Central neurocytoma case reports

Atypical central neurocytoma with extracranial metastases is a rare variant of benign central neurocytoma (CN). No definitive course of treatment exists for atypical CN. We report a unique case of atypical CN with concomitant pituitary macroadenoma and subsequent metastases to the spine. The patient received craniospinal radiation therapy. Close-follow up post-tumor-resection may be advised to monitor for drop metastases. To the best of our knowledge, this is the only case reported of atypical CN with drop metastases to the spine concomitant with pathological-proven pituitary macroadenoma ¹⁾.

A 58-year-old male presented with progressive decline in cognition and gait. Subsequent Magnetic Resonance Imaging revealed obstructive hydrocephalus secondary to a posterior third ventricular tumor. An endoscopic biopsy and concurrent cerebrospinal fluid diversion by ETV was performed. Pathological analysis was consistent with a CN with positivity to Synaptophysin. MIB-1 proliferation index was 1%. There was good clinical recovery, and the patient underwent adjuvant stereotactic radiosurgery 1.5 months post-surgery.

Due to the rarity of CNs arising from the third ventricle, there are only three previous reports of these approached endoscopically. Such a technique allows for good visualisation of the lesion, and therapeutic ETV to relieve obstructive hydrocephalus. This case supports this approach as a valid, minimally invasive option. Additionally, this is the first case to report the MIB-1 proliferation index, contributing to future outcome evaluation of endoscopic approaches to typical (MIB-1 < = 2%) verses atypical (MIB-1 > 2%) CNs.

Endoscopic biopsy with concurrent ETV and adjuvant stereotactic radiosurgery is a valid treatment option for deep seated isolated small posterior third ventricular CNs ²⁾.

Central neurocytomas (CNs) occurs typically in the lateral ventricle, adjacent to the septum pellucidum and foramen of Monro. The clinical presentation varies and many are incidentally detected. The incidence of spontaneous hemorrhage at presentation is rare. Chandshah et al. reported a case of the intraventricular lesion with bleed which was operated on an emergency basis as it caused obstructive hydrocephalus and the patient was in altered sensorium. The exact cause of hemorrhage in CNs is not known, and the previously discussed explanations are discussed ³⁾

Only 3 previous cases in which CN presented with co-occurring psychotic symptoms were found in the PubMed database. This report presents the case of a 27-year-old patient with paranoid syndrome without neurological symptoms, in whom magnetic resonance imaging confirmed a large intracranial tumor located predominantly in the right lateral ventricle and third ventricle reaching down to the hypothalamus. Resection of the tumor (histopathologically a CN) resulted in complete remission of the psychotic symptoms. This case supports the need for neuroimaging in all patients with first-episode psychosis because of the possibility of neurologically silent brain tumors. Quick diagnosis in such cases is crucial for the selection of treatment methods and prognosis ⁴⁾.

Kawakami et al. present the first case of central neurocytoma with a component suggesting ependymal-like differentiation as an unclassified glioneuronal tumor. The patient was a 26-year-old Japanese man with a brain tumor extending from the frontal wall of the bilateral lateral ventricles to the corpus callosum. Histologically, the tumor's neuronal component consisted of small bland looking cells with fine, delicate, neuropil-like processes forming a rosette structure; its glial component consisted of tumor cells with thick processes arranged around the thinly walled vessels, resulting in a perivascular pseudo-rosette formation and indicating ependymal-like differentiation. Immunohistochemically, the cytoplasm of the tumor cells with ependymal-like features was positive for glial fibrillary acidic protein and negative for synaptophysin, while the tumor component with neuronal features showed the opposite immunohistochemical staining pattern. Most of the tumor cells were positive for Olig2, but EMA, D2-40, CD99, p53, and mutant IDH-1 (R132H) were totally negative. Its Ki-67 labeling index was less than 1 %. Histologically, this tumor was diagnosed as a central neurocytoma with an ependymoma-like glial component, and its tumor grade was estimated at grade II. The tumor location, infiltrating the corpus callosum, and histology were distinctive and might represent a peculiar subtype of glioneuronal tumor ⁵⁾.