Background Ganglioneuroblastoma intermixed (GNBi) and ganglioneuroma (GN) are benign subtypes of neuroblastic tumors. Primary observation has become accepted management for some patients with surgical operative strategies evolving to be less aggressive. Objectives Our study examines evolving management in a UK cohort investigating natural history, biology and clinical features of GN and ganglioneuroblastoma-intermixed (GNBi) in those having observation or surgery. Methods Retrospective review of histologically confirmed GN and GNBi managed over a 30 year period. Clinical, pathological features, tumor dimensions, management and outcomes are all recorded. Results A total of 259 patients were identified (GN= 163, GNBi = 93, median age = 62 months). 201(78%) had upfront surgery and 58 (22%) were actively observed. Of the 58 observed - 21 (36%) later required surgery due to progressive tumour growth (52%). Gross total resection was achieved in 79% of patients with a 19% complication rate. Presence of image defined risk factors and large tumour size correlated with incomplete resection (p < 0.05 in both). Forty-five index cases (39%) had change in pathology between biopsy and surgery with 14 patients (12%) altered from ‘favourable‘ to ‘unfavourable’. Conclusion Our findings show surveillance alone may be considered a safe approach. However, a significant number of index patients may eventually require operative surgery with development of symptoms. Extent of surgical resection did not impact overall survival (OS); however it improved symptom(s) resolution.

Background  Indocyanine green (ICG) fluoresces in the near infra-red (NIR) spectrum. It is widely used in adult oncological surgery for identification of tumor margins and lymph node sampling. However, its use in the pediatric population is limited. This is the first study in children to assess its feasibility in minimally invasive surgery (MIS) for oncological disease Methods  This was an open label, prospective, single centre, feasibility study recruiting consecutive patients eligible for MIS tumor resection. ICG was injected intravenously at induction of anaesthesia and/or intra-parenchymally for patients having tumor nephrectomy. Patient demographics, intraoperative appearances, nodal fluorescence, post-operative histopathology, and surgeon Likert ratings were collected. Results Seventeen patients conformed to the inclusion criteria. Five had a Wilms tumor, 4 had lung metastases and 8 had other tumors (neuroblastoma, inflammatory myofibroblastic tumor, ganglioneuroma, phaeochromocytoma, adrenal tumor). For those having lymph node sampling, a median of 8(3-9) nodes were sampled. Lung metastases were easily identifiable, and all had negative margins. Tumors containing viable disease fluoresced and were completely resected, whilst benign and heavily treated tumors were afluorescent. There were no adverse events relating to ICG. Conclusion  Based on this small sample, injection of ICG during induction of anaesthesia is safe and effective in showing tumor margins in patients who have had little or no neoadjuvant chemotherapy as well as in metastectomy in Wilms and osteosarcoma. Its use in renal tumor resection results in adequate nodal sampling. Further studies are needed to confirm these preliminary results.

Lymph node harvest is an integral part of Wilms tumor surgery with both SIOP and COG protocols asking for more than 6 lymph nodes to best evaluate for nodal spread and a subsequent need for intensification of treatment. The majority of studies show that in both open and minimally invasive resections the median number of nodes removed is 4. Indocyanine green and near infrared fluorescence may be the key to solving this problem. In adult gynaecology, colorectal and breast cancers, ICG is used to identify sentinel nodes and facilitate nodal harvest. This report describes its use in Wilms tumor