Section 3 Neuroblastoma

**63**

**Chapter 5**

Entity

**Abstract**

**1. Introduction**

**1.1 Background**

*Rakesh Mishra and Amit Agrawal*

Primary Central Nervous System

Neuroblastoma is one of the most common solid tumour in the paediatric age group. Central nervous system (CNS) involvement in neuroblastoma is commonly due to metastasis from the extracranial primary. Primary CNS Neuroblastoma (PCNS-NB) is a rare entity and highlights errors in development of neural crest cells and CNS. A lot has been published since the first description of PCNS-NB four decades ago. Over the years, neuroscientists, geneticists, and clinicians have improved the understanding of PCNS-NB. PCNS-NB is an enigmatic entity with variable presentation, epidemiology, clinical features and outcomes. Recent update in knowledge is seen in 2016 WHO classification of CNS tumours with reclassification of CNS neuroblastoma. It further subclassified different histological variants of PCNS-NB and its molecular correlates. Most common histological subtype of PCNS-NB is neuroblastoma followed by ganglioneuroblastoma. Studies support the view that younger age group, less number of lesions, ganglioneuroblastoma histology subtype and surgical management are good prognostic indicators. This chapter provides an updated overview of epidemiology, clinical features, histological and molecular diagnosis, and

**Keywords:** Primary central nervous system neuroblastoma, Ganglioneuroblastoma,

Neuroblastoma is one of the most common solid extracranial tumour in the paediatric age group. Key characteristics of neuroblastoma include onset at an early age, aggressive behaviour, tendency to metastasize, regress spontaneously in infancy, and variable presentation [1, 2]. Neuroblastoma is associated with grim prognosis with 60% of patients at presentation having only 5–15% chance of long term survival [3]. Most of the cases of central nervous system neuroblastoma are due to metastasis from the extracranial site. Primary central nervous system neuroblastoma (PCNS-NB) is uncommon as metastatic intracranial neuroblastoma (MIC-NB). It is essentialto understand that the manifestation of neuroblastoma varies with the site of origin [4, 5]. Therefore, a PCNS-NB has different epidemiology, clinical features, and outcomes compared to the MIC-NB. There is emerging evidence on various molecular and genetic profiling of neuroblastoma which dominates the clinical

outcomes of PCNS-NB in addition to the role of adjuvant therapy.

CNS PNET, CNS Neuroblastoma with FOX-R2, CNS embryonal tumours

Neuroblastoma: An Enigmatic
