Influence of image-defined risk factors on the outcome of patients with localised neuroblastoma. A report from the LNESG1 study of the European International Society of Paediatric Oncology Neuroblastoma Group

Children's Oncology Group's 2023 blueprint for research: Surgery

Surgery plays a crucial role in the treatment of children with solid malignancies. A well-conducted operation is often essential for cure. Collaboration with the primary care team is important for determining if and when surgery should be performed, and if performed, an operation must be done in accordance with well-established standards. The long-term consequences of surgery also need to be considered. Indications and objectives for a procedure vary. Providing education and developing and analyzing new research protocols that include aims relevant to surgery are key objectives of the Surgery Discipline of the Children's Oncology Group. The critical evaluation of emerging technologies to ensure safe, effective procedures is another key objective. Through research, education, and advancing technologies, the role of the pediatric surgeon in the multidisciplinary care of children with solid malignancies will continue to evolve.

Gadolinium-based contrast media does not improve the staging of neuroblastoma image-defined risk factors at diagnosis

BACKGROUND

Neuroblastoma risk stratification relies on prognostic risk factors and image-defined risk factors (IDRFs). Evaluating neuroblastoma typically involves magnetic resonance imaging (MRI) with gadolinium-based contrast media (GBCM, "contrast"). However, there are concerns regarding adverse effects and cost of GBCM. We aimed to assess the impact of intravenous GBCM on interobserver agreement for neuroblastoma staging on baseline MRI.

PROCEDURE

We reviewed baseline MRI scans of 50 children with abdominopelvic neuroblastomas confirmed by histopathology. Duplicate sets of images were created, with post-contrast T1-weighted sequences removed from one set. Four pediatric radiologists independently analyzed the scans in a randomized manner. They recorded primary tumor size, presence of IDRFs, and metastatic lesions. Agreement among the reviewers was measured using kappa and Fleiss kappa statistics.

RESULTS

Mean age of included children was 3.3 years (range: 0.01-14.9 years), and 20 [40%] were females. Mean tumor size was 5.7 cm in greatest axial diameter. Pre-contrast versus post-contrast MRI showed excellent agreement for tumor measurement. Overlapping confidence intervals (CIs) were seen in nearly all categories of interobserver agreement on the presence or absence of individual IDRFs, with agreement ranging from poor to substantial, regardless of the presence of contrast. The overall interobserver agreement on the presence of at least one IDRF was substantial with contrast (kappa = .63; 95% CI: .52-.75) and moderate without contrast (kappa = .5; 95% CI: .39-.61); although the overlapping CIs suggest a lack of meaningful difference. Similarly, interobserver agreement on the presence or absence of individual sites of metastatic disease ranged from poor to substantial. The interobserver agreement on the overall determination of presence of metastatic disease was fair with contrast (kappa = .49; 95% CI: .38-.61) and moderate without contrast (kappa = .71; 95% CI: .59-.826).

CONCLUSIONS

Contrast does not improve tumor size measurement or radiologist agreement on the presence or absence of IDRFs or metastatic disease in children with newly diagnosed neuroblastoma.

[Surgery for abdominal neuroblastoma in children]

This review is devoted to surgical approach for neurogenic tumors in children. The authors discuss epidemiological data, history of surgical approaches, preoperative imaging and risk factors. A special attention is paid to the influence of surgical interventions for various neuroblastomas on overall and event-free survival in pediatric population, as well as the most common surgical complications and modern approaches to their treatment.

The role of surgery in the treatment of neuroblastoma metastases at rare sites

PURPOSE

Treatment of neuroblastoma metastases usually consists of chemotherapy and irradiation. However, in selected cases, surgical treatment is also indicated. In this study, we present three cases of patients with neuroblastoma metastases at rare sites that underwent surgery.

MATERIALS AND METHODS

We retrospectively analyzed data of patients who underwent surgery for neuroblastoma at our department of Pediatric Surgery and Pediatric Urology at the University Children's Hospital in Tuebingen and selected those patients who had surgery explicitly for a metastasis.

RESULTS

Between 2002 and 2020, 277 children underwent surgical treatment for neuroblastoma. Three cases with metastases at exceptional sites are presented here after therapy according to protocols. One patient had a penile metastasis and received surgery including a plastic reconstruction. The patient showed no signs of erectile or urinary dysfunction at follow-up. Another patient had a metastasis in the proximal ulna, which remained vital even after exhausted treatment after two relapses. Afterward there was no restriction of movement of the extremity. The third patient had, amongst others, metastases to the pancreatic body and to the liver. Both were surgically removed during primary tumor resection. This patient died after local tumor relapse. The other two patients showed no evidence of tumor relapse after a follow-up of 18 and 17 months, respectively.

CONCLUSION

Although children with neuroblastoma often present with metastases, there is no recommendation for surgical treatment other than diagnostic biopsies. In case of persistence of metastasis or after exhaustion of high-risk therapy, surgical resection must be considered.

Critical elements of pediatric neuroblastoma surgery

Neuroblastoma (NB) is the most common solid extracranial malignancy of childhood with an incidence of 1 per 100,000 in the United States compromising approximately 10 % of childhood cancer. Unfortunately, patients with high-risk NG continue to have long-term survival less than 50 %. Both Children's Oncology Group and the International Society of Paediatric Oncology have demonstrated the important role of surgery in the treatment of high-risk NB. Herein, we compose the results of an extensive literature review as well as expert opinion from leaders in pediatric surgical oncology, to present the critical elements of effective surgery for high-risk neuroblastoma.

Combined Metabolic and Functional Tumor Volumes on [18F]FDG-PET/MRI in Neuroblastoma Using Voxel-Wise Analysis

PURPOSE

The purpose of our study was to evaluate the association between the [18F]FDG standard uptake value (SUV) and the apparent diffusion coefficient (ADC) in neuroblastoma (NB) by voxel-wise analysis.

METHODS

From our prospective observational PET/MRI study, a subcohort of patients diagnosed with NB with both baseline imaging and post-chemotherapy imaging was further investigated. After registration and tumor segmentation, metabolic and functional tumor volumes were calculated from the ADC and SUV values using dedicated software allowing for voxel-wise analysis. Under the mean of thresholds, each voxel was assigned to one of three virtual tissue groups: highly vital (v) (low ADC and high SUV), possibly low vital (lv) (high ADC and low SUV), and equivocal (e) with high ADC and high SUV or low ADC and low SUV. Moreover, three clusters were generated from the total tumor volumes using the method of multiple Gaussian distributions. The Pearson's correlation coefficient between the ADC and the SUV was calculated for each group.

RESULTS

Out of 43 PET/MRIs in 21 patients with NB, 16 MRIs in 8 patients met the inclusion criteria (PET/MRIs before and after chemotherapy). The proportion of tumor volumes were 26%, 36%, and 38% (v, lv, e) at baseline, 0.03%, 66%, and 34% after treatment in patients with response, and 42%, 25%, and 33% with progressive disease, respectively. In all clusters, the ADC and the SUV correlated negatively. In the cluster that corresponded to highly vital tissue, the ADC and the SUV showed a moderate negative correlation before treatment (R = -0.18; p < 0.0001) and the strongest negative correlation after treatment (R = -0.45; p < 0.0001). Interestingly, only patients with progression (n = 2) under therapy had a relevant part in this cluster post-treatment.

CONCLUSION

Our results indicate that voxel-wise analysis of the ADC and the SUV is feasible and can quantify the different quality of tissue in neuroblastic tumors. Monitoring ADCs as well as SUV levels can quantify tumor dynamics during therapy.

Development and validation of a 21-gene prognostic signature in neuroblastoma

Survival outcomes for patients with neuroblastoma vary markedly and reliable prognostic markers and risk stratification tools are lacking. We sought to identify and validate a transcriptomic signature capable of predicting risk of mortality in patients with neuroblastoma. The TARGET NBL dataset (n = 243) was used to develop the model and two independent cohorts, E-MTAB-179 (n = 478) and GSE85047 (n = 240) were used as validation sets. EFS was the primary outcome and OS was the secondary outcome of interest for all analysis. We identified a 21-gene signature capable of stratifying neuroblastoma patients into high and low risk groups in the E-MTAB-179 (HR 5.87 [3.83-9.01], p < 0.0001, 5 year AUC 0.827) and GSE85047 (HR 3.74 [2.36-5.92], p < 0.0001, 5 year AUC 0.815) validation cohorts. Moreover, the signature remained independent of known clinicopathological variables, and remained prognostic within clinically important subgroups. Further, the signature was effectively incorporated into a risk model with clinicopathological variables to improve prognostic performance across validation cohorts (Pooled Validation HR 6.93 [4.89-9.83], p < 0.0001, 5 year AUC 0.839). Similar prognostic utility was also demonstrated with OS. The identified signature is a robust independent predictor of EFS and OS outcomes in neuroblastoma patients and can be combined with clinically utilized clinicopathological variables to improve prognostic performance.

Radiomic-based machine learning model for predicting the surgical risk in children with abdominal neuroblastoma

Background

Preoperative imaging assessment of surgical risk is very important for the prognosis of these children. To develop and validate a radiomics-based machine learning model based on the analysis of radiomics features to predict surgical risk in children with abdominal neuroblastoma (NB).

Methods

A retrospective study was conducted from April 2019 to March 2021 among 74 children with abdominal NB. A total of 1874 radiomic features in MR images were extracted from each patient. Support vector machines (SVMs) were used to establish the model. Eighty percent of the data were used as the training set to optimize the model, and 20% of the data were used to validate its accuracy, sensitivity, specificity and area under the curve (AUC) to verify its effectiveness.

Results

Among the 74 children with abdominal NB, 55 (65%) had surgical risk and 19 (35%) had no surgical risk. A t test and Lasso identified that 28 radiomic features were associated with surgical risk. After developing an SVM-based model using these features, predictions were made about whether children with abdominal NB had surgical risk. The model achieved an AUC of 0.94 (a sensitivity of 0.83 and a specificity of 0.80) with 0.890 accuracy in the training set and an AUC of 0.81 (a sensitivity of 0.73 and a specificity of 0.82) with 0.838 accuracy in the test set.

Conclusions

Radiomics and machine learning can be used to predict the surgical risk in children with abdominal NB. The model based on 28 radiomic features established by SVM showed good diagnostic efficiency.

Association of image-defined risk factors with clinical features, tumor biology, and outcomes in neuroblastoma: a single-center retrospective study

Image-defined risk factors (IDRF) in neuroblastoma have been developed to predict tumor resectability and surgical complications; however, the potential prognostic value of IDRF in neuroblastoma has been variably reported. Previous studies did not report the IDRF status separately from the International Neuroblastoma Risk Group (INRG) stage. Moreover, the association between IDRF and clinical and pathological factors has not been discussed further. In this retrospective study, we investigated the clinical and biological features of neuroblastoma at different INRG stages based on IDRF. Event-free survival (EFS) and overall survival (OS) related to the INRG stage were analyzed using log-rank tests, and the prognostic value of the IDRF number and type was also evaluated. Among 72 patients, 182 IDRF at diagnosis were found in 79.2%. The distribution of the INRG stages was 10 L1 (13.9.0%), 25 L2 (34.7%), and 37 M/MS (51.4%). Patients with stage M/Ms had a larger tumor volume, a higher percentage of age ≥ 18 months, elevated lactate dehydrogenase (LDH) level, elevated ferritin level, and a higher percentage of COG high-risk compared with stage L1 and L2 patients. EFS and OS were similar for stage L1 and L2 tumors but were significantly poorer for metastatic disease. However, EFS (P = 0.06) and OS (P = 0.07) were similar for IDRF-negative and positive neuroblastomas. Patients with stage M/Ms with IDRF-positive had poorer EFS (P = 0.001) and OS (P < 0.001) compared with patients in stage L2. An IDRF ≥ 4, vascular IDRF, and infiltrative IDRF of the tumor were significant indicators of poor prognosis.   Conclusion: Our study indicates that increasing the INRG stages based on IDRF is associated with various unfavorable clinical features of neuroblastoma. The principal determinant of survival in neuroblastoma is the presence of metastatic disease more than IDRF alone at diagnosis. Both the number and type of IDRF have important clinical significance in the protocol planning of neuroblastoma, rather than just considering the absence or presence of IDRF. What is Known: • The International Neuroblastoma Risk Group Staging System (INRGSS) now employs image-defined risk factors (IDRFs) to stratify and stage disease. • The presence of IDRF at diagnosis are associated with higher rates of operative complications and incomplete surgical resection. What is New: • The principal determinant of survival from neuroblastoma is the presence of metastatic disease at diagnosis, more than IDRF alone. • IDRF number and type should also be considered during the diagnosis and treatment planning of neuroblastoma, rather than just considering the absence or presence of IDRF.

Segmental chromosomal aberrations as the poor prognostic factor in children over 18 months with stage 3 neuroblastoma without MYCN amplification

Introduction

Patients with stage 3 neuroblastoma (NBL) according to International Neuroblastoma Staging System (INSS) without MYCN amplification represent a heterogenous group with respect to disease presentation and prognosis.

Methods

Retrospective analysis of 40 stage 3 patients with NBL without MYCN amplification was performed. The prognostic value of age at diagnosis (under 18 vs over 18 months), International Neuroblastoma Pathology Classification (INPC) diagnostic category and presence of segmental or numerical chromosomes aberrations were evaluated, as well as biochemical markers. Array comparative genomic hybridization (aCGH) for analyzing copy number variations and Sanger sequencing for ALK point mutations were done.

Results

In 12 patients (two patients under 18 months), segmental chromosomal aberrations (SCA) were found and numerical chromosomal aberrations (NCA) were found in 16 patients (14 patients under 18 months). In children over 18 months SCA were more common (p=0.0001). Unfavorable pathology was significantly correlated with SCA genomic profile (p=0.04) and age over 18 months (p=0.008). No therapy failures occurred in children with NCA profile over or under 18 months or in children under 18 months, irrespective of pathology and CGH results. Three treatment failures occurred in the SCA group, in one patient CGH profile was not available. For the whole group at 3, 5 and 10-year OS and DFS were 0.95 (95% CI 0.81-0.99), 0.91 (95% CI 0.77-0.97) and 0.91 (95% CI 0.77-0.97), and 0.95 (95% CI 0.90-0.99), 0.92 (95% CI 0.85-0.98) and 0.86 (95% CI 0.78-0.97), respectively. DFS was significantly lower in the SCA group than in the NCA group (3-years, 5-years, and 10-years DFS 0.92 (95% CI 0.53-0.95), 0.80 (95% CI 0.40-0.95) and 0.60 (95% CI 0.16-0.87) vs 1.0, 1.0 and 1.0, respectively, p=0.005).

Conclusions

The risk of treatment failure was higher in patients with SCA profile, but only in patients over 18 months. All relapses occurred in children having obtained the complete remission, with no previous radiotherapy. In patients over 18 months, SCA profile should be taken into consideration for therapy stratification as it increases the risk of relapse and this group may require more intensive treatment.

Laparoscopic approach of pediatric adrenal tumors

PURPOSE

To analyze the role of laparoscopic surgery for the management of pediatric adrenal tumors (AT).

METHODS

Retrospective analysis of children diagnosed with AT, operated laparoscopically during 2003-2020. The strategy differed according to tumor extension. AT < 6 cm were resected. Locally advanced tumors (L2) or > 6 cm were biopsied.

RESULTS

N = 28. Complete tumor resection (R0) in 20 (71%), tumor biopsy in 8 (R2). Age (median): 28.8 months (2 months-18 years). 14/28 left-sided, 2 bilateral. Median operating time: 78 min (45-180). Mean tumor size (for resections): 4 cm (2.5-6). Tumor pathology: neuroblastoma (n = 17), Ganglioneuroma (n = 7), Adrenocortical carcinoma (n = 1), Osteosarcoma metastasis (n = 1), Pheochromocytoma (n = 1), Venous malformation (n = 1). Mean hospital stay: 2.5 days (1-3). Mean follow up: 65.5 months (24-192). Overall survival and event-free survival were 86 and 75%, respectively (5 years event-free survival for neuroblastoma: 33% [intermediate risk], 16.6% [high risk]. No surgery-related mortality.

CONCLUSION

Laparoscopic surgery for adrenal tumors is safe. Laparoscopic biopsy is useful for unresectable tumors when a percutaneous approach is not possible. With the proposed selection criteria, the laparoscopic approach should be the first option for resection of small and localized AT in pediatrics.

Advances in the treatment of pediatric solid tumors: A 50-year perspective

In the United States, more than 10 000 cancers occur annually in children aged 0-14 years, and more than 5000 in adolescents aged 15-19. In the last 50 years, significant advances have been made in imaging, molecular pathology, stage and risk assessment, surgical approach, multidisciplinary treatment, and survival for pediatric solid tumors (particularly neuroblastoma, Wilms tumor, rhabdomyosarcoma, and hepatoblastoma). Moreover, the molecular driver for fibrolamellar hepatocellular carcinoma, which occurs in adolescence and young adulthood, has been identified.

Minimally invasive surgery for neuroblastic tumours: A SIOPEN multicentre study: Proposal for guidelines

INTRODUCTION

Surgery plays a key role in the management of Neuroblastic tumours (NB), where the standard approach is open surgery, while minimally invasive surgery (MIS) may be considered an option in selected cases. The indication(s) and morbidity of MIS remain undetermined due to small number of reported studies. The aim of this study was to critically address the contemporary indications, morbidity and overall survival (OS) and propose guidelines exploring the utility of MIS for NB.

MATERIALS & METHODS

A SIOPEN study where data of patients with NB who underwent MIS between 2005 and 2018, including demographics, tumour features, imaging, complications, follow up and survival, were extracted and then analysed.

RESULTS

A total of 222 patients from 16 centres were identified. The majority were adrenal gland origin (54%) compared to abdominal non-adrenal and pelvic (16%) and thoracic (30%). Complete and near complete macroscopic resection (>95%) was achieved in 95%, with 10% of cases having conversion to open surgery. Complications were reported in 10% within 30 days of surgery. The presence of IDRF (30%) and/or tumour volume >75 ml were risk factors for conversion and complications in multivariate analysis. Overall mortality was 8.5%.

CONCLUSIONS

MIS for NB showed that it is a secure approach allowing more than 95% resection. The presence of IDRFs was not an absolute contraindication for MIS. Conversion to open surgery and overall complication rates were low, however they become significant if tumour volume >75 mL. Based on these data, we propose new MIS guidelines for neuroblastic tumours.

Implication of Image-Defined Risk Factors for the Extent of Surgical Resection and Clinical Outcome in Patients with Pelvic Neuroblastoma

INTRODUCTION

 Pelvic neuroblastoma (NB) is a rare entity and occurs in 2 to 5% of all NBs. Surgery in the pelvic area is-even for the experienced oncological surgeon-technically challenging, as injuries of bladder and/or rectal innervation may carry lifelong consequences for the patient. Several studies have proven the impact of image-defined risk factors (IDRFs) for outcome, complications and extent of resection in NB; however, the specific role of IDRF in pelvic NB has not been investigated yet.

MATERIALS AND METHODS

 Patient charts were retrospectively evaluated for International Staging System stage, IDRF status, MYCN amplification, and outcome parameters.

RESULTS

 Between 2003 and 2019, 277 NBs were surgically resected in the department of pediatric surgery of Dr. von Hauner Children's Hospital. Out of these, 11 patients (3.9%) had pelvic NB. Evaluation of the preoperative imaging showed two patients without IDRF (stage L1) and eight patients in stage L2. One patient had stage M according to distant metastasis. Patients without IDRF underwent complete macroscopical resections, whereas complete tumor removal was not possible without mutilation in patients with IDRF. At time point of diagnosis, only patients with IDRF had functional neurological problems. Three patients developed perioperative complications; all of them had at least one IDRF. Three patients developed local recurrence during the course of the disease, all of them had at least one IDRF.

CONCLUSION

 Our results indicate on a preliminary level the importance of IDRF as a prognostic tool for surgical removal of pelvic NB.

The Relevance of Preoperative Identification of the Adamkiewicz Artery in Posterior Mediastinal Pediatric Tumors

Background

Injury to the artery of Adamkiewicz (AKA) during surgery may lead to spinal cord ischemia and severe neurologic complications. Posterior mediastinal tumors may be adjacent to AKA, but data on preoperative visualization of AKA in children are rare. This study analyzed the importance of identifying the AKA preoperatively by spinal digital subtraction angiography (DSA) in children with posterior mediastinal tumors for therapeutic procedure.

Methods

Between 2002 and 2021, 36 children with posterior mediastinal tumors were evaluated for surgery at the authors’ clinic. In 10 children with left-sided or bilateral tumor located at vertebral levels T8 to L1, spinal DSA was performed during preoperative workup to assess AKA. The patient and tumor characteristics as well as the diagnostic and therapeutic procedures were analyzed.

Results

The median age of the 10 children at examination was 69 months (range, 16–217 months). Three of the children were younger than 2 years. The tumor entities were neuroblastoma, ganglioneuroblastoma, ganglioneuroma, local relapse of a hepatocellular carcinoma, and neurofibroma. The AKA was identified in all cases, and proximity to the tumor was detected in four patients, three of whom had their planned surgery changed to irradiation. No complications occurred during spinal DSA or surgery.

Conclusions

In posterior mediastinal pediatric tumors, spinal DSA is a safe and reliable method for preoperative visualization of the AKA. It can show proximity to the tumor and guide the local therapy, thereby avoiding critical intra- and postoperative situations.

Improving Exposure Using Thoracoscopy for Apical Thoracic Neuroblastoma Encasing the Subclavian Vessels

Background: Posterolateral thoracotomy provides limited access to the thoracic apex that can result in poor visualization of subclavian vessels, their branches, and the brachial plexus. A thoracoscopic approach may overcome these limitations. Purpose: We report a thoracoscopic approach and associated technical challenges in resecting apical thoracic neuroblastoma encasing the subclavian artery. Methods: A single-institution retrospective chart review was performed (2018-2020) for patients undergoing thoracoscopic resection of apical neuroblastoma encasing the subclavian artery. Patient demographics, imaging, and hospital course were reviewed. Operative video recordings were assessed for exposure quality, technical challenges, and percentage of tumor resection. Patients were placed laterally, with three 5-mm ports triangulated to the apex. Dissection started at the tumor edge and followed along the vessel and branches. Results: Four patients (median age 2.7 years) underwent thoracoscopic apical neuroblastoma resection. Median length of stay was 2.5 days. One low-risk patient underwent resection for tumor growth during observation. One intermediate and 2 high-risk patients received neoadjuvant chemotherapy. Two patients continued having persistent vascular encasement, whereas in 1 patient the mass decreased in size and only abutted the subclavian and vertebral arteries. In 1 patient, tumor involved the brachial plexus, which was freed and preserved thoracoscopically. All cases had substantial tumor-feeding vessels branching from the subclavian artery. There was one conversion to open thoracotomy due to dense tumor adherence to the subclavian artery and vein. More than 95% resection was achieved in all cases. All patients had baseline Horner syndrome. No complications were reported. Conclusion: The thoracoscopic approach for resecting apical neuroblastoma provides optimal exposure and safe access in selected patients.

Association of image-defined risk factors with clinical features, histopathology, and outcomes in neuroblastoma

BACKGROUND

Clinical, molecular, and histopathologic features guide treatment for neuroblastoma, but obtaining tumor tissue may cause complications and is subject to sampling error due to tumor heterogeneity. We hypothesized that image-defined risk factors (IDRFs) would reflect molecular features, histopathology, and clinical outcomes in neuroblastoma.

METHODS

We performed a retrospective cohort study of 76 patients with neuroblastoma or ganglioneuroblastoma. Diagnostic CT scans were reviewed for 20 IDRFs, which were consolidated into five IDRF groups (involvement of multiple body compartments, vascular encasement, tumor infiltration of adjacent organs/structures, airway compression, or intraspinal extension). IDRF groups were analyzed for association with clinical, molecular, and histopathologic features of neuroblastoma.

RESULTS

Patients with more IDRF groups had a higher risk of surgical complications (OR = 3.1, p = 0.001). Tumor vascular encasement was associated with increased risk of surgical complications (OR = 5.40, p = 0.009) and increased risk of undifferentiated/poorly differentiated histologic grade (OR = 11.11, p = 0.013). Tumor infiltration of adjacent organs and structures was associated with decreased survival (HR = 8.90, p = 0.007), MYCN amplification (OR = 9.91, p = 0.001), high MKI (OR = 6.20, p = 0.003), and increased risk of International Neuroblastoma Staging System stage 4 disease (OR = 8.96, p < 0.001).

CONCLUSIONS

The presence of IDRFs at diagnosis was associated with high-risk clinical, molecular, and histopathologic features of neuroblastoma. The IDRF group tumor infiltration into adjacent organs and structures was associated with decreased survival. Collectively, these findings may assist surgical planning and medical management for neuroblastoma patients.

Role of image-defined risk factors in predicting surgical complications of localized neuroblastoma

PURPOSE

To explore the relationship between image-defined risk factors and surgical complications of localized neuroblastoma.

METHODS

We retrospectively evaluated 84 patients who met the inclusion criteria at our hospitals between June 2014 and June 2019. Patients' clinic data were collected and the common terminology criteria for adverse events were used to categorize complications as major (grade 3-4) or minor (grade 1-2).

RESULTS

Four (11.8%) out of 34 stage L1 patients and 15 (30.0%) out of 50 stage L2 patients had surgical complications (P < 0.05). Seventy patents underwent primary surgery, including all stage L1 patients and 36 stage L2 patients. There were no significant differences between the two groups regarding surgical complications or major surgical complications. Among stage L2 patients, 2 (5.6%) out of 36 who underwent primary surgery and 2 (14.3%) out of 14 who underwent secondary surgery had major surgical complications (P < 0.05). Complete tumor resection was achieved in 18 (50%) and 7 (50%) patients in each group (P > 0.05). The mean numbers of IDRFs were 2.06 and 4.29, respectively (P < 0.05).

CONCLUSIONS

Localized neuroblastoma patients with IDRFs have a greater surgical risk. And the number of IDRFs is not ignorable, especially in predicting major surgical complications.

Tailoring Therapy for Children With Neuroblastoma on the Basis of Risk Group Classification: Past, Present, and Future

For children with neuroblastoma, the likelihood of cure varies widely according to age at diagnosis, disease stage, and tumor biology. Treatments are tailored for children with this clinically heterogeneous malignancy on the basis of a combination of markers that are predictive of risk of relapse and death. Sequential risk-based, cooperative-group clinical trials conducted during the past 4 decades have led to improved outcome for children with neuroblastoma. Increasingly accurate risk classification and refinements in treatment stratification strategies have been achieved with the more recent discovery of robust genomic and molecular biomarkers. In this review, we discuss the history of neuroblastoma risk classification in North America and Europe and highlight efforts by the International Neuroblastoma Risk Group (INRG) Task Force to develop a consensus approach for pretreatment stratification using seven risk criteria including an image-based staging system-the INRG Staging System. We also update readers on the current Children's Oncology Group risk classifier and outline plans for the development of a revised 2021 Children's Oncology Group classifier that will incorporate INRG Staging System criteria to facilitate harmonization of risk-based frontline treatment strategies conducted around the globe. In addition, we discuss new approaches to establish increasingly robust, future risk classification algorithms that will further refine treatment stratification using machine learning tools and expanded data from electronic health records and the INRG Data Commons.

Age Dependency of the Prognostic Impact of Tumor Genomics in Localized Resectable MYCN-Nonamplified Neuroblastomas. Report From the SIOPEN Biology Group on the LNESG Trials and a COG Validation Group

For localized, resectable neuroblastoma without MYCN amplification, surgery only is recommended even if incomplete. However, it is not known whether the genomic background of these tumors may influence outcome.

How well do image-defined risk factors (IDRFs) predict surgical outcomes and survival in patients with neuroblastoma? A systematic review and meta-analysis

INTRODUCTION

Since their introduction to the International Neuroblastoma Risk Group (INRG) staging system in 2009, the role of Image-Defined Risk Factors (IDRFs) in predicting outcomes has been studied in heterogeneous populations with varying results. We conducted a systematic review and meta-analysis in order to determine quantitative measures of precisely how well pre-treatment IDRFs predict surgical outcomes and survival.

METHODS

A systematic review was performed for studies between January 1990 and July 2019 that compared surgical outcomes and/or survival in pediatric neuroblastoma patients with one or more IDRFs to patients without IDRFs. Summary risk ratios (RR) and hazard ratios (HR) were calculated using a random-effects model.

RESULTS

19 retrospective cohort studies were included, representing data from 1132 patients. The risk ratio (RR) of incomplete surgical resection in IDRF-positive patients compared to IDRF-negative patients was 2.45 (95% CI 1.51-3.97). The RR of surgical complications was 2.30 (95% CI 1.46-3.61). The hazard ratio (HR) for 5-year EFS was 2.08 (95% CI 2.93-4.13) while the 5-year HR for OS was 2.44 (95% CI 1.46-4.08).

CONCLUSION

IDRF-positive neuroblastoma patients have a higher risk of incomplete surgical resection, surgical complications, and 5-year mortality and/or relapse. Our results affirm that IDRFs remain a useful prognostic tool for neuroblastoma patients both for short and long-term outcomes.

LEVEL OF EVIDENCE

II.

Effects of preoperative chemotherapy on neuroblastoma with MYCN amplification: a surgeon’s perspective

Background

Preoperative chemotherapy plays an important role in the surgical management of unresectable neuroblastoma. Its response to chemotherapy has been variable due to the tumor’s heterogeneity. We aimed to evaluate the effects of preoperative chemotherapy on MYCN-amplified (MYCNA) neuroblastoma that would impact on surgical resection.

Methods

Patients with MYCNA neuroblastoma who received preoperative chemotherapy followed by surgical resection performed at our center were included. The tools of response evaluated included tumor volume reduction (TVR), reduction in image-defined risk factors (IDRFs), percentage tumor necrosis (Nec), and surgical complications.

Results

Among 62 patients evaluated, mean age was 3.0 (range, 0.9–11.8) years, and primary tumors were distributed in the abdomen (n=59), pelvis (n=2), and thorax (n=1). The patients were in stages L2 (n=14) and M (n=48). Surgery was performed after median of 4 (range, 2–10) cycles of chemotherapy. On completion of preoperative chemotherapy, 41 (66.1%) patients had TVR >65%, 24 (42.9%) responded with reduced IDRFs, 47 (75.8%) tumors had Nec >50%, and 27 patients suffered 31 surgical complications. Majority (83.9%) continued to have IDRFs at surgery. IDRFs commonly encountered were encasement of renal pedicles (n=50), superior mesenteric artery (n=46), celiac axis (n=45), and aorta/vena cava (n=44), and most remained refractory to resolution. Patients with TVR >65% were associated with Nec >50% (87.5% vs 54.5%, p=0.004) and reduced IDRFs (46.3% vs 19%, p=0.035), but not with the incidence of surgical complications.

Conclusions

Majority of MYCNA neuroblastomas were highly chemosensitive as they experienced high TVR, reduced IDRFs, and high Nec, and hence created favorable conditions for surgical resection. Poor responders and persistent IDRFs that were commonly refractory to preoperative chemotherapy remained a surgical challenge.

PRIMAGE project: predictive in silico multiscale analytics to support childhood cancer personalised evaluation empowered by imaging biomarkers

PRIMAGE is one of the largest and more ambitious research projects dealing with medical imaging, artificial intelligence and cancer treatment in children. It is a 4-year European Commission-financed project that has 16 European partners in the consortium, including the European Society for Paediatric Oncology, two imaging biobanks, and three prominent European paediatric oncology units. The project is constructed as an observational in silico study involving high-quality anonymised datasets (imaging, clinical, molecular, and genetics) for the training and validation of machine learning and multiscale algorithms. The open cloud-based platform will offer precise clinical assistance for phenotyping (diagnosis), treatment allocation (prediction), and patient endpoints (prognosis), based on the use of imaging biomarkers, tumour growth simulation, advanced visualisation of confidence scores, and machine-learning approaches. The decision support prototype will be constructed and validated on two paediatric cancers: neuroblastoma and diffuse intrinsic pontine glioma. External validation will be performed on data recruited from independent collaborative centres. Final results will be available for the scientific community at the end of the project, and ready for translation to other malignant solid tumours.

Association of image-defined risk factors, tumor resectability, and prognosis in children with localized neuroblastoma

BACKGROUND

Although localized neuroblastoma has a good prognosis, some cases have undergone treatment failure or recurrence. Apart from biologic features such as MYCN status, we wondered whether some characteristics of growing tumors are prognostic, such as a well-encapsulated mass without infiltration of vital organs. We analyzed the diagnostic utility of image-defined risk factors (IDRFs) to predict successful treatment and prognosis. The overall goal was to achieve maximum cure rates for patients with localized neuroblastoma through a better understanding of clinical characteristics.

METHODS

We retrospectively reviewed the images of patients with localized neuroblastoma who were enrolled between June 1998 and December 2012 at a single institution in Shanghai, China. Unequivocal categorization regarding IDRFs was available in 67 patients. IDRF was assessed at diagnosis and after four cycles of neoadjuvant chemotherapy, on average. The median follow-up period was 84 months (range: 48-132 months) after diagnosis.

RESULTS

MRI and CT indicated a total of 177 IDRFs in these 67 patients. Logistic regression analysis revealed a highly significant negative correlation between the numbers of IDRFs and the possibility of complete removal of neuroblastoma. Intraspinal extension of the tumor, compression of the trachea, and encasement of the main artery in localized neuroblastoma were predictors for incomplete tumor resection. According to univariate analysis, ≥ 4 IDRFs and intraspinal extension of the tumor were significant indicators of poor prognosis.

CONCLUSIONS

The number of IDRFs was useful in predicting surgical outcome and event-free survival. The number of IDRFs should be considered in protocol planning, instead of IDRF presence or absence.

Vessel adherent growth represents a major challenge in the surgical resection of neuroblastoma and Is associated with adverse outcome

PURPOSE

Neuroblastoma (NB) is the most common extracranial, solid tumor in childhood, with a peak incidence in children under 6 years of age. Due to its variable course of disease, which ranges from spontaneous regression to metastatic spread, NB still represents a significant therapeutic challenge. Strikingly, a certain number of NBs intraoperatively show vessel adhesion and/or infiltrative growth, which is often not visible in pre-operative imaging. We proposed the term unexpected vessel infiltration of NB (UVIN) to denote this phenomenon. UVIN represents a major surgical challenge.

METHODS

In this study, we determined frequency and clinical relevance of UVIN in a cohort of 100 NB-patients with subsequent correlation to several unfavorable characteristics of disease. RNA expression levels of MYCN and its co-regulated antisense transcript MYCNOS to identify markers was measured by PCR.

RESULTS

We found UVIN to be present in 34% of cases and significantly correlated with incomplete resection, MYCN amplification, complications, neoadjuvant therapy, tumor grade and MYCNOS expression levels. MYCN expression levels showed no significant results with UVIN.

CONCLUSION

Collectively, our data show that UVIN represents a frequent surgical problem associated with a poor outcome in NB patients. MYCN and MYCNOS seem to be no appropriate markers for UVIN.

TYPE OF STUDY

Prognosis study.

LEVEL OF EVIDENCE

Level III.

Surgical risk factors of retroperitoneal teratoma resection in children

BACKGROUND

Retroperitoneal teratoma is uncommon and carries considerable surgical risks. Some preoperative clinical and radiographic features could be predictive of surgical complication risk. We aimed to identify surgical risk factors that predicted perioperative complications.

METHODS

Childhood retroperitoneal teratoma cases operated on at Guangzhou Women and Children's Medical Center were retrospectively reviewed. Demographic features; clinical, laboratory, radiographic, and intraoperative findings; perioperative complications; and pathology results were assessed.

RESULTS

Between May 2000 and December 2017, 152 childhood retroperitoneal teratomas were resected from 102 female patients (median age 5.75 months). Sixty-three patients (41%) experienced perioperative complications (79 intraoperative and 5 postoperative), including kidney excision (4 patients) and adrenal gland excision (1 patient). Among 113 patients with preoperative computed tomography/magnetic resonance images, 112 (99%), 111 (98%), and 113 (100%) demonstrated artery, vein, and organ distortion, respectively, and 28 (25%) had vessels encased by tumors. Patients with perioperative complications had more veins and organs distorted by tumors. In multivariate analysis, the numbers of vessels encased and organs distorted by tumors were significantly associated with perioperative complications (odds ratio = 1.45 and 1.69, 95% confidence interval: 1.00-2.10 and 1.19-2.41, respectively).

CONCLUSIONS

Retroperitoneal teratoma resection has a high perioperative complication rate. Teratomas encompassing the vasculature and distorting organs were associated with increased surgical risk. Additional studies aiming to better define the surgical approach to retroperitoneal teratoma are warranted.

LEVELS OF EVIDENCE

III.

Association between image-defined risk factors and neuroblastoma outcomes

BACKGROUND

The current neuroblastoma (NBL) staging system employs image-defined risk factors (IDRFs) to assess numerous anatomic features, but the impact of IDRFs on surgical and oncologic outcomes is unclear.

METHODS

The Vanderbilt Cancer Registry identified children treated for NBL from 2002 to 2017. Tumor volume (TV) and IDRFs were measured radiographically at diagnosis and before resection. Perioperative and oncologic outcomes were evaluated.

RESULTS

At diagnosis of 106 NBL, 61% were IDRF positive. MYCN-amplified and undifferentiated NBL had more IDRFs than nonamplified and more differentiated tumors (p = 0.001 and p = 0.01). Of 86 NBLs resected, 43% were IDRF positive, which associated with higher stage, risk, and TV (each p < 0.001). The presence of IDRF at resection was also associated with increased blood loss (p < 0.001), longer operating times (p < 0.001), greater incidence of intraoperative complications (p = 0.03), more frequent ICU admissions postoperatively (p < 0.001), and longer hospital stays (p < 0.001). IDRF negative and positive tumors did not have significantly different rates of gross total resection (p = 0.2). Five-year relapse-free and overall survival was similar for IDRF negative and positive NBL (p = 0.9 and p = 0.8).

CONCLUSIONS

IDRFs at diagnosis were associated with larger, less differentiated, advanced stage, and higher risk NBL and at resection with increased operative difficulty and perioperative morbidity. However, the frequency of gross total resection and patient survival after resection were not associated with the presence of IDRFs.

TYPE OF STUDY

Retrospective cohort study.

LEVEL OF EVIDENCE

Level III.

The Evolution of Risk Classification for Neuroblastoma

Neuroblastoma is a tumor with great clinical heterogeneity. Patients in North America are risk-stratified using a number of features including age at diagnosis, disease stage, tumor histology, MYCN status (amplified versus nonamplified), and tumor cell ploidy. In this paper, we review the evidence for utilizing these features in the risk classification of neuroblastic tumors. Additionally, we review the clinical and biologic criteria used by various cooperative groups to define low, intermediate, and high-risk disease populations in clinical trials, highlighting the differences in risk classification internationally. Finally, we discuss the development of the International Neuroblastoma Risk Group classification system, designed to begin worldwide standardization of neuroblastoma pretreatment risk classification and allow comparison of clinical trials conducted through different cooperative groups.

Advances in the Surgical Treatment of Neuroblastoma

OBJECTIVE

This study was to review the efficacy of surgical resections in different clinical situations for a better understanding of the meaning of surgery in the treatment of neuroblastoma (NB).

DATA SOURCES

The online database ScienceDirect (201-2018) was utilized. The search was conducted using the keywords "neuroblastoma," "neuroblastoma resection," "neuroblastoma surgery," and "high-risk neuroblastoma."

STUDY SELECTION

We retrospectively analyzed of patients who underwent surgical resections in different clinical situations. The article included findings from selected relevant randomized controlled trials, systematic reviews, and meta-analyses or good-quality observational studies. Abstracts only, letters, and editorial notes were excluded. Full-text articles and abstracts were extracted and reviewed to identify key articles discussing surgery management of NB, which were then selected for critical analysis.

RESULTS

A total of 7800 English language articles were found containing references to NB (201-2018). The 163 articles were searched which were related to the surgical treatment of NB (201-2018). Through the analysis of these important articles, we found that the treatments of NB at low- and intermediate-risk groups were basically the same. High-risk patients remained controversial.

CONCLUSIONS

NB prognosis varies tremendously based on the stage and biologic features of the tumor. After reviewing the relevant literature, patients with low-risk disease are often managed with surgical resection or observation alone with tumors likely to spontaneously regress that are not causing symptoms. Intermediate patients are treated with chemotherapy with the number of cycles depending on their response as well as surgical resection of the primary tumor. High-risk patients remain controversial. Multidisciplinary intensive treatment is essential, especially for patients who received subtotal tumor resection. Minimally invasive surgery for the treatment of NBs without image-defined risk factors in low- to high-risk patients is safe and feasible and does not compromise the treatment outcome. We conclude that ≥90% resection of the primary tumor is both feasible and safe in most patients with high-risk NB. New targeted therapies are crucial to improve survival.

Characteristics and management of ganglioneuroma and ganglioneuroblastoma-intermixed in children and adolescents

BACKGROUND

Ganglioneuromas (GNs) usually demonstrate favorable histological and clinical features. Surgery is often performed due to clinical symptoms and/or theoretical concerns that GN may transform into neuroblastoma (NB); however, several studies have identified significant GN-surgical morbidities.

OBJECTIVES

We compared the natural history, biological and clinical features of GN and ganglioneuroblastoma-intermixed (GNB-I) managed by surgery or observation to inform management and surveillance.

PROCEDURES

This retrospective study includes patients (n = 67) with histological diagnosis of GN (50/67) and GNB-I (17/67) at the Hospital for Sick Children between 1990 and 2014. Clinical, pathological features, tumor dimensions, and management were recorded.

RESULTS

Median age and maximal tumor diameter were 6 years (1.3-17.8) and 6.3 cm (1.4-16.9), respectively. Of the 67 patients, 46 (69%) had upfront surgery and 21 (31%) were observed. Of the 21 observed patients 4 later underwent resection. There were post-operative complications in 15 of the 50 (30%) surgical patients. The presence of imaging-defined risk factors correlated with complications (P = 0.005). Observed patients were older (median 8.4 vs. 5.3 years) and diagnosed more recently. Median growth was 0.3 cm/year and 6 of 21 had progressive disease (PD). At median follow-up of 2.2 years (0.2-14.3), all patients were alive and for those with evaluable imaging there were 27 complete and 10 partial responses, 19 stable and 6 PD. Pathology classification changed at resection for three cases, but no GN was reclassified to NB.

CONCLUSIONS

GN and GNB-I have a slow growth rate and resection can be associated with significant morbidity. Watch and wait approaches should be considered for some GN and GNB-I.

Prognostic impact of postoperative 123I-metaiodobenzylguanidine scintigraphy: added value of SPECT/CT and semiquantification of the uptake at the surgical site

BACKGROUND

The aim of this study was to assess the prognostic value of postoperative 123I-MIBG scintigraphy, including systematic SPECT/CT and semiquantification of the uptake at the surgical site, in a prospective series of NB patients.

METHODS

Patients operated for neuroblastoma and who had benefited from postoperative 123I-MIBG scintigraphy were prospectively and consecutively included. Completeness of surgery was assessed on operative report. One month postoperative 123I-MIBG scintigraphy included planar acquisition and SPECT/CT. Semi-quantification of the 123I-MIBG SPECT/CT uptake at the surgical site was performed and ratios to reference (liver and mediastinum) areas were calculated.

RESULTS

Thirty patients were included between August 2012 and July 2015. Median follow-up was 36 months (range 10-98). Surgery was considered as complete in 23 patients and incomplete in 7 patients. Eight patients (26.7%) presented progressive disease (1 progression and 7 recurrences). Seven patients died (23.3%), all from NB. Six (20%) patients had positive 123I-MIBG scintigraphy (3 on planar acquisitions and 6 on SPECT/CT) and 24 patients had negative 123I-MIBG scintigraphy. Five of the 6 patients (83%) with positive 123I-MIBG scintigraphy presented progressive disease. Ratio of the uptake at the surgical site to mediastinum was strongly and independently correlated with disease-free interval and overall survival (P=0.02 and 0.01 respectively). The amplified MYCN status was also confirmed as correlated with poorer outcomes.

CONCLUSIONS

Postoperative 123I-MIBG scintigraphy including SPECT/CT and semiquantification of the uptake at the surgical site appeared to be a valuable prognostic tool in neuroblastoma.

Radiogenomics of neuroblastomas: Relationships between imaging phenotypes, tumor genomic profile and survival

Purpose

This study investigated relationships between neuroblastomas (NBs) imaging phenotypes, tumor genomic profile and patient outcome.

Patients and methods

This IRB-approved retrospective observational study included 133 NB patients (73 M, 60 F; median age 15 months, range 0–151) treated in a single institution between 1998 and 2012. A consensus review of imaging (CT-scan, MRI) categorized tumors according to both the primarily involved compartment (i.e., neck, chest, abdomen or pelvis) and the sympathetic anatomical structure the tumors rose from (i.e., cervical, paravertebral or periarterial chains, or adrenal gland). Tumor shape, volume and image-defined surgical risk factors (IDRFs) at diagnosis were recorded. Genomic profiles were assessed using array-based comparative genomic hybridization and divided into three groups: “numerical-only chromosome alterations” (NCA), “segmental chromosome alterations” (SCA) and “MYCN amplification” (MNA). Statistical analyses included Kruskal–Wallis, Chi² and Fisher’s exact tests and the Kaplan-Meier method with log-rank tests and Cox model for univariate and multivariate survival analyses.

Results

A significant association between the sympathetic structure origin of tumors and genomic profiles was demonstrated. NBs arising from cervical sympathetic chains were all NCA. Paravertebral NBs were NCA or SCA in 75% and 25%, respectively and none were MNA. Periarterial NBs were NCA, SCA or MNA in 33%, 56% and 11%, respectively. Adrenal NBs were NCA, SCA or MNA in 16%, 36% and 48%, respectively. Among MNA NBs, 92% originated from the adrenal gland. The sympathetic anatomical classification was significantly better correlated to overall survival than the compartmental classification (P < .0003). The tumor volume of MNA NBs was significantly higher than NCA or SCA NBs (P < .0001). Patients with initial volume less than 160 mL had significantly better overall survival (P < .009). A “single mass” pattern was significantly more frequent in NCA NBs (P = .0003). The number of IDRFs was significantly higher in MNA NBs (P < .0001).

Conclusion

Imaging phenotypes of neuroblastomas, including tumor origin along the sympathetic system, correlate with tumor genomic profile and patient outcome.

DO THE RADIOLOGICAL CRITERIA WITH THE USE OF RISK FACTORS IMPACT THE FORECASTING OF ABDOMINAL NEUROBLASTIC TUMOR RESECTION IN CHILDREN?

BACKGROUND

The treatment of neuroblastoma is dependent on exquisite staging; is performed postoperatively and is dependent on the surgeon's expertise. The use of risk factors through imaging on diagnosis appears as predictive of resectability, complications and homogeneity in staging.

AIM

To evaluate the traditional resectability criteria with the risk factors for resectability, through the radiological images, in two moments: on diagnosis and in pre-surgical phase. Were analyzed the resectability, surgical complications and relapse rate.

METHODS

Retrospective study of 27 children with abdominal and pelvic neuroblastoma stage 3 and 4, with tomography and/or resonance on the diagnosis and pre-surgical, identifying the presence of risk factors.

RESULTS

The mean age of the children was 2.5 years at diagnosis, where 55.6% were older than 18 months, 51.9% were girls and 66.7% were in stage 4. There was concordance on resectability of the tumor by both methods (INSS and IDRFs) at both moments of the evaluation, at diagnosis (p=0.007) and post-chemotherapy (p=0.019); In this way, all resectable patients by IDRFs in the post-chemotherapy had complete resection, and the unresectable ones, 87.5% incomplete. There was remission in 77.8%, 18.5% relapsed and 33.3% died.

CONCLUSIONS

Resectability was similar in both methods at both pre-surgical and preoperative chemotherapy; preoperative chemotherapy increased resectability and decreased number of risk factors, where the presence of at least one IDRF was associated with incomplete resections and surgical complications; relapses were irrelevant.

Overview and recent advances in the treatment of neuroblastoma

INTRODUCTION

Children with neuroblastoma have widely divergent outcomes, ranging from cure in >90% of patients with low risk disease to <50% for those with high risk disease. Recent research has shed light on the biology of neuroblastoma, allowing for more accurate risk stratification and treatment reduction in many cases, although newer treatment strategies for children with high-risk and relapsed neuroblastoma are needed to improve outcomes. Areas covered: Neuroblastoma epidemiology, diagnosis, risk stratification, and recent advances in treatment of both newly diagnosed and relapsed neuroblastoma. Expert commentary: The identification of newer tumor targets and of novel cell-mediated immunotherapy agents may lead to novel therapeutic approaches, and clinical trials for regimens designed to target individual genetic aberrations in tumors are underway. A combination of therapeutic modalities will likely be required to improve survival and cure rates for patients with high-risk neuroblastoma.

Laparoscopic resection of neuroblastomas in low- to high-risk patients without image-defined risk factors is safe and feasible

BACKGROUND

Several studies have reported that minimally invasive surgery (MIS) might be considered for resecting neuroblastomas without image-defined risk factors (IDRFs); however, there are no studies comparing the outcomes of laparotomy and laparoscopy in IDRF-negative patients. Thus, we investigated the feasibility of laparoscopic surgery and compared the two abovementioned approaches.

METHODS

To compare the effects of laparotomy with those of laparoscopy in patients with neuroblastomas without IDRFs, the following items were retrospectively compared: largest tumor dimension, volume of blood loss, time required to initiate postoperative feeding, locoregional recurrence rate, survival, etc.

RESULTS

Nine patients without IDRFs (three at low-to-medium risk and six at high risk) underwent laparotomy, and seven patients without IDRFs (two at low-to-medium risk and five at high risk) underwent laparoscopy. Median duration of surgery was 221 (130-304) and 172 (122-253) min in the laparotomy and laparoscopy groups, respectively, showing no significant difference. Median postoperative time required for resuming meal consumption was significantly longer in the laparotomy (4 days; 2-5) group than that in the laparoscopy group (3 days; 2-3; p = 0.023). Median blood loss was significantly higher in the laparotomy group (5 ml/Kg;2.6-16) than that in the laparoscopy group (2.1 ml/Kg;0.1-4.0; P = 0.037). Median follow-up period was 81 (52-94) and 21 (17-28) months, locoregional recurrence rates were 22 and 0% at 1 year, 1-year progression-free survival rates were 78 and 100%, and overall survival rates were 67 and 100% in the laparotomy and laparoscopy groups, respectively, with no significant differences.

CONCLUSIONS

MIS for the treatment of neuroblastomas without IDRFs in low- to high-risk patients is safe and feasible and does not compromise the treatment outcome.

What is new in pediatric surgical oncology?

PURPOSE OF REVIEW

As pediatric oncology has become more complex, designing and maintaining pediatric surgical protocols require greater expertise. The primary purpose of this review is to summarize the changes in protocols and new study findings, which have changed surgical practice for children with solid tumors.

RECENT FINDINGS

The most common solid tumors treated by surgery are reviewed. There are new methods of surgical techniques such as the use of sentinel lymph node techniques for the assessment of lymph nodes in pediatric sarcoma. New studies showing excellent outcomes for the nonoperative treatment for young patients with neuroblastoma are discussed. Surgical quality with the prevention of tumor rupture and the assessment of lymph nodes is essential for good outcomes in patients with Wilm's tumor. The international collaborations within germ cell and liver tumors have provided excellent new study regimens and welcomed a new era of studies that are robust and have the power to change the outcomes for these rare tumors.

SUMMARY

Surgical practice is evolving with the molecular advances in pediatric oncology. Technical advances and quality improvement endeavors to ensure protocol adherence are essential. International partnerships have allowed for greater advances particularly for rare tumors and improve overall surgical outcomes.

Neuroblastoma (Peripheral neuroblastic tumours)

Peripheral neuroblastic tumours (PNTs), a family of tumours arising in the embryonal remnants of the sympathetic nervous system, account for 7-10% of all tumours in children. In two-thirds of cases, PNTs originate in the adrenal glands or the retroperitoneal ganglia. At least one third present metastases at onset, with bone and bone marrow being the most frequent metastatic sites. Disease extension, MYCN oncogene status and age are the most relevant prognostic factors, and their influence on outcome have been considered in the design of the recent treatment protocols. Consequently, the probability of cure has increased significantly in the last two decades. In children with localised operable disease, surgical resection alone is usually a sufficient treatment, with 3-year event-free survival (EFS) being greater than 85%. For locally advanced disease, primary chemotherapy followed by surgery and/or radiotherapy yields an EFS of around 75%. The greatest problem is posed by children with metastatic disease or amplified MYCN gene, who continue to do badly despite intensive treatments. Ongoing trials are exploring the efficacy of new drugs and novel immunological approaches in order to save a greater number of these patients.

Magnetic resonance imaging of the mediastinum, chest wall and pleura in children

The acceptance of applications for the use of chest MRI in children has been somewhat slow and selective. The use of MRI to image chest wall lesions is likely the most common and widely used indication, aside from the widespread and somewhat sophisticated use of MRI in imaging the cardiovascular structures of the chest. In this respect, fairly standard variations of T1-W, T2-W and contrast-enhanced imaging can be used, similar to the sequences used for musculoskeletal lesions elsewhere in the body. Imaging of the anterior mediastinal masses should be performed in conjunction with a detailed pre-test clinical examination to determine potential cardiovascular compromise. MRI in the setting of middle mediastinal adenopathy, congenital mediastinal cysts or posterior mediastinal masses, however, has been shown to be more effective and more comprehensive than multidetector CT. Although sonographic imaging is the initial modality of choice for pleural abnormalities, MR imaging is extremely effective and clinically useful in the setting of a potentially ambiguous sonographic examination. Faster imaging protocols are likely to increase the acceptance of MRI to replace multidetector CT for many pediatric chest lesions.

Validity of image-defined risk factors in localized neuroblastoma: A report from two centers in Western Japan

BACKGROUND

Japanese Neuroblastoma Study Group (JNBSG) has been employing image-defined risk factors (IDRFs) since 2010. However, the report from INRG in 2011 supplemented description stating that isolated contact is considered to be IDRF-positive only in renal vessels. The aim of this study was to evaluate the validity of IDRFs by comparing the previous (PG) and new guidelines (NG).

METHODS

IDRFs of patients with localized neuroblastoma treated at two centers in Western Japan from 2002 to 2013 were retrospectively reviewed by radiologists.

RESULTS

47 neuroblastomas (abdomen 38, pelvis 2, mediastinum 7) were evaluated. For abdominal neuroblastomas, IDRFs were present in 15/38 (39.5%) using PG and in 31/38 (81.6%) using NG. Moreover, the IDRF-positive rate increased from 26.7% (4/15) to 80.0% (12/15) in 15 cases diagnosed during mass screening. Of the IDRF-positive cases, complete primary resection was achieved in 2/15 (13.3%) using PG and 17/31 patients (54.8%) using NG. There were two major surgical renal complications in the IDRF-positive cases based on the use of either guidelines, and the specificity decreased from 64% to 19%.

CONCLUSIONS

According to NG, the IDRF-positive rate increased, and the resection rate decreased. NG may overestimate surgical risks, leading to unnecessary chemotherapy and a prolonged hospital stay.