A Case of Suprasellar Papillary Glioneuronal Tumor Mimicking Craniopharyngioma

Abstract

Papillary glioneuronal tumor (PGNT) is a low-grade biphasic neoplasm with astrocytic and neuronal differentiation. This tumor occurs most commonly in the frontal and temporal lobes, close to the ventricles, and rarely in the cerebellum, brainstem, and pineal gland. However, there has been no report of this tumor in the suprasellar region to date. In this paper, we report a case of PGNT in the suprasellar region in a 16-year-old girl. Magnetic resonance imaging (MRI) revealed a cystic tumor with calcification that progressed from the anterior skull base to the suprasellar and temporal regions. Preoperatively distinguishing this tumor from craniopharyngioma was difficult because of the patient’s age, localization of the tumor, and neuroimaging results. This case showed a backward shift of the chiasma, which is observed in only 4.7% of craniopharyngioma, as well as normal endocrine findings. Endocrinological examination and an MRI evaluation of the chiasmal shift may be useful for discrimination.

Papillary Glioneuronal Tumor of Third Ventricle Endoscopically Treated: Case Report and Review of Literature

“…Regarding its topography, radiographic appearance of PGNT does not have any distinct characteristics and resembles to the one of ganglioglioma [16]. It may be surmised that this glioneuronal tumor may arise from anywhere in the central nervous system and mostly supratentorial locations close to the ventricles [2,8]. The most preferred sites for PGNT are temporal, frontal, parietal lobes and less often it is developed in more than one lobes or into ventricles [2,8,12,17].…”

“…Glial appearance has an immunophenotype of GFAP+, S100+ and nestin+, while neuronal components are explained by synaptophysin+, neuron-specific enolase+, and class III beta-tu-bulin+ [5]. Molecular analysis has demonstrated the association of PGNT with the presence of a fusion gene SCL44A1/PRKCA, which seems to be a common characteristic of most PGNTs with a high diagnostic value and detectable by FISH [2,11,15]. In the new WHO classification in 2021, PRKCA is regarded as a key-diagnostic gene for papillary glioneuronal tumors [1].…”

“…Concerning its radiological appearance, literature review suggests a tumor usually presented as a demarcated and heterogeneously contrast-enhanced mass with some calcification. Occasionally, PGNT consists of cystic formation and hemorrhage with incidents of 86% and 10% respectively [2,16]. Only slight edema may be present.…”

“…It may be surmised that this glioneuronal tumor may arise from anywhere in the central nervous system and mostly supratentorial locations close to the ventricles [2,8]. The most preferred sites for PGNT are temporal, frontal, parietal lobes and less often it is developed in more than one lobes or into ventricles [2,8,12,17]. The periventricular association of PGNT in the majority of cases suggests its possible origin from the germinative zone in the subependymal plate and explains its presentation with symptoms of obstructive hydrocephalus [3,8,17].…”

“…Based on the new 2021 edition of the WHO classification of CNS tumors, PGNT is considered a grade I tumor, in the category of glioneuronal and neuronal tumors [1]. The literature surrounding this tumor is mostly based on case reports and epidemiologic data demonstrate that the rare PGNT accounts only for 0,02% of intracranial oncology [2].…”