Astroblastoma - a rare and challenging tumor: a case report and review of the literature

A case of disseminated spinal astroblastoma harboring a MAMLD1::BEND2 fusion

Astroblastoma, MN1-altered, is a rare neoplasm of the central nervous system (CNS). This malignancy shares similar histopathological features with other CNS tumors, including ependymomas, making it challenging to diagnose. DNA methylation profiling is a new and robust technique that may be used to overcome this diagnostic hurdle. We report the case of a now 25-year-old female diagnosed with what was initially called an ependymoma located in the cervical spine at the age of 2 years old. After initial resection, the tumor recurred multiple times and within 2 years of diagnosis had disseminated disease throughout the brain and spinal cord. She has now undergone over two decades of treatment, including multiple surgical resections, radiation therapy, and administration of numerous chemotherapeutic agents. In 2021, the patient presented to our institution with lumbosacral radicular symptoms due to enlarging lesions within the lumbosacral spine. Reexamination of formalin-fixed, paraffin-embedded material from the patient's tumor using genomic DNA methylation profiling resulted in a diagnostic change from grade III anaplastic ependymoma to astroblastoma, MN1-altered. This work describes another confirmed case of astroblastoma, MN1-altered, to the growing body of literature.

Awake resection of recurrent astroblastoma with intraoperative 5-ALA-induced fluorescence: illustrative case

BACKGROUND

Astroblastoma is a rare neoplasm characterized as a circumscribed glial neoplasm most often arising in the frontoparietal cerebral hemispheres in older children.

OBSERVATIONS

We report an intriguing case of an astroblastoma recurrence 21 years after gross-total resection and radiation. A 32-year-old right-handed female presented to the emergency department for a generalized tonic-clonic seizure. She had a history of bipolar disorder, intractable migraines, and prior seizures linked to an astroblastoma previously resected three times. Magnetic resonance imaging on the current visit showed growth of the recurrent lesion to a 3.8-cm maximal diameter. Left-sided awake craniotomy was performed to remove the tumor while using speech mapping and 5-aminolevulinic acid (5-ALA). Targeted next-generation sequencing of the tumor revealed in-frame MN1::BEND2 fusion transcripts.

LESSONS

We found that 5-ALA can be used in astroblastoma patients to assist in gross-total resection, which is important for long-term survival. Our astroblastoma case demonstrated classic astroblastoma morphology, with typical perivascular astroblastic rosettes, and was brightly fluorescent after 5-ALA administration.

Radiology-Pathology and Surgical Correlation in Astroblastoma

Astroblastoma is a rare astrocytic glial neoplasm that affects mainly young girls, peaking between 10 and 30 years of age, with low- and high-grade manifestations. Imaging characteristics are well-described, but histopathologic and, more recently, molecular analysis is fundamental to establish the diagnosis, now based on MN1 alterations. We describe a case with typical imaging and histologic features of an MN1-altered astroblastoma.

Early ependymal tumor with MN1-BEND2 fusion: a mostly cerebral tumor of female children with a good prognosis that is distinct from classical astroblastoma

PURPOSE

Review of the clinicopathologic and genetic features of early ependymal tumor with MN1-BEND2 fusion (EET MN1-BEND2), classical astroblastomas, and recently described related pediatric CNS tumors. I also briefly review general mechanisms of gene expression silencing by DNA methylation and chromatin remodeling, and genomic DNA methylation profiling as a powerful new tool for CNS tumor classification.

METHODS

Literature review and illustration of tumor histopathologic features and prenatal gene expression timelines.

RESULTS

Astroblastoma, originally descried by Bailey and Cushing in 1926, has been an enigmatic tumor. Whether they are of ependymal or astrocytic derivation was argued for decades. Recent genetic evidence supports existence of both ependymal and astrocytic astroblastoma-like tumors. Studies have shown that tumors exhibiting astroblastoma-like histology can be classified into discrete entities based on their genomic DNA methylation profiles, gene expression, and in some cases, the presence of unique gene fusions. One such tumor, EET MN1-BEND2 occurs mostly in female children, and has an overall very good prognosis with surgical management. It contains a gene fusion comprised of portions of the MN1 gene at chromosomal location 22q12.1 and the BEND2 gene at Xp22.13. Other emerging pediatric CNS tumor entities demonstrating ependymal or astroblastoma-like histological features also harbor gene fusions involving chromosome X, 11q22 and 22q12 breakpoint regions.

CONCLUSIONS

Genomic DNA profiling has facilitated discovery of several new CNS tumor entities, however, traditional methods, such as immunohistochemistry, DNA or RNA sequencing, and cytogenetic studies, including fluorescence in situ hybridization, remain necessary for their accurate biological classification and diagnosis.

Thirteen-year long-term follow-up in a rare case of anaplastic astroblastoma: What makes the difference?

Background:

Astroblastomas are uncommon neuroepithelial tumors of the central nervous system with a distinct, yet, controversial radiological, histological, and molecular profile. Debatable differences between low- and high-grade astroblastoma have been reported in the medical literature; indeed, despite the increasing relevance of molecular genetic profiling in the realm of astroblastoma, its application is still in its early stages. As a result, the diagnostic criteria for astroblastoma remain undecided with yet no real consensus on the most ideal management.

Case Description:

This report describes a case of astroblastoma diagnosed 13 years ago in a young woman who despite six episodes of recurrence, transformation, and progression was able to retain a perfomace status of 0 by World Health Organization standard, throughout.

Conclusion:

This report discusses the clinical, radiological, histological features, and management of this rare tumor with an extraordinarily long survival, with an aim to strengthen the literature on management options. To the best of our knowledge, this is the longest surviving case of anaplastic astroblastoma reported in the available medical literature.

Clinicoradiological and histopathological characteristics and treatment outcomes of cerebral astroblastoma in children: a single-institution experience

OBJECTIVE

Astroblastoma (AB) is a rare glial tumor. The optimal treatment and prognosis of this tumor remain unclear. The authors retrospectively analyzed the clinical characteristics, neuroimaging findings, histopathological results, and treatment outcomes of 7 patients with AB.

METHODS

The study comprised 7 patients with pathologically proven AB who were surgically treated at Samsung Medical Center from November 1994 to January 2019. Clinicoradiological, histopathological, and surgical records were reviewed.

RESULTS

The patients included 5 girls (71.4%) and 2 boys (28.6%), with a median age of 13 years. All patients showed contrast enhancement on preoperative MRI: 5 ABs (71.4%) showed a concomitant solid and cystic appearance, and 2 (28.6%) demonstrated a solid appearance. ABs in 6 patients (85.7%) showed a well-circumscribed, characteristic "bubbly" appearance on T2-weighted MRI. Gross-total resection (GTR) was achieved in all cases (100%). Six patients (85.7%) were diagnosed with high-grade AB and 1 (14.3%) with low-grade AB. Six (85.7%) of the 7 patients received adjuvant treatment after resection, including 5 (83.3%) with AB who received chemotherapy and radiotherapy and 1 (16.7%) who received proton therapy alone. The median clinical follow-up duration was 96 months (range 48-189 months). Two patients experienced recurrence, and all patients in this series were alive at the last follow-up.

CONCLUSIONS

In this study, the clinicoradiological and histopathological features of AB were described. Based on the authors' limited experience with 7 cases, resection with the goal of GTR is currently the mainstream treatment for AB, and adjuvant radiation treatment should be considered after surgery.

Neuroimaging of astroblastomas: A case series and systematic review

BACKGROUND AND PURPOSE

Astroblastoma is a rare type of glial tumor, histologically classified into two types with different prognoses: high and low grade. We aimed to investigate the CT and MRI findings of astroblastomas by collecting studies with analyzable neuroimaging data and extracting the imaging features useful for tumor grading.

METHODS

We searched for reports of pathologically proven astroblastomas with analyzable neuroimaging data using PubMed, Scopus, and Embase. Sixty-five studies with 71 patients with astroblastomas met the criteria for a systematic review. We added eight patients from our hospital, resulting in a final study cohort of 79 patients. The proportion of high-grade tumors was compared in groups based on the morphology (typical and atypical) using Fisher's exact test.

RESULTS

High- and low-grade tumors were 35/71 (49.3%) and 36/71 (50.7%), respectively. There was a significant difference in the proportion of high-grade tumors based on the tumor morphology (typical morphology: high-grade = 33/58 [56.9%] vs. atypical morphology, 2/13 [15.4%], p = .012). The reviews of neuroimaging findings were performed using the images included in each article. The articles had missing data due to the heterogeneity of the collected studies.

CONCLUSIONS

Detailed neuroimaging features were clarified, including tumor location, margin status, morphology, CT attenuation, MRI signal intensity, and contrast enhancement pattern. The classification of tumor morphology may help predict the tumor's histological grade, contributing to clinical care and future oncologic research.

High-Grade Intraventricular Astroblastoma in a Young Adult: A Rare and Controversial Tumor to Manage

Astroblastoma is a rare primary central nervous system tumor of controversial site of origin. They account for 0.45-2.8% of all primary neuroepithelial central nervous system. It has been reported in paediatric age group with bimodal age distribution affecting more females with male to female ratio being 1:11. Astroblastomas are controversial and challenging tumors in terms of diagnosis and therapeutics. Since it carries an unpredictable disease course it needs a regular follow up even for low grade tumor. Authors have tried various schedules of post op radiotherapy after maximum safe resection. Various chemotherapeutic drugs combination have also been tried without much success. We here report a 35 years old female patient who was diagnosed with high grade astroblastoma referred for post-operative radiotherapy after gross total resection. Since it is extremely rare tumor, its treatment still not well defined and also makes it difficult conduct studies to examine tumor characteristics.

Cerebral Astroblastoma: A Rare Tumor

Astroblastoma is a rare neuroepithelial tumor of the central nervous system, which accounts for only 0.45-2.8% of all neuroglial tumors. These tumors have distinct radiological, histopathological, immunohistochemical, and molecular features. We describe a case of astroblastoma of the left temporal lobe in a 38-year-old female, who presented with complaints of headache and occasional episodes of vomiting.

A Rare Case of a High-Grade Astroblastoma with 5-Year Follow-up

Astroblastoma is a very rare glial tumor derived from astroblasts. It has been controversial in terms of its features and diagnosis. The objective of this report is to present the findings of the high-grade astroblastoma with a good prognosis in a 21-year-old female who presented to us with diplopia and headache. While imaging led to the foremost differentials of pleomorphic xanthoastrocytoma and Ganglioglioma which are low-grade neoplasms, the final diagnosis was established on microscopy and immunohistochemistry after excision. Treatment protocol included surgery with postoperative radiotherapy and chemotherapy. Due to controversial and limited literature, this tumor poses difficulties in diagnosis and management. This is a rare, successfully managed case of astroblastoma with a positive outcome 5 years after the diagnosis was established. In this case report, we review the steps of diagnosis, the differentials, the pathological and histological features, and the management of this rare entity.

A rare case of paediatric astroblastoma with concomitant MN1-GTSE1 and EWSR1-PATZ1 gene fusions altering management

In a case of astroblastoma, methylation analysis was uninformative, with no clustering with known CNS-HGNET-MN1 cases. Whole genome sequencing however identified a novel MN1-GTSE1 gene fusion (image), confirming the diagnosis of astroblastoma, as well as an EWSR1-PATZ1 gene fusion. Whole genome sequencing, alongside methylation profiling and conventional neuropathology, will continue to lead to improved diagnostics and prognostication for children with brain tumours.

Clinical characteristics, treatment and prognosis of angiocentric glioma

Angiocentric glioma (AG) is a rare subtype of neuroepithelial tumor in children and young adults that commonly presents with seizures. To study the clinical characteristics, treatment and prognosis of patients with AG, the features of two cases of AG were described and 108 cases reported in the literature were assessed. The cases of the present study were two males aged 8 and 16 years, who mainly presented with seizures. MRI revealed superficial, non-enhanced lesions in the left temporal and right frontal lobe, respectively. The two patients underwent gross total resection (GTR) and remained seizure-free without neurological deficits after 3.5 and 2.5 years, respectively. Histopathological examination revealed that the tumors consisted of monomorphous cells that surrounded the blood vessels and neurons in the cerebral cortex, and formed concentric sleeves or pseudorosettes. Furthermore, immunostaining indicated that the diffuse infiltrative neoplastic cells were positive for glial fibrillary acidic protein and a dot-like pattern of epithelial membrane antigen was observed. AG mostly appeared similar to low-grade gliomas on MRI. GTR of the lesions was curative and radiation or chemotherapy were not required. AG typically has a favorable prognosis, with low mortality and incidence of disability.

Posterior fossa astroblastoma in a child: a case report and a review of the literature

A 4-year-old girl presented to the hospital with a progressive headache, difficulty walking, and persistent daily vomiting for 3 weeks. Papilledema was observed on fundoscopic examination. A large left cerebellovermian tumor with "bubbly" appearance was discovered. Total removal of the tumor mass was performed, and a diagnosis of low-grade astroblastoma was made. Adjuvant radiotherapy was performed due to the risk of recurrence. The patient is disease-free and has been kept on close follow-up for 6 months. The occurrence of posterior fossa astroblastoma has been rarely reported in the literature. Thus, when a "bubby" appearance enhancing cystic solid tumor is located on the cerebellar hemisphere in a child, an astroblastoma should also be included in the differential diagnosis.

A case report of high-grade astroblastoma in a young adult

Astroblastoma is an uncommon neuroepithelial primary tumor of the brain which is of uncertain origin. We present a case of high-grade astroblastoma in an 18-year-old female with a severe headache, loss of appetite, vomiting and generalized weakness. The patient had undergone a right frontoparietal craniotomy. Large subfalcine meningioma was excised. The lesion was suspected to be a meningioma. Primary radiological investigation revealed a 6.8 cm × 5.8 cm × 5.4 cm lesion. Although the radiological and intraoperative findings were of an extra-axial tumor, the histology and immunophenotype was of an astroblastoma. The patient was treated with cyclophosphamide, cisplatin and etoposide chemotherapy regimen. The patient was later treated with bi-weekly bevacizumab. The patient had improved symptomatically post-chemotherapy. However, there was no significant difference in lesion size. The patient died after 2 weeks. The prognosis of patients with astroblastoma is extremely poor as observed in our case.