approach in early stages of treatment, whereas surgical management could be the preferred choice in certain situations. Larger prospective studies are needed to further evaluate these results.

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.

Evidence-based surgical guidelines for treating children with Wilms tumor in low-resource settings.

BACKGROUND: Survival of Wilms tumor (WT) is > 90% in high-resource settings but < 30% in low-resource settings. Adapting a standardized surgical approach to WT is challenging in low-resource settings, but a local control strategy is crucial to improving outcomes. OBJECTIVE: Provide resource-sensitive recommendations for the surgical management of WT. METHODS: We performed a systematic review of PubMed and EMBASE through July 7, 2020, and used the GRADE approach to assess evidence and recommendations. RECOMMENDATIONS: Initiation of treatment should be expedited, and surgery should be done in a high-volume setting. Cross-sectional imaging should be done to optimize preoperative planning. For patients with typical clinical features of WT, biopsy should not be done before chemotherapy, and neoadjuvant chemotherapy should precede surgical resection. Also, resection should include a large transperitoneal laparotomy, adequate lymph node sampling, and documentation of staging findings. For WT with tumor thrombus in the inferior vena cava, neoadjuvant chemotherapy should be given before en bloc resection of the tumor and thrombus and evaluation for viable tumor thrombus. For those with bilateral WT, neoadjuvant chemotherapy should be given for 6-12 weeks. Neither routine use of complex hilar control techniques during nephron-sparing surgery nor nephron-sparing resection for unilateral WT with a normal contralateral kidney is recommended. When indicated, postoperative radiotherapy should be administered within 14 days of surgery. Post-chemotherapy pulmonary oligometastasis should be resected when feasible, if local protocols allow omission of whole-lung irradiation in patients with nonanaplastic histology stage IV WT with pulmonary metastasis without evidence of extrapulmonary metastasis. CONCLUSION: We provide evidence-based recommendations for the surgical management of WT, considering the benefits/risks associated with limited-resource settings.

A CT scan-based formula for predicting central venous catheter length in pediatric patients.

PURPOSE: Placement of a central venous catheter (CVC) is the most commonly performed pediatric procedure. This study aims to develop simple formulas to calculate intravascular length of CVCs prior to insertion to minimize reliance on fluoroscopic and radiographic imaging, which may not be uniformly available. METHODS: We performed a single-institution, retrospective review of 115 pediatric patients who received both CVC placement and computed tomography (CT) imaging of the chest within 3 months of the procedure. Using measurements from the CT imaging, formulas calculating the length of the intravascular component of the CVC based on height and insertion laterality were developed and compared to previously published formulas. These formulas were then trialed prospectively to validate reliability and application. RESULTS: Formulas were developed for right-sided and left subclavian insertion. The right-side formula accurately predicted CVC length in 52.6% of patients, compared to 47.4% by the Andropoulos formula. The left subclavian formula accurately estimated 62.5%, compared to 34.5% by the Stroud formula. CONCLUSIONS: The optimal intravascular length of central venous catheters may be determined by simple formulas based on patient height and insertion site. LEVEL OF EVIDENCE: III.

Female Fertility Cryopreservation Outcomes in Childhood Cancer: A Systematic Review.

BACKGROUND AND AIMS: As survival rates in childhood cancer progress significantly, health outcomes in adulthood are pivotal to quality of life (QoL). Female patients undergoing chemotherapy and radiation for childhood cancer may experience adverse effects such as gonadotoxicity-related ovarian insufficiency. Ovarian tissue cryopreservation (OTC) is well studied in adults, but has only recently started to be explored in an effort to preserve fertility in young patients with childhood cancer. This systematic review aims to critically highlight contemporary outcomes of cryopreservation in female pediatric cancer patients. METHODS: A systematic search was conducted in PubMed, Embase, and Web of Science databases to identify English-language full text articles and abstracts published between 2004 and 2022 describing cryopreservation among female children (0-21 years old) with cancer. Abstracts and full-text articles were screened for inclusion. Subsequently, data from eligible studies was extracted and analyzed. Descriptive statistics were utilized to estimate overall outcomes of cryopreservation. RESULTS: Of 104 abstracts and 34 full-text articles, 12 studies were included. Data was collected from 7 world countries and involved some 612 pediatric and adolescent patients with malignant disease. Most common cancers included hematological malignant disease (81%), CNS nervous system malignant tumors (56%), and sarcomas (39%). Of the 6 studies with full reporting, OTC was undertaken in 501 patients, and 5.9% (30/501) of these patients underwent ovarian tissue transplantation (OTT). After OTT, 27 patients desired pregnancy and 33% (9/27) became pregnant. Six of these 9 patients (67%) had live births. CONCLUSIONS: Preliminary analysis showed that OTC has been successfully performed but not yet studied thoroughly in pediatric cancer patients in a longitudinal manner. This study has further shown that cryopreservation outcomes are mainly reported among adult patients living in high income countries, demonstrating a crucial need for long-term outcome studies focused on pediatric and prepuberal OTC, subsequent OTT, and potential pregnancy. This work is considered critical to aid standardize recommendations of fertility preservation in childhood cancer patients and to better inform the efficacy of these procedures to benefit patients in world nations of all fiscal income levels. LEVEL OF EVIDENCE: Level III.

Use of Vacuum-Assisted Closure to Reduce the Likelihood of Wound Complications After Limb-Sparing Resection of Pediatric Primary Bone Sarcomas of the Femur.

BACKGROUND: Limb-sparing surgery is the standard of care for primary bone tumors. However, such procedures are associated with high rates of wound complications, specifically in lower-extremity surgeries. Therefore, identifying and implementing interventions to minimize the likelihood of wound complications after limb-sparing resection of the lower extremity is crucial. METHODS: Patients who underwent limb-sparing osteosarcoma or Ewing sarcoma resection during a 7-year period at a single institution were retrospectively reviewed. Data were collected on 39 patients who underwent limb-sparing resection of the femur. Patient demographics, tumor characteristics, and perioperative and postoperative data were extracted and analyzed. Patients who underwent resection before April 2017 received conventional postoperative incision dressings. Starting in April 2017, patients received vacuum-assisted closure (VAC) with the 3 M™ Prevena VAC system after surgical closure. Eighteen patients received conventional postoperative incision dressing, and 21 received incisional wound VAC. A wound complication was defined as any Clavien-Dindo classification greater than 0 within a 28-day postoperative period. RESULTS: Patients who received postoperative incisional wound VAC had lower rates of wound complications than those who received conventional incision dressings (14% vs. 50%; p = 0.035). Additionally, patients in whom wound complications developed had a longer average hospital stay than those without wound complications (5 days vs. 4 days; p = 0.029). CONCLUSIONS: Wound complications prolong the hospital stay and can delay adjuvant chemotherapy for bone tumors. The use of postoperative incisional wound VAC is associated with less likelihood of wound complications and should be considered in any high-risk surgical closure. LEVEL OF EVIDENCE: Level III Treatment Study.

A research definition and framework for acute paediatric critical illness across resource-variable settings: a modified Delphi consensus.

The true global burden of paediatric critical illness remains unknown. Studies on children with life-threatening conditions are hindered by the absence of a common definition for acute paediatric critical illness (DEFCRIT) that outlines components and attributes of critical illness and does not depend on local capacity to provide critical care. We present an evidence-informed consensus definition and framework for acute paediatric critical illness. DEFCRIT was developed following a scoping review of 29 studies and key concepts identified by an interdisciplinary, international core expert panel (n=24). A modified Delphi process was then done with a panel of multidisciplinary health-care global experts (n=109) until consensus was reached on eight essential attributes and 28 statements as the basis of DEFCRIT. Consensus was reached in two Delphi rounds with an expert retention rate of 89%. The final consensus definition for acute paediatric critical illness is: an infant, child, or adolescent with an illness, injury, or post-operative state that increases the risk for or results in acute physiological instability (abnormal physiological parameters or vital organ dysfunction or failure) or a clinical support requirement (such as frequent or continuous monitoring or time-sensitive interventions) to prevent further deterioration or death. The proposed definition and framework provide the conceptual clarity needed for a unified approach for global research across resource-variable settings. Future work will centre on validating DEFCRIT and determining high priority measures and guidelines for data collection and analysis that will promote its use in research.

Indocyanine green fluorescence-guided lymphadenectomy with single site retroperitoneoscopy in children.

BACKGROUND: Retroperitoneoscopic lymphadenectomy is an established surgical approach in adult urology, but rarely described in pediatric population. METHODS: We develop retroperitoneoscopic surgical oncology in children, combining new technology innovations in pediatric surgery such as single site port retroperitoneoscopic in supine position and indocyanine green (ICG). RESULTS: The video describes a step-by-step approach from the ICG injection technique to the lymph-node retroperitoneoscopic harvesting. The video highlights anatomical landmarks and ICG intraoperative lymph nodes findings. Four consecutive surgical procedures were performed in children with paratesticular rhabdomyosarcoma who required staging template retroperitoneal lymph node dissection (RPLND) for staging. All patients were discharged the same day without 30-days postoperative complications. CONCLUSION: Retroperitoneoscopic approach with single port and indocyanine guided lymphatic mapping for template retroperitoneal lymph node dissection (RPLND) is a feasible minimally invasive procedure in children. Combining different technology innovations allows an effective lymph node harvesting with the possibility to offer an enhanced recovery after surgery in pediatric oncology population.

Retroperitoneoscopic or Transperitoneal Approach for Neurogenic and Adrenal Tumors in Children? A Comparison on the Way to Enhanced Recovery in Pediatric Surgical Oncology.

BACKGROUND: Minimally invasive surgery is increasingly utilized for resection of neurogenic tumors in children. The minimally invasive retroperitoneoscopic approach was recently reported in children, but transperitoneal laparoscopy still remains the most common technique. The aim of this study is to compare a novel single-port retroperitoneoscopy (SPR) approach for pediatric neurogenic tumor resection with transperitoneal laparoscopic (TPL). METHODS: Patients undergoing minimally invasive resection of abdominal neurogenic tumors over 5 years at a single institution (from 2018 to 2022) were retrospectively reviewed. Tumor volume, stage, presence of image-defined risk factors (IDRFs), neoadjuvant chemotherapy, operative time, estimated blood loss (EBL), length of stay (LOS), complications, oral morphine equivalents per kilogram (OME/Kg), and time to chemotherapy were assessed and compared with SPR and TPL approaches. RESULTS: Eighteen and fifteen patients underwent TPL and SPR, respectively. No significant differences were found between the TPL and SPR approaches in terms of tumor characteristics and IDRFs. Patients who underwent SPR had a significantly faster recovery (p = 0.008) and less postoperative opioid use compared to those in TPL (p = 0.02), thus allowing an enhanced recovery after surgery (ERAS) protocol application. TPL and SPR approaches were performed in presence of IDRFs, respectively in 2 (11%) and 4 patients (27%), with a IDRFs-related conversion in one TPL procedure. Both approaches had one < Grade 3 Clavien Dindo complication, but not requiring further surgery. DISCUSSION: SPR approach can be considered as a safe and feasible minimally invasive approach for the resection of pediatric primary adrenal and neurogenic tumors. The retroperitoneoscopic approach performed using a single port technique represents a promising new frontier of ERAS application in pediatric surgical oncology. CONCLUSION: SPR is a viable surgical alternative in selected neurogenic abdominal tumors with limited IDRFs, thus allowing for the application of ERAS protocols in these patients. LEVEL OF EVIDENCE: Level III.

Malignant Peripheral Nerve Sheath Tumors-A Comprehensive Review of Pathophysiology, Diagnosis, and Multidisciplinary Management.

Malignant peripheral nerve sheath tumors (MPNSTs) are aggressive soft tissue sarcomas (STS) with nerve sheath differentiation and a tendency to metastasize. Although occurring at an incidence of 0.001% in the general population, they are relatively common in individuals with neurofibromatosis type 1 (NF1), for whom the lifetime risk approaches 10%. The staging of MPNSTs is complicated and requires close multi-disciplinary collaboration. Their primary management is most often surgical in nature, with non-surgical modalities playing a supportive, necessary role, particularly in metastatic, invasive, or widespread disease. We, therefore, sought to provide a comprehensive review of the relevant literature describing the characteristics of these tumors, their pathophysiology and risk factors, their diagnosis, and their multi-disciplinary treatment. A close partnership between surgical and medical oncologists is therefore necessary. Advances in the molecular characterization of these tumors have also begun to allow the integration of targeted RAS/RAF/MEK/ERK pathway inhibitors into MPNST management.

Fluorescence-guided lymph node sampling is feasible during up-front or delayed nephrectomy for Wilms tumor.

BACKGROUND: Lymph node sampling is critical to surgical staging in Wilms tumor; failure to sample lymph nodes is associated with under-staging and an increased incidence of local relapse. However, no standard lymphatic mapping method is currently being utilized for Wilms tumor to aid identification of regional draining lymph nodes. Herein, we describe the use of fluorescence-guided lymphatic mapping for Wilms tumor. MATERIALS AND METHODS: Two tertiary level referral centers independently began indocyanine green (ICG) fluorescence-guided nodal mapping. In one center, this was achieved with ipsilateral intra-parenchymal (IP) injection of ICG during minimally invasive tumor nephrectomy (MIN) following neoadjuvant chemotherapy and in the other, with Peri­Hilar (PH) injection during upfront, open tumor nephrectomy (ON). Successful lymph node mapping was defined as the presence of fluorescence signal in draining lymph nodes. RESULTS: Eight patients (median age of 2.5 years) underwent fluorescence-guided lymphatic mapping (four IP and four PH injection). Lymphatic mapping was successful in seven patients (88%) including each of the four patients with IP injection. CONCLUSIONS: Fluorescence-guided lymphatic mapping of Wilms tumor drainage is feasible by both IP injection and PH injection techniques. However, whether lymphatic mapping improves the precision of lymph node sampling is unknown and should be studied in prospective trials.

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

BACKGROUND: Indocyanine green (ICG), a water-soluble tricarbocyanine fluorophore, is being increasingly used for tumor localization based on its passive intra-tumoral accumulation due to enhanced permeability and retention in tumor tissue. Therefore, we hypothesized that ICG can provide contrast to facilitate accurate, real-time recognition of renal tumors at the time of nephron-sparing surgery in children. METHODS: This retrospective study examined the feasibility of ICG in guiding nephron-sparing surgery for pediatric renal tumors. RESULTS: We reviewed the medical records of 8 pediatric patients with renal tumors in 12 kidneys. Intraoperative localization of tumor with near infrared guidance was successful in all 12 kidneys. However, we consistently found an inverse pattern of near infrared signal in which the normal kidney demonstrated increased fluorescent signal relative to the kidney tumor. CONCLUSIONS: Fluorescence-guided renal tumor delineation is unique because it has an inverse pattern of near infrared signal in which the normal kidney demonstrates increased signal relative to the adjacent tumor. Nevertheless fluorescence-guided distinguishing of renal tumor from surrounding normal kidney is feasible.