Clinicopathologic and neuroradiologic studies of papillary glioneuronal tumors

Papillary glioneuronal tumor: a case report of the cerebral aqueduct and review of literature

Papillary glioneuronal tumour is an entity described as grade I neuronal-glial tumour by the World Health Organization. Headaches, seizures, vomiting, language or visual disturbances, and hemiparesis are the most common clinical findings. This tumour typically presents as cystic with enhancing mural nodule in the cerebral hemisphere. In this paper, we reported a case of a papillary glioneuronal tumour in a young adult whose magnetic resonance imaging revealed a solid tumour in the cerebral aqueduct. The tumour was totally resected surgically 13 years ago. The histological and immunohistochemical examination determined the diagnosis. No further therapy was necessary. Currently, the patient presents no neurologic signs or symptoms and there is no radiologic evidence of tumour relapse. The case of papillary glioneuronal tumour reported here displayed unusual location and radiologic features. The long duration of follow-up of this case with no tumour relapse enhances that the preferred management for this type of tumour is its total surgical resection.

Papillary Glioneuronal Tumor Masquerading as Malignant Brain Tumors: A Case Report

Papillary glioneuronal tumor (PGNT) is a low-grade biphasic tumor that is composed of glial fibrillary acidic protein (GFAP)-positive glial cells and synaptophysin-positive neurons. We report a case of PGNT occurring in the right occipital lobe of a 48-year-old woman who presented with acute headache and left homonymous hemianopsia, the latter of which was difficult to distinguish from malignant brain tumors because of peritumoral brain edema, intratumoral hemorrhage, and intraoperative fluorescence staining. PGNT should be included as one of the differential diagnoses in cases where the tumor shows hemorrhagic change despite decreased perfusion in arterial spin labeling MRI.

Update on Circumscribed Gliomas and Glioneuronal Tumors

Well-circumscribed intra-axial CNS tumors encompass a wide variety of gliomas and glioneuronal tumors, usually corresponding to WHO grades I and II. Nonetheless, sometimes high-grade 'diffuse' gliomas such as gliosarcoma and giant cell glioblastoma can be relatively circumscribed but are often found to have foci of diffuse infiltration on careful examination, harboring distinct molecular alterations. These tumors are excluded from the discussion in this chapter with the current review emphasizing on lower-grade entities to include a brief description of their histology and associated molecular findings. Like elsewhere in brain biopsy evaluation, imaging is crucial and acts as a surrogate to gross examination. Given the circumscribed nature of these tumors, surgery alone is the mainstay treatment in most entities.

Operative Procedure in a Suprasellar Paediatric Lesion of the Optic Chiasm with Hydrocephalus Caused by a Papillary Glioneuronal Tumour

INTRODUCTION

Paediatric tumours in the sellar and parasellar regions present clinical and surgical challenges due to anatomical position and behaviour. We illustrate a rare case which caused obstructive hydrocephalus.

CASE PRESENTATION

The study included a 14-year-old girl with a glioneuronal tumour (40 mm) originating from the optic chiasm, obliterating the aqueduct, with consequent triventricular hydrocephalus. The patient underwent extended endoscopic endonasal surgery and repair of the skull-base deficiency using a multi-layer technique with fascia lata. The 12-month follow-up showed no complications or recurrences, with recovery in visual acuity.

CONCLUSION

The immediate placement of external ventricular drainage, in combination with an extended trans-sphenoidal approach, is a safe and feasible option to treat suprasellar paediatric lesions with hydrocephalus.

Acute presentation of papillary glioneuronal tumor due to intra-tumoral hemorrhage in a toddler: an odd presentation of a rare pathology

BACKGROUND AND IMPORTANCE

Papillary glioneuronal tumor is a recently known entity in central nervous system tumors. These benign WHO grade I tumors are mostly seen in young adults. Pediatric PGNT is rare and there is no report of these tumors in toddlers. Headache, nausea/vomiting and seizure are most common clinical symptoms. Acute presentation with focal neurological deficits or loss of consciousness are not amongst the expected presentations. These tumors are typically cystic with enhancing mural nodule. Although case with chronic intermittent microhemorrhages are reported in the literature but overt intra-tumoral hemorrhage is an odd radiological presentation with just one reported case in the literature.

CLINICAL PRESENTATION

We present an extremely rare case of PGNT presenting with sudden onset hemiparesis and impaired consciousness due to acute intra-tumoral hemorrhage in a toddler which was surgically treated with favorable outcome.

CONCLUSION

PGNTs can also be seen in very young children even in toddlers. Also, it should be kept in mind that these tumors have potential for overt intra-tumoral hemorrhage and acute presentation with focal neurological deficits mimicking more common pathologies which should be considered to plan optimal patient management.

Imaging of Neuronal and Mixed Glioneuronal Tumors

Neuronal and mixed glioneuronal tumors represent a group of neoplasms with varying degrees of neural and glial elements. Their age of presentation varies, but they are most commonly seen in children and young adults. With the exception of anaplastic ganglioglioma and other atypical variants, most lesions are low grade; however, they can have significant morbidity because of seizures, mass effect, or difficult to treat hydrocephalus. Although many tumors show overlapping clinical and imaging features, some have relatively distinctive imaging characteristics that may aid in narrowing the differential diagnosis. In this review, we discuss relevant clinical and pathologic characteristics of these tumors and provide an overview of conventional and advanced imaging features that provide clues as to the diagnosis.

Uncommon low-grade brain tumors

The 2016 World Health Organization (WHO) classification of primary central nervous system (CNS) tumors includes numerous uncommon (representing ≤1% of tumors) low-grade (grades I-II) brain neoplasms with varying clinical behaviors and outcomes. Generally, gross tumor or maximal safe resection is the primary treatment. Adjuvant treatments, though their exact role is unknown, may be considered individually based on pathological subtypes and a proper assessment of risks and benefits. Targetable mutations such as BRAF (proto-oncogene B-Raf), TRAIL (tumor necrosis factor apoptosis inducing ligand), and PDGFR (platelet derived growth factor receptor) have promising roles in future management.

Magnetic resonance imaging findings of mixed neuronal-glial tumors with pathologic correlation: a review

Mixed neuronal-glial tumors are rare, and MRI diagnosis of them presents a challenge. In this review, we discuss the MRI findings of ganglioglioma, anaplastic ganglioglioma, desmoplastic infantile ganglioglioma, papillary glioneuronal tumor, rosette-forming glioneuronal tumor, and primary diffuse leptomeningeal glioneuronal tumor with clinicopathologic correlation. There is overlap of imaging features both with each other and some other tumors, which complicates diagnosis. The combination of imaging findings and the age, location, and appropriate clinical picture should allow the radiologist and the clinicians to raise a provisional diagnosis of a mixed neuronal glial tumor, and guide patient management.

Enlargement of papillary glioneuronal tumor in an adult after a follow-up period of 10 years: a case report

Papillary glioneuronal tumor (PGNT) is a rare brain tumor grouped under mixed glioneuronal tumors according to the World Health Organization Classification of the Central Nervous System. The natural history of this pathology is not yet well documented. We report a case of PGNT that increased in size after a follow-up period of 10 years. An enlarged cyst wall and nodule showed a low intensity signal on T2*-weighted, suggesting hemorrhage during the clinical course. Characteristic pathological findings along with absence of BRAF^V600E mutation identified the tumor as PGNT. The tumor characteristics of PGNT are discussed based on the presented case, with reference to the existing literature.

Papillary glioneuronal tumors: A radiopathologic correlation

OBJECTIVE

Papillary glioneuronal tumors (PGNT) are a rare and recently recognized tumor entity. The neuroimaging findings were reviewed to determine if any specific findings emerge to assist a preoperative diagnosis of PGNT.

MATERIALS AND METHODS

Seven histologically confirmed cases of PGNT were evaluated from 2004 to 2014. Clinical, neuroimaging and histological findings were reviewed and tabulated.

RESULTS

Headache and seizures were observed in 4 patients (57.1%) each. The majority (n=5, 71.4%) of lesions were periventricular and located in temporal lobe with 57.1% cases being solid cystic (n=4), and 42.9% being purely solid (n=3). Calcification and hemorrhage were noted in 3 cases (42.9%) and 5 cases (71.4%) respectively. The most frequent imaging feature was the presence of septations in the cystic component that enhanced on contrast which correlated with long pseudopapillary projections into the cyst cavity on histopathology. The solid inner component demonstrated heterogeneous enhancement. One case with tumor recurrence demonstrated hemorrhage with superficial siderosis, patchy diffusion restriction, raised choline and focal areas of raised perfusion which correlated on histopathology with increased cellularity and anaplasia.

CONCLUSION

Presence of cystic mass in periventricular location with septations and a solid inner component should raise a suspicion of PGNT on neuroimaging.

Adult Brain Tumors and Pseudotumors: Interesting (Bizarre) Cases

Some brain tumors results are interesting due to their rarity at presentation and overwhelming imaging characteristics, posing a diagnostic challenge in the eyes of any experienced neuroradiologist. This article focuses on the most important features regarding epidemiology, location, clinical presentation, histopathology, and imaging findings of cases considered "bizarre." A review of the most recent literature dealing with these unusual tumors and pseudotumors is presented, highlighting key points related to the diagnosis, treatments, outcomes, and differential diagnosis.

Cerebral hemispheric low-grade glial tumors in children: preoperative anatomic assessment with MRI and DTI

PURPOSE

The aims of this study are to analyze how the nature and the behavior of low-grade glial tumors (LGGT) in children may correlate with the anatomy of the cerebral hemispheres and to evaluate the consequent impact of diffusion tensor imaging (DTI) techniques in the presurgical assessment.

METHODS

This is a combined review of a series of 155 cases of LGGT and of the recent literature on the subject.

RESULTS

The cases retrieved from our data bank were divided in central hemispheric tumors (basal ganglia and thalami) (36 cases), glioneuronal cortical-based tumors (49 cases), and glial tumors of the cerebral mantle (70 cases). A close correlation was found in the thalamus between the primary location of the tumor (juxta-ventricular, inferior, lateral, bilateral) and its extension (ventricular lumen, midbrain and mesial temporal, globus pallidus, respectively) which may relate to the connectivity. Among the glioneuronal tumors, most gangliogliomas were located in the temporal lobe and especially in the mesial temporal structures. In addition, the morphologic feature of the ganglioglioma was different there from the neocortical areas. As a complementary approach, DTI data may assist in evaluating the structure and the extension of the LGGT, in addition to planning the surgical strategy.

CONCLUSIONS

In the cerebral hemispheres like in the rest of the central nervous system, there is some degree of correlation between the anatomy and the nature, appearance, and behavior of the LGGT in children.

Zinc and zinc-containing biomolecules in childhood brain tumors

Zinc ions are essential cofactors of a wide range of enzymes, transcription factors, and other regulatory proteins. Moreover, zinc is also involved in cellular signaling and enzymes inhibition. Zinc dysregulation, deficiency, over-supply, and imbalance in zinc ion transporters regulation are connected with various diseases including cancer. A zinc ion pool is maintained by two types of proteins: (i) zinc-binding proteins, which act as a buffer and intracellular donors of zinc and (ii) zinc transporters responsible for zinc fluxes into/from cells and organelles. The decreased serum zinc ion levels have been identified in patients suffering from various cancer diseases, including head and neck tumors and breast, prostate, liver, and lung cancer. On the contrary, increased zinc ion levels have been found in breast cancer and other malignant tissues. Zinc metalloproteomes of a majority of tumors including brain ones are still not yet fully understood. Current knowledge show that zinc ion levels and detection of certain zinc-containing proteins may be utilized for diagnostic and prognostic purposes. In addition, these proteins can also be promising therapeutic targets. The aim of the present work is an overview of the importance of zinc ions, zinc transporters, and zinc-containing proteins in brain tumors, which are, after leukemia, the second most common type of childhood cancer and the second leading cause of death in children after accidents.