Neuroblastoma in children: Update on clinicopathologic and genetic prognostic factors

Neuroblastoma is the most common extracranial solid tumor in childhood accounting for 8–10% of all childhood malignancies. The tumor is characterized by a spectrum of histopathologic features and a heterogeneous clinical phenotype. Modern multimodality therapy results in variable clinical response ranging from cure in localized tumors to limited response in aggressive metastatic disease. Accurate clinical staging and risk assessment based on clinical, surgical, biologic and pathologic criteria are of pivotal importance in assigning prognosis and planning effective treatment approaches. Numerous studies have analyzed the presence of several clinicopathologic and biologic factors in association with the patient's prognosis and outcome. Although patient's age, tumor stage, histopathologic classification, and MYCN amplification are the most commonly validated prognostic markers, several new gene mutations have been identified in sporadic and familial neuroblastoma cases that show association with an adverse outcome. Novel molecular studies have also added data on chromosomal segmental aberrations in MYCN nonamplified tumors. In this review, we provide an updated summary of the clinical, serologic and genetic prognostic indicators in neuroblastoma including classic factors that have consistently played a role in risk stratification of patients as well as newly discovered biomarkers that may show a potential significance in patients' management.     

Surgical management of neuroblastoma

Neuroblastoma treatment remains challenging but has been advanced by the establishment of clinical and biological variables that determine prognostic risk. Risk-based therapy currently is the hallmark of neuroblastoma treatment. Initially, stage and age were the prime determinants of survival used in clinical practice. The Shimada histopathologic classification added to the former 2 and biochemical markers like the serum ferritin, lactic dehydrogenase, and neuron-specific enolase also provided information regarding prognosis. The current era of neuroblastoma therapy has been influenced heavily by advances in molecular biology, most notably the identification of the MYCN oncogene and the application of recombinant DNA methods to identification of chromosomal deletions. Current risk assessment includes age, stage, histopathology, and biochemical markers but also analyses performed on DNA extracted from fresh tumors. This places the onus of obtaining an adequate quantity and quality of fresh neuroblastoma tissue directly on the pediatric surgeon who performs the initial biopsy.     

Neuroblastoma: biology, prognosis, and treatment

Neuroblastoma, a neoplasm of the sympathetic nervous system, is the second most common extracranial malignant tumor of childhood and the most common solid tumor of infancy. Neuroblastoma is a heterogeneous malignancy with prognosis ranging from near uniform survival to high risk for fatal demise. Neuroblastoma serves as a paradigm for the prognostic utility of biologic and clinical data and the potential to tailor therapy for patient cohorts at low, intermediate, and high risk for recurrence. This article summarizes our understanding of neuroblastoma biology and prognostic features and discusses their impact on current and proposed risk stratification schemas, risk-based therapeutic approaches, and the development of novel therapies for patients at high risk for failure.     

Neuroblastoma

Neuroblastoma is a heterogeneous disease; tumors can spontaneously regress or mature, or display an aggressive, therapy-resistant phenotype. Increasing evidence indicates that the biological and molecular features of neuroblastoma significantly influence and are highly predictive of clinical behavior. Because of this, neuroblastoma has served as a paradigm for biological risk assessment and treatment assignment. Most current clinical studies of neuroblastoma base therapy and its intensity on a risk stratification that takes into account both clinical and biological variables predictive of relapse. For example, surgery alone offers definitive therapy with excellent outcome for patients with low-risk disease, whereas patients at high risk for disease relapse are treated with intensive multimodality therapy. In this review recent advances in the understanding of the molecular genetic events involved in neuroblastoma pathogenesis are discussed, and how they are impacting the current risk stratification and providing potential targets for new therapeutic approaches for children with neuroblastoma. In addition, the results of significant recent clinical trials for the treatment of neuroblastoma are reviewed.     

Radically different treatment recommendations for newly diagnosed neuroblastoma: pitfalls in assessment of risk

Neuroblastoma risk stratification is based on stage, age, and biology and prescribes surgery for low-risk disease, moderate-dose chemotherapy for intermediate-risk disease, and maximal therapy (including myeloablative treatment with stem cell transplantation) for high-risk disease. Four cases are described that depict pitfalls in risk assessment with potentially far-reaching consequences. This report focuses on a subset of four patients referred for second opinions. Stage was defined by the International Neuroblastoma Staging System. The first recommendations were for maximal therapy, but second opinions were radically different (ie, surgery alone). Ages at diagnosis were 15 to 25 months. Shimada histopathology was unfavorable in three of the four patients, but chromosomal, serum, and urine prognostic markers were favorable. All four patients did well without cytotoxic therapy (follow-up: 2 years 10 months plus to 4 years 8 months plus). Patient 1 had abdominal and upper thoracic/supraclavicular masses (stage 4); the former was resected and the latter spontaneously regressed. Patient 2 had retroperitoneal disease, without bone marrow involvement, but imaging studies showed lesions in vertebral bodies. Biopsies of the latter showed no neuroblastoma and the primary tumor (with regional lymph nodes) was resected, changing stage from 4 to 2B. Patient 3 had a retroperitoneal mass but no distant disease. Though initially deemed to be unresectable, the abdominal tumor was excised, changing the classification from high risk (stage 3 with unfavorable histopathology) to low risk (stage 1). Patient 4 had a pelvic mass, with unfavorable histopathology, and bilateral inguinal lymph node involvement (stage 3); all soft tissue disease was resected. The absence of cortical bone and extensive bone marrow metastatic involvement in a young neuroblastoma patient should cause a shift in attention to biologic prognostic markers. Some patients classified as having high-risk neuroblastoma might actually do well with no cytotoxic therapy.     

New aspects of neuroblastoma treatment: ASPHO 2011 symposium review

Neuroblastoma is the most common extracranial solid tumor of childhood, and the outcomes for children with high-risk and relapsed disease remain poor. However, new international strategies for risk stratification and for treatment based on novel tumor targets and including immunotherapy are being employed in attempts to improve the outcomes of children with neuroblastoma. A new international neuroblastoma risk classification system has been developed which is being incorporated into cooperative group clinical trials in North America, Japan, and Europe, resulting in standardized approaches for the initial evaluation and treatment stratification of neuroblastoma patients. Furthermore, novel treatment regimens are being developed based on improved understanding of neuroblastoma biology and on the recruitment of the immune system to specifically target neuroblastoma tumors. These approaches will lead to new therapeutic strategies that likely will improve the outcomes for children with neuroblastoma worldwide.     

The role of genetic and epigenetic alterations in neuroblastoma disease pathogenesis

Neuroblastoma is a highly heterogeneous tumor accounting for 15 % of all pediatric cancer deaths. Clinical behavior ranges from the spontaneous regression of localized, asymptomatic tumors, as well as metastasized tumors in infants, to rapid progression and resistance to therapy. Genomic amplification of the MYCN oncogene has been used to predict outcome in neuroblastoma for over 30 years, however, recent methodological advances including miRNA and mRNA profiling, comparative genomic hybridization (array-CGH), and whole-genome sequencing have enabled the detailed analysis of the neuroblastoma genome, leading to the identification of new prognostic markers and better patient stratification. In this review, we will describe the main genetic factors responsible for these diverse clinical phenotypes in neuroblastoma, the chronology of their discovery, and the impact on patient prognosis.     

An update on neuroblastoma

Neuroblastoma is an embryonal tumour of the sympathetic nervous system. Presentation and disease course can vary widely, ranging from tumours that display spontaneous regression to those that follow an unrelenting, progressive course despite treatment, with an inevitably fatal outcome. Prognosis depends upon age at diagnosis, extent of disease and tumour biology. Most tumours develop within the retroperitoneum; more than one-half of patients have widespread metastatic disease at diagnosis. Overexpression of oncogenes, gain or loss of genetic material, inactivation of tumour suppressor genes, and alterations in the expression of genes affecting survival, differentiation and apoptosis of neuroblastoma cells are thought to be important in disease behaviour. Staging and risk-based therapy governed by risk stratification according to the International Neuroblastoma Risk Group (INRG) classification system are discussed, along with emerging novel therapies and treatment strategies.     

Neuroblastoma: a master of disguise and a challenge to cure

Neuroblastoma is one of the commonest childhood cancers and typically affects very young children. It is characterized by a very broad spectrum of clinical presentation and outcome, driven by the biology of the tumour. This ranges from ‘low risk’ tumours, most commonly found in infants, which may spontaneously regress and have an excellent prognosis with minimal or no treatment, to ‘high risk’ disease, which carries a poor prognosis despite intensive multi-modal treatment. Although particular presentations may be associated with favourable or unfavourable outcome, the clinical features may mask the underlying biology of the tumour and a full assessment of the clinical and biological features is required to determine appropriate treatment. The International Neuroblastoma Risk Group classification, based on the age of the patient and the stage, grade and genetics of the tumour, is used to stratify treatment according to risk factors. This review provides an overview of current neuroblastoma management, focusing on how classification is applied in practice, and how this is used to determine individual patient treatment. The challenges that remain in treating patients with high-risk disease are discussed.     

Prognosis of neuroblastoma in childhood. Methods of assessment and clinical use]

Neuroblastoma and its benign counterpart, ganglioneuroma, are pediatric neuroblastic tumors arising in the sympathetic nervous system from neural-crest cells. Neuroblastoma, the most common extra-cranial solid tumour during childhood, is unique for its broad spectrum of clinical virulence from spontaneous remission to rapid and fatal progression despite intensive multimodality therapy. To a large extent, outcome could be predicted by the stage of disease and the age at diagnosis. However, a number of molecular events in neuroblastoma tumors, accounting for the variability of outcome and response to therapy, have been identified over the past decades. Among these, MYCN amplification is the most relevant prognostic factor and was the first genetic marker, in paediatric oncology, to be included in clinical strategies as a guide for therapeutic decision. This has allowed the most suitable intensity of therapy to be delivered according to a risk-stratified strategy, from observation to megadose chemotherapy with stem cell transplantation. Recent advances in understanding the biology and genetics of neuroblastoma will ultimately allow to select poor-risk patients for appropriate future biologically based therapies.     

Congenital neuroblastoma arising in the deltoid muscle

Neuroblastoma almost always arises in association with sympathetic neural crest tissues that flank the spinal axis, including the paravertebral sympathetic ganglia of the neck, mediastinum, retroperitoneum, and pelvis, or in the adrenal glands. Neuroblastoma in the newborn period, which can present as localized or metastatic disease, often resolves spontaneously and requires little or no therapy. The authors describe a 5-week-old infant with an isolated primary neuroblastoma arising in the deltoid muscle. Histologic and biologic characteristics were consistent with a favorable-prognosis stage 1 neuroblastoma. Following a complete local excision, the child remains in complete remission 3 years from diagnosis.     

Neuroblastoma

The neuroblastic tumours originate from primordial neural crest cells that normally develop into sympathetic nervous system, including the adrenal medulla. Neuroblastoma is the most intriguing pediatric neoplasm displaying diverse clinical and biologic characteristics and natural history¹. It has thre highest rate of spontaneous regression of all human cancers, yet exhibits extremely malignant behaviour in older children with regional and disseminated disease. In the last 30 years, only a nominal improvement has occurred in the outlook of older children with metastatic disease at diagnosis. Tremendous gains in understanding of the biology of neuroblastoma in recent years have led to development of risk-related therapy based on age, stage and biological characteristics of neuroblastoma.     

Fetal and neonatal neuroblastoma: retrospective review of 271 cases

Neuroblastoma is the foremost malignant neoplasm of the fetus and neonate. The tumor is unique because of its distinctive biologic behavior and many different clinical manifestations. The purpose of this review is to focus on the fetus and neonate to determine the various ways perinatal neuroblastomas differ clinically and morphologically and in their treatment from those found in the older child to show that some forms of the tumor have a better outcome than others. The report attempts to evaluate the influence of site, histology, stage, biologic markers, and treatment on survival.     

Risk estimation of neuroblastoma patients using molecular markers

The pediatric tumor neuroblastoma is a heterogeneous disease: Patients' clinical courses can range from spontaneous regression to fatal progression of the disease. Accordingly, treatment protocols vary from "wait and see" approaches to intensive multimodal therapies. Accurate risk estimation of the patients is therefore mandatory to choose the most adequate therapy. Current trials stratify by a limited number of clinical variables, such as stage of the disease and age of the patient at diagnosis, as well as molecular markers, such as amplification of the oncogene MYCN and loss of the short arm of chromosome 1. However, misclassifications of patients still occur, and thus, a precise prediction of the clinical courses remains a challenge of neuroblastoma research. In recent years, genomic alterations and gene expression profiles of this neoplasm have been characterized thoroughly. It has been shown that the diverse clinical phenotypes are reflected by both specific cytogenetic aberrations and distinct gene expression patterns. Moreover, a variety of DNA copy number changes and gene expression-based classifiers have been described that could predict the outcome of neuroblastoma patients more precisely than established prognostic variables. In this review, the recent advances in the detection and evaluation of molecular prognostic markers for neuroblastoma patients are summarized, and their current and potential contribution to risk stratification systems is discussed.     

Cystic Neuroblastoma: Emphasis on Gene Expression, Morphology, and Pathogenesis

Cystic neuroblastoma (CN) is an unusual variant of neuroblastoma characterized by a grossly visible cyst(s) and almost always distinctive microcysts on light microscopy. Rarely, CN will appear solid grossly, but microcystification will be present. We examined the clinical, pathologic, and biologic features of 17 cases of CN. The majority of CN had been detected by prenatal ultrasound. The tumors were favorable stage, stroma-poor, but with low or intermediate mitotic-karyorhectic indices and had favorable biologic markers reflected by aneuploidy and by an absence of N-myc amplification and chromosome 1p deletions. However, the high trk expression typically identified in good risk tumors was absent. Although the complete natural history of CN is not fully defined, our experience suggests that some tumors progress in size, whereas others may spontaneously regress or mature. The clinical outcome is excellent, as is expected in localized and stage 4S neuroblastoma in infancy. Received June 13, 1996; accepted June 19, 1997     

Staging systems for neuroblastoma: a look at the old and the new

Anatomic staging systems for neurobalstoma are important in determining tumor distribution, intensity of therapy required and patient prognosis. Classic staging has utilized two approaches: one defines the initial anatomic distribution of disease at diagnosis; the second includes considerations for degree of resectability of the primary tumor. Many currently used systems are generally incompatible and unable to distinguish patients in the intermediate prognastic groups. A new International Neuroblastoma Staging System (INSS) is proposed which combines components of initial distribution of disease as well as surgical resectability. Uniform evaluation of response to therapy is also part of the INSS. Biologic staging neuroblastoma may become important in the future and the INSS proposal allows enough flexibility to incorporate this into a more standardized classification system.     

Neuroblastoma: the case for screening infants in North America

Neuroblastoma is a disease in which easily measured tumor markers are excreted. It is curable when diagnosed in an early stage and at an early age, and it has a high incidence relative to other serious childhood diseases. Recent advances in screening infants for neuroblastoma by detection of urinary homovanillic acid and vanillylmandelic acid, the most useful markers of neuroblastoma, are described. Based on results from Japan's mass-screening program and on the authors' observations, it is estimated that mass screening for neuroblastoma could save 260 lives annually in the United States.     

基于支持向量机神经母细胞瘤血清蛋白质标记物的检测及临床应用

目的 寻找神经母细胞瘤特异血清蛋白标记物,构建初步诊断模型,并探讨其临床应用价值.方法 收集47例神经母细胞瘤患儿血清标本,30例其它恶性实体肿瘤患儿血清标本以及健康儿童血清标本10例;用ZUCI-Protein Chip Data Analyze System分析软件进行数据处理;经留一法交叉验证,分类器评价模型的预测效果.结果 构建3个模型并筛选出10个蛋白标记物,能够成功区分神经母细胞瘤和健康儿童蛋白质谱的差异,表达模型的敏感性为100%,特异性为100%,区分神经母细胞瘤术前和术后蛋白质潜差异表达模型的敏感性为100%,特异性为100%,区分神经母细胞瘤与其它小儿恶性实体肿瘤血清蛋白质指纹图谱模型的敏感性为88.89%.特异性为100%.结论 用SELDI-TOF-MS及生物信息学技术并结合支持向量机(SVM)初步建立的模型可作为神经母细胞瘤的另一种特异性强、敏感性高的辅助检查手段.     

血清蛋白质标记物在神经母细胞瘤中的诊断意义

目的 寻找特异的蛋白质标记物,探讨神经母细胞瘤血清蛋白质标记物的检测及初步诊断模型的构建和临床应用.方法 收集血清样本87例,其中47例为神经母细胞瘤患儿,30例为其它恶性实体肿瘤患儿,10例为健康儿童;用ZUCI-Protein Chip Data Analyze System分析软件进行数据处理;经留一法交叉验证,...