Upward Lightning at Wind Turbines: Risk Assessment From Larger-Scale Meteorology.

Upward lightning (UL) has become a major threat to the growing number of wind turbines producing renewable electricity. It can be much more destructive than downward lightning due to the large charge transfer involved in the discharge process. Ground-truth lightning current measurements indicate that less than 50% of UL could be detected by lightning location systems (LLS). UL is expected to be the dominant lightning type during the cold season. However, current standards for assessing the risk of lightning at wind turbines mainly consider summer lightning, which is derived from LLS. This study assesses the risk of LLS-detectable and LLS-undetectable UL at wind turbines using direct UL measurements at instrumented towers. These are linked to meteorological data using random forests. The meteorological drivers for the absence/occurrence of UL are found from these models. In a second step, the results of the tower-trained models are extended to a larger study area (central and northern Germany). The tower-trained models for LLS-detectable lightning are independently verified at wind turbine sites in this area and found to reliably diagnose this type of UL. Risk maps based on cold season case study events show that high probabilities in the study area coincide with actual UL flashes. This lends credibility to the application of the model to all UL types, increasing both risk and affected areas.

[Hospital-based Home Care for Children with Cancer from the Parents̓ Point of View - A Qualitative Exploration of Family Members]. / Die ambulant-aufsuchende Versorgung von an Krebs erkrankten Kindern aus Sicht der Erziehungsberechtigten.

BACKGROUND: About 2,200 children and adolescents in Germany per year are diagnosed with oncological diseases. Through now, there are almost no offers for home care services for these patients. There is a pilot program offering hospital-based home care for children and adolescents with cancer in Germany. The perspective of the parents will be researched by a qualitative exploring study. PATIENTS: In this interview study parents from children with cancer will be interviewed. METHOD: A qualitative exploring interview study, seeking the subjective perspective from parents on the hospital-based home care for children with cancer. The sample was drawn criterion-guided. The interviews were transcribed verbatim and analysed using qualitative content analysis. For socio- demographic characteristics the participants respond to an online questionnaire. RESULTS: Eleven women and three men aged between 30 and 60 years participated in the interviews. The average age of the ill children was 8.43 years. Five parents state that the children's illness did not lead to a reduction in working hours or to the termination of the employment relationship. Hospital-based home care results in subjectively perceived relief in everyday family life, especially in terms of time. Furthermore, a reduction in the psychological perception of stress is described. DISCUSSION/CONCLUSION: Due to the study design, the results presented here are to be regarded as indicative. In future studies the presented results should be supplemented by quantitative representative studies.

Multimodal Therapy with Consolidating Haploidentical Stem Cell Transplantation and Dinutuximab Beta for Patients with High-Risk Neuroblastoma and Central Nervous System Relapse.

Despite highly intensive multimodality treatment regimens, the prognosis of patients with high-risk neuroblastoma (HRNB) and central nervous system (CNS) relapse remains poor. We retrospectively reviewed data from 13 patients with HRNB and CNS relapse who received multimodal therapy with consolidating haploidentical stem cell transplantation (haplo-SCT) followed by dinutuximab beta ± subcutaneous interleukin-2 (scIL-2). Following individual relapse treatment, patients aged 1-21 years underwent haplo-SCT with T/B-cell-depleted grafts followed by dinutuximab beta 20 mg/m2/day × 5 days for 5-6 cycles. If a response was demonstrated after cycle 5 or 6, patients received up to nine treatment cycles. After haplo-SCT, eight patients had a complete response, four had a partial response, and one had a stable disease. All 13 patients received ≥3 cycles of immunotherapy. At the end of the follow-up, 9/13 patients (66.7%) demonstrated complete response. As of July 2023, all nine patients remain disease-free, with a median follow-up time of 5.1 years since relapse. Estimated 5-year event-free and overall survival rates were 55.5% and 65.27%, respectively. Dinutuximab beta ± scIL-2 following haplo-SCT is a promising treatment option with a generally well-tolerated safety profile for patients with HRNB and CNS relapse.

Amplification of annual and diurnal cycles of alpine lightning.

The response of lightning to a changing climate is not fully understood. Historic trends of proxies known for fostering convective environments suggest an increase of lightning over large parts of Europe. Since lightning results from the interaction of processes on many scales, as many of these processes as possible must be considered for a comprehensive answer. Recent achievements of decade-long seamless lightning measurements and hourly reanalyses of atmospheric conditions including cloud micro-physics combined with flexible regression techniques have made a reliable reconstruction of cloud-to-ground lightning down to its seasonally varying diurnal cycle feasible. The European Eastern Alps and their surroundings are chosen as reconstruction region since this domain includes a large variety of land-cover, topographical and atmospheric circulation conditions. The most intense changes over the four decades from 1980 to 2019 occurred over the high Alps where lightning activity doubled in the 2010 s compared to the 1980 s. There, the lightning season reaches a higher maximum and starts one month earlier. Diurnally, the peak is up to 50% stronger with more lightning strikes in the afternoon and evening hours. Signals along the southern and northern alpine rim are similar but weaker whereas the flatlands surrounding the Alps have no significant trend.

Image-defined risk factors in localized thoracic neuroblastoma and ganglioneuroma.

BACKGROUND: The pretreatment International Neuroblastoma Risk Group Staging System (INRGSS) discriminates localized tumors L1/L2 depending on the absence/presence of image-defined risk factors (IDRFs) at diagnosis. Referring to this new staging system, we assessed initial imaging of localized thoracic neuroblastoma (NB) and ganglioneuroma (GN) and the extent of initial tumor resection. METHODS: Patients with localized thoracic NB/GN from the German clinical trials NB97 and NB2004 were included. Imaging at diagnosis and operative reports were reviewed retrospectively. IDRFs were assessed centrally and correlated to International Neuroblastoma Staging System (INSS) stage and extent of tumor resection. Additionally, we analyzed data on surgery-related complications. RESULTS: Imaging series of 88 patients were available for central review. In 18 children, no IDRF was present, 28 exhibited one IDRF, 42 two or more IDRFs, resulting in 70 patients with L2 disease. The most frequently observed IDRF was encasement of any vessel (n = 38). Initial surgical resection was aimed for in 45 patients (L1: n = 11; L2: n = 34). Complete and gross total resection rates were higher children with L2 NB (n = 8/25 L1, n = 17/25 L2 vs. n = 2/15 L1, n = 13/15 L2, respectively). The proportion of surgical complications was very similar between INRGSS L1 and L2 (n = 4/11 vs. n = 17/34). All complications were manageable, and no surgery-related deaths were observed. CONCLUSION: In this retrospective cohort, the extent of resection and the rate of surgical complications did not differ substantially between patients classified as L1/L2, indicating that INRGSS L2 does not equate unresectability. It appeared that individual IDRFs differ in value. Larger studies are needed to assess the significance and therapeutic/prognostic impact of such findings.

The Diagnosis and Treatment of Osteosarcoma and Ewing's Sarcoma in Children and Adolescents.

BACKGROUND: Osteosarcoma and Ewing's sarcoma in children and adolescents require age-specific interdisciplinary diagnosis and treatment to achieve optimal therapeutic outcomes. METHODS: The diagnosis and treatment of malignant bone tumors in childhood and adolescence are presented in the light of publications retrieved by a selective search, pertinent guidelines, and the authors' extensive experience in an interdisciplinary cancer center. RESULTS: Bone sarcomas make up approximately 5% of all malignancies in children and adolescents; the most common types are Ewing's sarcoma and osteosarcoma. Patients are often not referred to a specialized center until long after the onset of symptoms, as they and their physicians rarely consider the possibility of a bone tumor, and the symptoms are often trivialized. Bone pain of unknown origin, swelling, and functional limitations should be investigated with conventional x-rays. Lesions of unclear origin should be biopsied after a meticulous clinical and radiologic evaluation. Multimodal treatment consists of neo - adjuvant chemotherapy, limb-preserving resection if possible, and radiotherapy where indicated. In multicenter studies, patients with osteosarcoma achieve event-free survival in 64% of cases if their disease is localized, and 28% if it is metastatic; the corresponding figures for patients with Ewing's sarcoma are 80% and 27%, respectively. CONCLUSION: With implementation of the current treatment recommendations, most children and adolescents with malignant bone tumors can be treated successfully with curative intent. These patients should be referred to a sarcoma center for diagnosis and treatment.

Differentiated Thyroid Cancer in Adolescents: Single Center Experience and Considerations for Surgical Management and Radioiodine Treatment

Objective: Differentiated thyroid cancer (DTC) in adolescents rare but with a favorable outcome, despite higher rates of cervical lymph node and pulmonary metastasis compared to adults. The aim of this study was to critically evaluate treatment of adolescents with DTC at a single center. Methods: Patients receiving postoperative radioiodine treatment (RAIT) for DTC between 2005 and 2020 at our institution were screened to identify adolescents according to the World Health Organization definition (10-19 years of age). Demographics, clinico-pathological characteristics, treatment and outcome were analyzed. Results: Among 1,897 DTC patients, 23 (1.3%) were adolescents with a median (range) age of 16 (10-18) years. The female to male ratio was 3.6:1. Sixty percent had classic papillary thyroid cancer, with follicular variant in 40%, which was higher than previously reported (15-25%) for this age group. pT-status was pT1 in 9 (39.2%), pT2 in 8 (34.8%), pT3 in 3 (13%) and pT4 in 3 (13%) patients. In 19 (82.6%) patients, central lymphadenectomy was performed and metastasis was seen in 57%. All patients received RAIT with initial activities of 1.2 (n=1, 4.3%), 2 (n=12, 52.2%) or 3.7 GBq (n=10, 43.5%). Eighteen (78.2%) patients were free of biochemical and radiologic disease at a median follow-up of 60.7 months. Second-line surgery for lymph node relapse was necessary in 3 (13%) cases. There was one disease-associated death. Conclusion: Despite high rates of metastasis, most patients were cured, and second-line surgery was rarely required. Further prospective studies are needed to determine whether less aggressive surgical management or omitting adjuvant RAIT are feasible in patients with limited stages at diagnosis.

Independent Validation of a Deep Learning nnU-Net Tool for Neuroblastoma Detection and Segmentation in MR Images.

OBJECTIVES: To externally validate and assess the accuracy of a previously trained fully automatic nnU-Net CNN algorithm to identify and segment primary neuroblastoma tumors in MR images in a large children cohort. METHODS: An international multicenter, multivendor imaging repository of patients with neuroblastic tumors was used to validate the performance of a trained Machine Learning (ML) tool to identify and delineate primary neuroblastoma tumors. The dataset was heterogeneous and completely independent from the one used to train and tune the model, consisting of 300 children with neuroblastic tumors having 535 MR T2-weighted sequences (486 sequences at diagnosis and 49 after finalization of the first phase of chemotherapy). The automatic segmentation algorithm was based on a nnU-Net architecture developed within the PRIMAGE project. For comparison, the segmentation masks were manually edited by an expert radiologist, and the time for the manual editing was recorded. Different overlaps and spatial metrics were calculated to compare both masks. RESULTS: The median Dice Similarity Coefficient (DSC) was high 0.997; 0.944-1.000 (median; Q1-Q3). In 18 MR sequences (6%), the net was not able neither to identify nor segment the tumor. No differences were found regarding the MR magnetic field, type of T2 sequence, or tumor location. No significant differences in the performance of the net were found in patients with an MR performed after chemotherapy. The time for visual inspection of the generated masks was 7.9 ± 7.5 (mean ± Standard Deviation (SD)) seconds. Those cases where manual editing was needed (136 masks) required 124 ± 120 s. CONCLUSIONS: The automatic CNN was able to locate and segment the primary tumor on the T2-weighted images in 94% of cases. There was an extremely high agreement between the automatic tool and the manually edited masks. This is the first study to validate an automatic segmentation model for neuroblastic tumor identification and segmentation with body MR images. The semi-automatic approach with minor manual editing of the deep learning segmentation increases the radiologist's confidence in the solution with a minor workload for the radiologist.

Anti-GD2 Antibody Dinutuximab Beta and Low-Dose Interleukin 2 After Haploidentical Stem-Cell Transplantation in Patients With Relapsed Neuroblastoma: A Multicenter, Phase I/II Trial.

PURPOSE: Patients with relapsed high-risk neuroblastoma (rHR-NB) have a poor prognosis. We hypothesized that graft-versus-neuroblastoma effects could be elicited by transplantation of haploidentical stem cells (haplo-SCT) exploiting cytotoxic functions of natural killer cells and their activation by the anti-GD2 antibody dinutuximab beta (DB). This phase I/II trial assessed safety, feasibility, and outcomes of immunotherapy with DB plus subcutaneous interleukin-2 (scIL2) after haplo-SCT in patients with rHR-NB. METHODS: Patients age 1-21 years underwent T-/B-cell-depleted haplo-SCT followed by DB and scIL2. The primary end point 'success of treatment' encompassed patients receiving six cycles, being alive 180 days after end of trial treatment without progressive disease, unacceptable toxicity, acute graft-versus-host-disease (GvHD) ≥grade 3, or extensive chronic GvHD. RESULTS: Seventy patients were screened, and 68 were eligible for immunotherapy. Median number of DB cycles was 6 (range, 1-9). Median number of scIL2 cycles was 3 (1-6). The primary end point was met by 37 patients (54.4%). Median observation time was 7.8 years. Five-year event-free survival (EFS) and overall survival from start of trial treatment were 43% (95% CI, 31 to 55) and 53% (95% CI, 41 to 65), respectively. Five-year EFS among patients in complete remission (CR; 52%; 95% CI, 31 to 69) or partial remission (44%; 95% CI, 27 to 60) before immunotherapy were significantly better compared with patients with nonresponse/mixed response/progressive disease (13%; 95% CI, 1 to 42; P = .026). Overall response rate in 43 patients with evidence of disease after haplo-SCT was 51% (22 patients), with 15 achieving CR (35%). Two patients developed GvHD grade 2 and 3 each. No unexpected adverse events occurred. CONCLUSION: DB therapy after haplo-SCT in patients with rHR-NB is feasible, with low risk of inducing GvHD, and results in long-term remissions likely attributable to increased antineuroblastoma activity by donor-derived effector cells.

Genomic ALK alterations in primary and relapsed neuroblastoma.

BACKGROUND: Genomic alterations of the anaplastic lymphoma kinase gene (ALK) occur recurrently in neuroblastoma, a pediatric malignancy of the sympathetic nervous system. However, information on their development over time has remained sparse. METHODS: ALK alterations were assessed in neuroblastomas at diagnosis and/or relapse from a total of 943 patients, covering all stages of disease. Longitudinal information on diagnostic and relapsed samples from individual patients was available in 101 and 102 cases for mutation and amplification status, respectively. RESULTS: At diagnosis, ALK point mutations occurred in 10.5% of all cases, with highest frequencies in stage 4 patients <18 months. At relapse, ALK alteration frequency increased by 70%, both in high-risk and non-high-risk cases. The increase was most likely due to de novo mutations, frequently leading to R1275Q substitutions, which are sensitive to pharmacological ALK inhibition. By contrast, the frequency of ALK amplifications did not change over the course of the disease. ALK amplifications, but not mutations, were associated with poor patient outcome. CONCLUSIONS: The considerably increased frequency of ALK mutations at relapse and their high prevalence in young stage 4 patients suggest surveying the genomic ALK status regularly in these patient cohorts, and to evaluate ALK-targeted treatment also in intermediate-risk patients.

Epidemiology and Characteristics of Gastric Carcinoma in Childhood-An Analysis of Data from Population-Based and Clinical Cancer Registries.

(1) Background: Gastric carcinoma is an exceptionally rare tumor in childhood. Little is known about the etiology, epidemiology, and clinical features of pediatric gastric carcinomas. This analysis aimed to fill this gap by increasing knowledge about the occurrence of gastric carcinoma in childhood. (2) Material and methods: Data from gastric carcinoma cases diagnosed between 2000 and 2017/2018 were retrieved from the Surveillance, Epidemiology, and End Results Program (SEER) and the German Center for Cancer Registry Data. Data from patients <20 years of age were analyzed for patient- and tumor-related characteristics. In addition, clinical data from patients with gastric carcinoma registered in the German Registry for Rare Pediatric Tumors (STEP) were analyzed for diagnostics, therapy, and outcome. (3) Results: Ninety-one cases of gastric carcinoma, mainly in adolescents, were identified in the epidemiologic cancer registries. Among patients with recorded staging data, advanced tumor stages were common (66.7%). Within the follow-up period covered, 63.7% of patients with clinical follow-up data died. Eight pediatric patients with gastric carcinoma were enrolled in the STEP registry, among whom two were patients with hereditary CDH1 mutations and another was a patient with Peutz−Jeghers syndrome. Three patients were found to have distinctly decreased immunoglobulin concentrations. All four patients in whom complete resection was achieved remained in remission. Three of the other four patients died despite multimodal therapy. (4) Conclusions: A combination of Helicobacter pylori infection and tumor predisposition and/or immunodeficiency appears to promote the development of gastric carcinoma in childhood. While patients with localized disease stages have a good chance of achieving durable remission through complete resection, patients with stage IV carcinomas face a dismal prognosis, highlighting the need to develop new strategies such as mutation-guided treatments.

Overcoming inter-observer planning variability in target volume contouring and dose planning for high-risk neuroblastoma - a European multicenter effort of the SIOPEN radiotherapy committee.

BACKGROUND AND PURPOSE: To establish an international quality standard for contouring and planning for high-risk neuroblastoma within the prospective High-Risk Neuroblastoma Study 2 of SIOP-Europe-Neuroblastoma (SIOPEN HR-NBL2), which includes a randomized question on dose escalation for residual disease. MATERIALS AND METHODS: Data on four patients with high-risk neuroblastoma were selected and distributed to the radiotherapy committee of the HR-NBL2 study for independent contouring and planning. Differences in contouring were analyzed using apparent and kappa-corrected agreement. Plans were analyzed regarding the dose-volume histogram metrics. Results were discussed among experts and agreement was obtained. RESULTS: Substantial agreement was found for contouring of the heart (0.64), liver (0.70), left lung (0.74), and right lung (0.74). For contouring of the gastrointestinal tract (0.54), left kidney (0.60), and right kidney (0.59) moderate agreement was obtained. For target volume delineation, agreement for preoperative tumour extent was moderate (0.42), for CTV fair (0.35) and only low (0.06) for residual tumour, respectively. The dose planning strategies appeared to be relatively homogeneous among all experts. CONCLUSION: Considerable variability was found for the delineation of target volumes, particularly the boost volume, whereas the contouring of the organs at risk and the planning strategy were reasonably consistent. In order to obtain reliable results from the randomized HR-NBL2 trial, standardization of target volume delineation based on adequate imaging is crucial.

Molecular diagnostics enables detection of actionable targets: the Pediatric Targeted Therapy 2.0 registry.

BACKGROUND: Precision oncology requires diagnostic accuracy and robust detection of actionable alterations. The Pediatric Targeted Therapy (PTT) 2.0 program aims at improving diagnostic accuracy by addition of molecular analyses to the existing histological diagnosis and detection of actionable alterations for relapsed paediatric oncology patients, in cases with limited availability of tumour material. METHODS: Paediatric patients diagnosed with relapse or progression of a central nervous system tumour (n = 178), a sarcoma (n = 41) or another solid tumour (n = 44) were included. DNA methylation array, targeted gene panel sequencing on tumour and blood (130 genes), RNA sequencing in selected cases and a pathway-specific immunohistochemistry (IHC) panel were performed using limited formalin-fixed paraffin embedded tissue from any disease episode available. The clinical impact of reported findings was assessed by a serial questionnaire-based follow-up. RESULTS: Integrated molecular diagnostics resulted in refined or changed diagnosis in 117/263 (44%) tumours. Actionable targets were detected in 155/263 (59%) cases. Constitutional DNA variants with clinical relevance were identified in 16/240 (7%) of patients, half of which were previously unknown. Clinical follow-up showed that 26/263 (10%) of patients received mechanism-of-action based treatment matched to the molecular findings. CONCLUSION: Next-generation diagnostics adds robust and relevant information on diagnosis, actionable alterations and cancer predisposition syndromes even when tissue from the current disease episode is limited.

Upward Lightning at the Gaisberg Tower: The Larger-Scale Meteorological Influence on the Triggering Mode and Flash Type.

Upward lightning is rarer than downward lightning and requires tall (100+ m) structures to initiate. It may be either self-initiated or triggered by other lightning discharges. While conventional lightning location systems (LLSs) detect most of the upward lightning flashes superimposed by pulses or return strokes, they miss a specific flash type that consists only of a continuous current. Globally, only few specially instrumented towers can record this flash type. The proliferation of wind turbines in combination with damages from upward lightning necessitates an improved understanding under which conditions self-initiated upward lightning and the continuous-current-only subtype occur. This study uses a random forest machine learning model to find the larger-scale meteorological conditions favoring the occurrence of the different phenomena. It combines ground truth lightning current measurements at the specially instrumented tower at Gaisberg mountain in Austria with variables from larger-scale meteorological reanalysis data (ERA5). These variables reliably explain whether upward lightning is self-initiated or triggered by other lightning discharges. The most important variable is the height of the -10°C isotherm above the tall structure: the closer it is, the higher is the probability of self-initiated upward lightning. For the different flash types, this study finds a relationship to the larger-scale electrification conditions and the LLS-detected lightning situation in the vicinity. Lower amounts of supercooled liquid water, solid, and liquid differently sized particles and no LLS-detected lightning events nearby favor the continuous-current-only subtype compared to the other subtypes, which preferentially occur with LLS-detected lightning events within 3 km from the Gaisberg Tower.

Efficacy and Feasibility of Proton Beam Therapy in Relapsed High-Risk Neuroblastoma-Experiences from the Prospective KiProReg Registry.

BACKGROUND: Despite an intensive multimodal treatment approach, approximately 50% of high-risk (HR) neuroblastoma (NB) patients experience progression. Despite the advances in targeted therapy, high-dose chemotherapy, and other systemic treatment options, radiation therapy (RT) to sites of relapsed disease can be an option to reduce tumor burden and improve chance for disease control. METHODS: Patients who received salvage irradiation with proton beam therapy (PBT) for local or metastatic relapse of HR NB within the prospective registry trials KiProReg and ProReg were eligible for this retrospective analysis. Data on patient characteristics, multimodality therapy, adverse events, and oncologic endpoints were evaluated. Adverse events were assessed before, during, and after PBT according to common terminology criteria for adverse events (CTCAE) V4.0. RESULTS: Between September 2013 and September 2020, twenty (11 male; 9 female) consecutive patients experiencing local (N = 9) or distant recurrence (N = 25) were identified for this analysis. Distant recurrences included osteomedullary (N = 11) or CNS lesions (N = 14). Salvage therapy consisted of re-induction chemo- or chemo-immuno-therapy (N = 19), surgery (N = 6), high-dose chemotherapy and stem cell transplantation (N = 13), radiation (N = 20), and concurrent systemic therapy. Systemic therapy concurrent to RT was given to six patients and included temozolomide (N = 4), carboplatine (N = 1), or anaplastic lymphoma kinase tyrosine kinase inhibitors (ALK-TKI) (N = 1). A median dose of 36 Gy was applied to the 34 recurrent sites. Local RT was applied to 15 patients, while five patients, received craniospinal irradiation for CNS relapse. After a median follow-up (FU) of 20 months (4-66), the estimated rate for local control, distant metastatic free survival, and overall survival at 3 years was 68.0%, 37.9%, and 61.6%, respectively. During RT, ten patients (50%) presented with a higher-grade acute hematologic adverse event. Late higher-grade sequelae included transient myelitis with transverse section (N = 2) and secondary malignancy outside of the RT field (N = 1). CONCLUSION: Our study demonstrates the efficacy and safety of RT/PBT for recurrent HR NB in a multimodality second-line approach. To better define the role of RT for these patients, prospective studies would be desirable.

Presenting features of neuroblastoma with spinal canal invasion. A prospective study of the International Society of Pediatric Oncology Europe - Neuroblastoma (SIOPEN).

Introduction: Between 5 and 15% of children with neuroblastoma (NB) present with or develop spinal canal invasion (SCI). The majority of these children have symptoms of epidural compression of spinal cord and/or spinal nerves. Treatment of NB-SCI is considered an emergency but its modalities are not yet well-established. Independently of treatment, NB-SCI may result in significant long-term disabilities. We report on the first prospective study of NB-SCI focused on presenting characteristics of both symptomatic and asymptomatic patients and correlation between SCI-related symptoms and imaging features. Materials and methods: This SIOPEN prospective NB-SCI study opened in June 2014. Patient data including SCI symptoms evaluated by standardized measures and spinal cord imaging studies were collected for each patient. For the purpose of this study data entry was locked on July 2021. Results: Of the 208 NB-SCI patients registered, 196 were evaluable for this analysis of whom 67% were symptomatic and 33% asymptomatic. Median age was 11 months. The thorax was the commonest primary tumor site. The median intervals between initial symptoms and diagnosis and between first medical visit and diagnosis were 14 and 3 days, respectively. The was no statistical difference in frequency of presenting characteristics between symptomatic and asymptomatic patients. Presenting features of NB-SCI patients differed from other NBs for older median age, prevalence of thoracic vs. abdominal primary site, prevalence of localized vs. metastatic disease and lower incidence of MYCN gene amplification. The most common SCI features were motor deficit in the younger and pain in the older patients that correlated on imaging with both transverse and longitudinal extent but not with the level of intraspinal tumor. Spinal cord T2-hyperintensity was more frequently detected in symptomatic patients (not significant). Conclusion: This prospective study confirms that children with NB-SCI differ from NBs without SCI. Compared to previous studies, it provides more detailed information regarding presenting symptoms, time intervals between SCI symptoms, medical visit and diagnosis, and correlations between symptoms and imaging features.

Reliable assessment of telomere maintenance mechanisms in neuroblastoma.

BACKGROUND: Telomere maintenance mechanisms (TMM) are a hallmark of high-risk neuroblastoma, and are conferred by activation of telomerase or alternative lengthening of telomeres (ALT). However, detection of TMM is not yet part of the clinical routine, and consensus on TMM detection, especially on ALT assessment, remains to be achieved. METHODS: Whole genome sequencing (WGS) data of 68 primary neuroblastoma samples were analyzed. Telomere length was calculated from WGS data or by telomere restriction fragment analysis (n = 39). ALT was assessed by C-circle assay (CCA, n = 67) and detection of ALT-associated PML nuclear bodies (APB) by combined fluorescence in situ hybridization and immunofluorescence staining (n = 68). RNA sequencing was performed (n = 64) to determine expression of TERT and telomeric long non-coding RNA (TERRA). Telomerase activity was examined by telomerase repeat amplification protocol (TRAP, n = 15). RESULTS: Tumors were considered as telomerase-positive if they harbored a TERT rearrangement, MYCN amplification or high TERT expression (45.6%, 31/68), and ALT-positive if they were positive for APB and CCA (19.1%, 13/68). If all these markers were absent, tumors were considered TMM-negative (25.0%, 17/68). According to these criteria, the majority of samples were classified unambiguously (89.7%, 61/68). Assessment of additional ALT-associated parameters clarified the TMM status of the remaining seven cases with high likelihood: ALT-positive tumors had higher TERRA expression, longer telomeres, more telomere insertions, a characteristic pattern of telomere variant repeats, and were associated with ATRX mutations. CONCLUSIONS: We here propose a workflow to reliably detect TMM in neuroblastoma. We show that unambiguous classification is feasible following a stepwise approach that determines both, activation of telomerase and ALT. The workflow proposed in this study can be used in clinical routine and provides a framework to systematically and reliably determine telomere maintenance mechanisms for risk stratification and treatment allocation of neuroblastoma patients.

Adrenocortical Tumors and Pheochromocytoma/Paraganglioma Initially Mistaken as Neuroblastoma-Experiences From the GPOH-MET Registry.

In children and adolescents, neuroblastoma (NBL), pheochromocytoma (PCC), and adrenocortical tumors (ACT) can arise from the adrenal gland. It may be difficult to distinguish between these three entities including associated extra-adrenal tumors (paraganglioma, PGL). Precise discrimination, however, is of crucial importance for management. Biopsy in ACT or PCC is potentially harmful and should be avoided whenever possible. We herein report data on 10 children and adolescents with ACT and five with PCC/PGL, previously mistaken as NBL. Two patients with adrenocortical carcinoma died due to disease progression. Two (2/9, missing data in one patient) patients with a final diagnosis of ACT clearly presented with obvious clinical signs and symptoms of steroid hormone excess, while seven patients did not. Blood analyses indicated increased levels of steroid hormones in one additional patient; however, urinary steroid metabolome analysis was not performed in any patient. Two (2/10) patients underwent tumor biopsy, and in two others tumor rupture occurred intraoperatively. In 6/10 patients, ACT diagnosis was only established by a reference pediatric pathology laboratory. Four (4/5) patients with a final diagnosis of PCC/PGL presented with clinical signs and symptoms of catecholamine excess. Urine tests indicated possible catecholamine excess in two patients, while no testing was carried out in three patients. Measurements of plasma metanephrines were not performed in any patient. None of the five patients with PCC/PGL received adrenergic blockers before surgery. In four patients, PCC/PGL diagnosis was established by a local pathologist, and in one patient diagnosis was revised to PGL by a pediatric reference pathologist. Genetic testing, performed in three out of five patients with PCC/PGL, indicated pathogenic variants of PCC/PGL susceptibility genes. The differential diagnosis of adrenal neoplasias and associated extra-adrenal tumors in children and adolescents may be challenging, necessitating interdisciplinary and multidisciplinary efforts. In ambiguous and/or hormonally inactive cases through comprehensive biochemical testing, microscopical complete tumor resection by an experienced surgeon is vital to preventing poor outcome in children and adolescents with ACT and/or PCC/PGL. Finally, specimens need to be assessed by an experienced pediatric pathologist to establish diagnosis.