Dasgupta, Roshni

Background: Real-time intraoperative discrimination of malignant tissue during pediatric solid tumor resection is limited, constraining margin optimization; the utility of indocyanine green (ICG) fluorescence in this population remains incompletely defined. Study Design: Prospective, observational, multi-institutional study (2019–2023) of pediatric, adolescent, and young adult patients undergoing resection of intra-abdominal solid malignancies following preoperative ICG administration. The primary endpoint was diagnostic accuracy of ICG fluorescence for tumor-containing specimens; secondary endpoints included association with margin status and surgeon-perceived intraoperative benefit. Results: Forty-three operations in 42 patients yielded 55 specimens, of which 47 (85%) were malignant. Diagnostic performance was highest in hepatic tumors (sensitivity 83%, positive predictive value 83%) and lower in adrenal and heterogeneous tumor types. ICG avidity was not associated with improved negative margin rates (86% vs 75%, p=0.47). Surgeons reported intraoperative benefit in 67% of cases, most commonly improved visualization. No ICG-related adverse events occurred. Conclusions: ICG fluorescence provides reliable tumor identification in hepatic malignancies but does not correlate with margin-negative resection, indicating limited utility for margin guidance. These data support tumor-specific application and further investigation of optimized fluorescence strategies, including dosing, timing, and alternative fluorophores, in pediatric oncologic surgery.

ABSTRACT Purpose Malignant rhabdoid tumor of the kidney (MRTK) is a rare, aggressive tumor seen in young children. The optimal timing of resection for locally advanced tumors is not well‐defined. The purpose of this study is to evaluate modern oncologic outcomes and the impact of surgical timing. Methods A multicenter retrospective review was performed by institutions participating in the Pediatric Surgical Oncology Research Collaborative. Children younger than 21 years old with MRTK diagnosed between 2000 and 2022 were included. Results Sixty‐nine patients were identified with MRTK and met the inclusion criteria. Median age of diagnosis was 10.1 months. Overall survival (OS) at 1, 5, and 10 years was 49%, 32%, and 19%, respectively. Patients with local Stage III disease who underwent upfront resection ( n = 18) compared to those who had delayed resection after NAT ( n = 15) had a similar OS, median OS greater than 60 months versus 14.6 months, respectively; p = 0.396. The surgical timing groups were balanced in terms of the presence of metastasis, length of follow‐up, and tumor characteristics. There was one occurrence of primary intraoperative tumor spill and two occurrences of organ injury in the upfront resection group compared to none in the delayed resection group. Conclusion MRTK carries a poor prognosis despite multimodal treatment. Histologic diagnosis may not be confirmed at presentation, and MRTK cannot be reliably distinguished from Wilms tumor on imaging alone. As overall survival is similar, the decision regarding surgical timing in locally advanced tumors should be individualized based on perceived resectability, balancing the risk of intraoperative complications against the possibility of tumor progression during neoadjuvant therapy.

ABSTRACT Background Sentinel lymph node (SLN) biopsy is a critical staging tool in skin and soft tissue cancers. Although technetium lymphoscintigraphy is the most common adjunct, indocyanine green (ICG) demonstrates a promising alternative in pediatric, adolescent, and young adult (AYA) skin and soft tissue cancers. Methods and Objectives Evaluate the safety and efficacy of ICG in SLN biopsy (SLNB) in diverse pediatric and AYA solid cancers in a multi‐institutional environment. This is a prospective, observational study conducted at 13 member institutions in the Pediatric Surgical Oncology Research Collaborative between 2019 and 2023. Eligible patients underwent SLNB for primary or recurrent solid skin and soft tissue tumors. Peritumoral ICG was administered intraoperatively. Outcomes included SLN detection rates, histopathology of excised specimens, and surgeon‐reported assessment of utility. Safety was assessed through adverse event reporting. Results Forty SLNB procedures yielded 84 specimens: 13 melanoma (32.5%), 12 squamous cell carcinoma (30%), 11 non‐rhabdomyosarcoma soft tissue sarcoma (27.5%), two rhabdomyosarcoma (5%), one Ewing sarcoma (2.5%), and one malignant peripheral nerve sheath tumor (2.5%). Histologic evaluation identified 81 lymph nodes, 75 benign (89.3%) and six malignant (7.1%); three specimens were adipose tissue (3.6%). Of 81 lymph nodes, 76% were ICG‐positive. ICG had a sensitivity of 79.5%, a specificity of 33%, and a positive predictive value of 96%. All malignant nodes were ICG‐avid. There were no adverse reactions to ICG at 30 days. Conclusions ICG is a safe and effective adjunct for SLNB in pediatric and AYA soft tissue and skin malignancies.

ABSTRACTAccurate staging of nodal involvement in pediatric sarcoma patients is important to determine correct systemic and local therapy, with the goal to reduce subsequent recurrences. However, differences in lymph node staging strategies, definitions, and treatment protocols between the Children's Oncology Group (COG), European paediatric Soft tissue sarcoma Study Group (EpSSG), and the Cooperative Weichteilsarkom Studiengruppe (CWS) complicate comparisons. In this article, we aim to establish internationally recognized recommendations for lymph node assessment and treatment of children and adolescents diagnosed with rhabdomyosarcoma (RMS) and non‐rhabdomyosarcoma soft tissue sarcoma (NRSTS) according to the Consensus Conference Standard Operating Procedure methodology.

Trends in diagnostic biopsy sample collection approaches for primary bone sarcomas have shifted in the past 2 decades. Although open/incisional biopsies used to be the predominant approach to obtain diagnostic material for Ewing sarcoma and osteosarcoma, image-guided core needle biopsies have increased in frequency and are safe for patients. These procedures are less invasive and reduce recovery times but have potential limitations. The quantity and quality of tissue obtained through these procedures vary between institutions. Acquired viable tissue volumes can be low, limiting the conduct of downstream expanded clinical workup, molecular analyses, and research. Patients with advanced Ewing sarcoma and osteosarcoma continue to have overall poor outcomes despite dose-intensive cytotoxic chemotherapy. The biology of treatment resistance is not currently well understood, partly due to limited availability of relevant tissue to study. There is a need for access to quality tumor specimens for molecular and other analyses to identify high-risk tumor subsets and drive discovery to improve patient outcomes. Given broad variability in bone tumor tissue procurement and processing across member institutions, the Children’s Oncology Group Bone Tumor Committee convened a multidisciplinary group of experts to outline the current and near-future tissue needs for optimal clinical care and access to research platforms. The goal of this working group was to provide high-level guidance on biopsy practices that safely meet these evolving needs. Harmonizing tissue collection practices is paramount to improving the care of children, adolescents, and young adults diagnosed with Ewing sarcoma and osteosarcoma.