Treatment of Central Neurocytoma

Abstract

Objective: Central neurocytomas (CNs), classified as CNS (central nervous system) grade 2 tumors, are exceptionally rare tumors, accounting for approximately 0.1-0.5% of all intracranial neoplasms, and are typically characterized by a benign clinical course and frequent association with hydrocephalus. This study aims to present a comprehensive analysis of surgical and adjuvant therapies for CN. Methods: The study comprised all patients who underwent microsurgical tumor removal in our center over the past decade (2013-2023). Clinical manifestations, surgical and adjuvant therapy approaches, MRI and histological findings, clinical outcomes, and recurrence-free survival were evaluated. Results: A total of eleven patients (six men, mean age of 28.0 years; five women, mean age of 53.6 years) underwent surgical treatment. Intraventricular tumors were the most common (72.7%, n = 8). The predominant presenting symptoms were headache and visual disturbances. All tumors exhibited contrast enhancement on MRI. Hydrocephalus was present in five patients. The Ki67 proliferation index ranged from 2% to 10%, with nine patients exhibiting Ki67 > 3%. The median recurrence-free survival was 38.0 months (IQR: 25.0-53.0). The most severe postoperative complications included aphasia, hemiparesis, and memory impairment, resulting in a postoperative Karnofsky Performance Status (KPS) below 70% in five patients. Follow-up assessments showed significant symptomatic improvement in all affected patients. Conclusions: Gross total resection is the recommended first-line therapy with favorable neurological outcomes and for atypical CN as well. Adjuvant radiotherapy should be reserved for tumor progression and recurrence. The role of adjuvant chemotherapy remains unclear, but it may be an option for CN with a high proliferation index.

Keywords: adjuvant radiotherapy; atypical central neurocytoma; central neurocytoma; pseudorosette.

Figure 1

Intraventricular CN with hydrocephalus ((A–C): preoperative T1-weighted MRI with gadolinium contrast; (D–F): postoperative T1-weighted MRI with gadolinium contrast). These representative images are from case 1, a 31-year-old male who presented with headaches and cognitive deficits over the previous eight weeks. All tumors demonstrated contrast enhancement on MRI, with some cases exhibiting diffuse enhancement.

Figure 2

Histopathological analysis revealed a neuroectodermal tumor with a moderate to slightly increased cellularity on HE staining (A,B). The tumor cells were positive for NeuN (C). Neurofilament staining highlighted only the surrounding brain tissue, clearly delineating the tumor from adjacent tissue (D). GFAP staining showed positive labeling in only a few infiltrated resident astrocytes (E). The Ki-67 proliferation index was approximately 1% (F). The histopathologic presentation was based on the specimens of case 5. Abbreviations: HE: hematoxylin–eosin staining, GFAP: glial fibrillary acidic protein, NeuN: Hexaribonucleotide Binding Protein-3, Ki-67: marker of proliferation.

Figure 3

Clinical and neurological statuses were assessed preoperatively, postoperatively, and during follow-up. Follow-up data showed a significant improvement in symptoms for all patients, with a KPS of 70% or higher.

Figure 4

The Kaplan–Meier curve illustrates recurrence-free survival in the two groups, i.e., those treated with surgery alone (median: 26.5 months) and those who received surgery followed by adjuvant radiotherapy (median: 40.0 months). (log rank: p = 0.922).

Figure 5

Radiographic findings of case 11. (A) Preoperative T1 MRI with a contrast agent. (B) Postoperative MRI on the first postoperative day. (C) Three years of follow-up MRT after adjuvant radiation.