Primary Central Nervous System Neuroblastoma: An Enigmatic Entity

Abstract

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

A rare case of a primary central nervous system neuroblastoma mimicking a trigeminal schwannoma in an adult

“…PCN-NB is a sporadic intracranial and spinal neuroblastoma manifestation that mostly affects neonates and adolescents [1 , 4 , 6 , 7] . PCN-NB was previously classified as a primitive neuroectodermal tumor, a group of intracranial neoplasms occurring in pediatrics with similar pathological characteristics, including pineoblastoma, ependymoblastoma, medulloblastoma, medulloepithelioma, and primary cerebral neuroblastoma [4 , 5 , 7 , 11] .…”

“…Neuroblastoma typically arises in primordial neural crest cells that naturally grow in the adrenal medulla and sympathetic nerve ganglia, explaining the tumor's behavior in several typical locations. An error in developing neural crest cells and the CNS gives a nearly closed door to generate PCN-NB [6] . This abnormal development of neural crest cells also explains why neuroblastoma is more common in children than adults [1 , 4 , 6 , 7] .…”

“…To our knowledge, only a few PCN-NB cases have been reported, with an incidence of 0.12 cases per 1,000,000 population annually. Most cases involve pediatric patients and only sporadically adults [1 , 2 , 4 , 6 , 7] . Lu et al.…”

“…PCN-NB's clinical symptoms are nonspecific and primarily depend on the tumor's location, including headache, neuro-deficit symptoms, seizure, and even altered consciousness in cases with sudden intra-tumoral hemorrhage [6] . Some studies indicate that PCN-NB often arises in the supratentorial brain parenchyma [6 , 7] . Tietze et al.…”

“…However, no reliable and specific imaging characteristic has been found to differentiate PCN-NB from other malignant brain neoplasms. Computed tomography and magnetic resonance imaging (MRI) of intracranial PCN-NBs often show a large lobulated mass with a heterogeneous structure comprising intratumoral cystic degeneration, calcification, and hemorrhage, with a moderate-to-strong enhancement of solid components and frequent peritumoral edema [6 , 9] . In addition, PCN-NBs manifest several malignant neoplasm aspects, such as low apparent diffusion coefficient (ADC) values due to restricted water molecule diffusion in high cellularity lesions, rapid expansion, and intratumoral hemorrhage [6 , 9 , 10] .…”