Infiltrative brainstem and cerebellar neurocytoma

Clinical prognostic factors for central neurocytoma and subgroup analysis of different treatment measures: A SEER database-based retrospective analysis from 2003 to 2019

Purpose

The study aimed to identify clinical prognostic factors affecting overall survival (OS) in patients with central neurocytoma (CN) and to determine independent prognostic factors in the subgroups of different treatment modalities using a retrospective analysis based on the SEER database from 2003 to 2019.

Materials and methods

Data regarding patients with CN, including basic clinical characteristics, treatment measures, and prognosis follow-up, were extracted from the SEER database. The prognostic variables for all patients were assessed using log-rank test as well as univariate and multivariate analyses based on the Cox proportional hazards model. The same statistical methods were used for analysis in different subgroups of gross total resection (GTR), subtotal resection (STR), no surgery, radiotherapy (RT), and no RT.

Results

In total, 413 patients were enrolled in this study. Tumor size, primary site surgery, and RT were independent prognostic factors in all patients with CN. In subgroup analyses, RT was not an independent prognostic factor in patients with GTR. However, sex and race were independent prognostic factors in patients with STR. Additionally, tumor size was an independent prognostic factor in patients who did not undergo surgery. Furthermore, sex and primary site were independent prognostic factors in patients who received RT. Size and primary site surgery were independent prognostic factors in patients without RT.

Conclusion

In our study, patients with small tumors or GTR or those who did not receive RT showed a better prognosis. GTR was the preferred treatment for CN. RT was not recommended for patients after GTR. Men and African American showed certain advantages after STR surgery. Tumors with a size of >4 cm were recommended for active treatment. In the RT subgroup, patients with tumors outside the ventricle or women had a poorer prognosis than those with tumors within the ventricle or men, respectively. These findings will help clinicians and patients understand the treatment and prognosis of CN visually and intuitively.

Extraventricular neurocytomas: a systematic review of the literature in the pediatric population

Extraventricular neurocytomas (EVNs) are rare neuroepithelial neoplasms of the central nervous system that were first described in 1997. Most studies in patients with EVNs have incorporated mixed age groups. The tumor's clinical behavior specifically in children has not been explored in depth, while a detailed statistical analysis has never been performed in this age group. Hence, we performed a systematic review to address possible prognostic factors and the appropriate management in children with EVNs. Relevant studies were identified by searching the MEDLINE and SCOPUS databases. We included studies concerning patients 18 years of age or younger who were histologically diagnosed with EVNs. A total of 52 studies with 79 patients were included. The mean age of the patients was ~ 10 years with a male predilection (~ 2:1). Most of these tumors were located in the frontal (49%) lobe. We observed that gross total resection of the tumor was significantly lower in cases of atypical EVNs (p < 0.05). Additionally, atypical EVNs were associated with worse overall survival compared to typical EVNs (p = 0.05). Children 4 years of age or under had a worst outcome (p = 0.001). The patient's sex and the extent of the tumor's resection did not appear to affect the prognosis in a statistically significant manner. Contrary to the results of previous studies, the use of adjuvant radiotherapy or chemotherapy for the treatment of EVNs was not associated with better outcomes in the pediatric population. Thus, a less aggressive management of children with EVNs compared to the adult population is suggested.

Imaging of extraventricular neurocytoma: a systematic literature review

OBJECTIVE

Extraventricular neurocytoma (EVN) was firstly described in 1997. The current literature regarding imaging of EVN is limited to sporadic case reports and case series. EVN is still poorly considered in the differential diagnosis by neuroradiologists, thus diagnosis remains challenging. In this systematic review, we summarize and discuss computed tomography (CT) and magnetic resonance imaging (MRI) features of EVN cases described in the literature, in order to provide useful informations to neuroradiologists. To the best of our knowledge, this is the most extensive review about imaging of EVN.

MATERIALS AND METHODS

A systematic review of the literature about imaging of EVN cases was done. Only case reports or case series in which imaging (CT and/or MRI) features were deeply described were included in the revision. Eligibility of studies was assessed independently by two authors and any disagreements resolved by discussion.

RESULTS

Our search strategy revealed 224 articles. After implementation of inclusion and exclusion criteria, 35 studies were considered, and a total of 79 cases of EVN were analyzed.

CONCLUSION

EVN has not specific characteristics, with a large and variable imaging spectrum. Usually it appears as a large tumor, with diameters superior to 40 mm, frequently involving the frontal lobe. CT density and MRI signal intensity typically mirror the presence of cystic, solid, or calcified elements; contrast enhancement is visible in 87% of cases. Today, diagnosis of EVN with only imaging techniques is not univocal; neuroradiologists can only suspect this type of lesion, while the definitive diagnosis remains histological.

Congenital Extra-Ventricular (Ganglio)Neurocytoma of the Brain Stem: A Case Report

Extraventricular neurocytoma (EVN) is an extremely rare tumor of neuroglial origin with a tendency toward ganglionic or glial differentiation. In the 2016 World Health Organization Classification, EVN was classified as a grade II tumor and described as a neoplasm with good outcome. However, the presence of cellular atypia is an important unfavorable prognostic factor. Here, we describe the first case of a patient with a congenital EVN localized in the brainstem. After a sub-total resection, his disease rapidly progressed despite several chemotherapies, including molecular targeting approaches. He died 13 months after diagnosis. In conclusion, we report an atypical case of EVN presenting an extremely aggressive behavior, despite the absence of cellular atypia. The brainstem origin and the age of the patient may have represented two important prognostic factors for our patient.

Central Neurocytoma: A Review of Clinical Management and Histopathologic Features

Central neurocytoma (CN) is a rare, benign brain tumor often located in the lateral ventricles. CN may cause obstructive hydrocephalus and manifest as signs of increased intracranial pressure. The goal of treatment for CN is a gross total resection (GTR), which often yields excellent prognosis with a very high rate of tumor control and survival. Adjuvant radiosurgery and radiotherapy may be considered to improve tumor control when GTR cannot be achieved. Chemotherapy is also not considered a primary treatment, but has been used as a salvage therapy. The radiological features of CN are indistinguishable from those of other brain tumors; therefore, many histological markers, such as synaptophysin, can be very useful for diagnosing CNs. Furthermore, the MIB-1 Labeling Index seems to be correlated with the prognosis of CN. We also discuss oncogenes associated with these elusive tumors. Further studies may improve our ability to accurately diagnose CNs and to design the optimal treatment regimens for patients with CNs.

Behavioral disorders as unusual presentation of pediatric extraventricular neurocytoma: report on two cases and review of the literature

BACKGROUND

Extraventricular neurocytomas (EVNs) are rare parenchymal brain tumors, distinct from central neurocytomas that are typically located within the supratentorial ventricular system. Seizures and headache represent the most common symptoms of extraventricular neurocytomas in the cerebral hemisphere both in adult and pediatric population.

CASE PRESENTATION

We describe two cases of pediatric EVN with clinical onset characterized by behavioral and attention deficit/ hyperactivity disorders. The association between behavioral/attention disorders in childhood and the presence of a frontal neurocytoma has never been described before. Furthermore, inappropriate levels of inattention, hyperactivity and impulsivity are common among the neurobehavioral and developmental disorders in childhood. We reviewed 43 pediatric cases of extraventricular neurocytoma included in the PubMed database and their clinical presentation, and we never found this unusual relationship.

CONCLUSION

In childhood, the attention/hyperactivity disorders seem to be often over-diagnosed. When these deficits are more subtle and do not well-fit in a specific neurocognitive disorder, the clinicians should have a suspicion that they might mask the clinical features of a frontal lesion. This paper is focused on the clinical presentation of the extraventricular neurocytoma and the possible organic etiology of an attention and hyperactivity deficit.

Primary central neurocytoma of the mesencephalic tectum in a pediatric patient

PURPOSE

Neurocytomas are tumors or neuronal differentiation, typically located within the supratentorial ventricular system. The extraventricular location is uncommon. A limited number of cases involving the brainstem have been reported and may be misdiagnosed as brainstem gliomas. Furthermore, midbrain neurocytomas are extremely rare, and no similar cases in pediatric patients have been reported in the literature to date. Brainstem location of neurocytomas often precludes gross total removal of the lesion, and in these cases, adjuvant therapies may be helpful.

METHODS

We report a case of a 16-year-old child who presented with signs and symptoms of increased intracranial pressure. The magnetic resonance imaging study demonstrated the presence of a primary mesencephalic tectum lesion causing obstructive hydrocephalus. The patient underwent emergent ventriculoperitoneal shunt implantation, resolving the hydrocephalus and the clinical symptoms. The lesion was partially removed through a suboccipital craniotomy and supracerebellar infratentorial approach to the mesencephalic tectum, without intraoperative complications.

RESULTS

Histological examination of the lesion was consistent with the diagnosis of extraventricular neurocytoma. The patient was referred to the oncology department for additional treatment with Gamma Knife radiosurgery.

CONCLUSIONS

Although brainstem neurocytoma is rare, this case demonstrates that it should be included in the differential diagnosis of brainstem gliomas. Because of brainstem tumor location, complete surgical removal may be challenging or not possible, with a high risk of postoperative neurological deficits. Adjuvant therapies may prevent local tumor growth in cases of tumor remnants or recurrences following microsurgery in selected cases.

Visual and auditory hallucinations revealing cerebellar extraventricular neurocytoma: uncommon presentation for uncommon tumor in uncommon location

OBJECTIVE

Visual and auditory hallucinations in relation to a cerebellar tumor are rarely reported in children. Primary origin of extraventricular neurocytoma (EVN) in the cerebellum is very rare.

CLINICAL PRESENTATION

We report on a case of a cerebellar EVN in a 13-year-old girl with the initial symptoms of psychiatric manifestations for more than 2 months. Magnetic resonance imaging of the brain revealed a patchy enhanced tumor in the paramedian left cerebellar region. No obstructive hydrocephalus was noted.

INTERVENTION

Total surgical removal of the tumor was performed. The tumor was initially diagnosed as an oligodendroglioma. After special immunohistochemical studies, the final definitive diagnosis was an EVN without isocitrate dehydrogenase mutation.

CONCLUSION

EVNs located in the cerebellum are extremely rare. We discuss the clinical symptoms and histological-immunohistochemical features of this rare tumor in that rare location.

Extraventricular neurocytoma in pediatric populations: A case report and review of the literature

Extraventricular neurocytomas (EVNs) are rare neuronal tumors included in the definition of neoplasms in the 2007 World Health Organization classification of tumors of the central nervous system. Although a small case series of EVNs in adults has been previously reported, EVNs in pediatric populations are extremely rare. The current case report presents the clinicopathological features of an EVN in a 2-year-old female who presented with nausea and vomiting that had lasted for five days. In addition, an analysis of the imaging features, histology, treatment and prognosis of these reported rare lesions is presented. Immunohistochemically, EVNs are characterized by the robust expression of synaptophysin, but with a lack of oligodendrocyte transcription factor 2, isocitrate dehydrogenase enzyme isoform 1 (IDH1) R132/IDH2 R172 mutations and p53 immunoexpression. The treatment for EVNs in pediatric and adult populations is gross total resection, with post-operative radiation reserved for subtotal resection or recurrent disease. In addition, drop metastasis must be carefully avoided.