Spinal glioneuronal tumor with neuropil‐like islands and meningeal dissemination: histopathological and radiological study of a pediatric case

Abstract

Cerebral and spinal location of glioneuronal tumors have been recently described as a novel type of primary CNS neoplasia. A distinctive rare form of glioneuronal tumors with neuropil-like islands (GTNI) have been reported to occur in the adult cerebrum, whereas spinal GTNI localization is extremely rare. In the present report we describe a case of a 15-month-old child with a spinal GTNI of the cervical region and meningeal dissemination. Histologically the tumor was composed of round, small neurocytic-like cells arranged around eosinophilic neuropil cores and embedded in a diffuse fibrillar glial component forming prominent "rosetted" neuropil islands displaying strong immunoreactivity for neuronal markers. Cerebral GTNI shows abundant glial components not rarely exhibiting anaplastic features that justify their inclusion within the group of diffuse astrocytomas. In contrast, including our case, spinal GTNI do not show histological evidence of anaplastic features and exhibits a significant neuronal component that may imply considering these lesions in a separate group. Nevertheless, due to their exceptional rarity, the natural history of these lesions is not yet fully understood, but spinal GTNI seems to have an unfavorable clinical course despite their benign histopathological features, which must be taken into account for appropriate treatment and follow-up of the patient.

An Individual Patient Data Meta-Analysis on Characteristics and Outcome of Patients with Papillary Glioneuronal Tumor, Rosette Glioneuronal Tumor with Neuropil-Like Islands and Rosette Forming Glioneuronal Tumor of the Fourth Ventricle

“…Most of these tumors are located in the supratentorial region (69%); however, spinal (23%) and even disseminated disease at primary diagnosis (8%) have been described by authors frequently (Table 2) [17], [21], [37], [41]. Showing variable contrast enhancement (Table 3), GNTNIs appear mostly as solid tumor in 73%, or, a smaller amount of 19%, cystic with a mural nodule with T2-hyperintensity (92%) and T1-hypointensity (92%) (Table 3) [4].…”

“…In contrast, GNTNI shows features of a high-grade glioma, mostly interpreted as astrocytic [43], but ependymal or oligodendroglial differentiation is possible [12]. Dispersed in this glial component, the most prominent feature of these tumors, rosetted neuropil-like islands, can be found [37].…”

Spinal cord glioneuronal tumor with neuropil-like islands with 1p/19q deletion in an adult with low-grade cerebral oligodendroglioma

“…With the exception of two spinal cord lesions, one in a 44-year-old woman [4] and one in a 48-year-old man [5], all tumors in adult patients have been intracranial [2,3,[6][7][8][9][10][11][12]. In contrast, all reported pediatric GTNIs have originated in the spinal cord [13][14][15]. Heretofore, no published cases of GTNI have exhibited wholearm 1p/19q deletions, as occur in many oligodendrogliomas [8], though two pediatric cases have demonstrated isolated 1p deletions [13,15].…”

A 46 Year‐Old Woman with a Spinal Cord Mass

“…Since then, it has been reported to occur in the adult cerebrum mainly. Whereas spinal GTNI localization is relatively rare . The tumor contained predominating micronodular neuropil‐like islands and the diffusely infiltrating glial component.…”