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Angiocentric glioma — Clinical Guidelines

Overview

Angiocentric glioma (AG) is a rare, low-grade central nervous system (CNS) neoplasm characterized by its distinctive angiocentric pattern, where neoplastic cells predominantly surround blood vessels. It predominantly affects pediatric and adolescent populations, presenting clinically with seizures, often medically intractable. Despite its infiltrative nature, AG is generally considered indolent with a favorable prognosis when managed surgically. Understanding AG is crucial for clinicians due to its unique histopathological features and the need for accurate diagnosis to avoid inappropriate aggressive treatments 1 3 5.

Pathophysiology

Angiocentric glioma arises from progenitor cells with dual astrocytic and ependymal differentiation, leading to a distinctive histological appearance where tumor cells are elongated and bipolar, aligning closely around blood vessels. This arrangement mimics radial glia and tanycytes, contributing to its infiltrative yet typically slow-growing behavior. Molecularly, AG often lacks common genetic alterations seen in other gliomas, such as IDH mutations and 1p/19q codeletions, though some cases may exhibit wild-type status for these markers 5 6. The exact molecular drivers of AG remain under investigation, with ongoing research focusing on potential microenvironmental influences and rare instances of atypical behavior, such as increased proliferative indices or metastatic spread 2 6.

Epidemiology

Angiocentric glioma is exceedingly rare, with fewer than 100 cases reported in the literature as of recent reviews. It predominantly affects children and young adults, with a mean age at diagnosis around 15 years, showing no significant gender predilection. Geographic distribution data are limited, but cases have been reported globally, suggesting no specific regional clustering. Incidence figures are not well-defined due to the rarity of the condition, but trends indicate a consistent pattern of sporadic occurrence without clear temporal increases 1 3 7.

Clinical Presentation

Patients with angiocentric glioma typically present with seizures, often refractory to initial anticonvulsant therapy, reflecting the tumor's common location in cortical regions. Additional symptoms can include focal neurological deficits, headaches, and, rarely, raised intracranial pressure. Atypical presentations, such as spinal metastases (though exceedingly rare), can complicate diagnosis and necessitate thorough imaging and histopathological confirmation 2 3 7.

Diagnosis

Diagnosis of angiocentric glioma relies heavily on histopathological examination, given its distinctive perivascular arrangement of cells. Key diagnostic criteria include:

Histopathological Features: Elongated, bipolar cells arranged around blood vessels, forming pseudorosettes, and often with a mucoid matrix or microcalcifications.

Immunohistochemistry: Positive for GFAP and S-100, with occasional EMA positivity.

Imaging: MRI typically shows a well-demarcated, non-enhancing cortical mass with possible cortical thickening or subpial spread.

Differential Diagnosis:

- Cortical Ependymoma: Distinguished by more pronounced perivascular pseudorosettes and absence of astrocytic features. - Astroblastoma: Characterized by a more solid, less vascular pattern and distinct nuclear features. - Pilomyxoid Astrocytoma: Features a myxoid matrix and more pronounced fibrillary astrocytic differentiation. - Low-grade Astrocytoma: Lacks the characteristic angiocentric pattern and may show more cellularity and nuclear atypia 1 3 5 8.

Management

Surgical Excision

Primary Approach: Gross-total resection (GTR) is the mainstay of treatment, aiming to achieve maximal tumor removal to alleviate symptoms and prevent recurrence.

Indications: Recommended for all symptomatic patients with accessible lesions.

Outcome Monitoring: Postoperative seizure control assessment and regular MRI follow-up to monitor for recurrence.

Adjuvant Therapy

Radiotherapy: Reserved for cases with incomplete resection or high-risk features, though evidence is limited and generally not routinely recommended 1 3.

Chemotherapy: Not typically indicated due to the low-grade nature of AG, except in refractory cases where further investigation is warranted 5.

Seizure Management

Initial Therapy: Initiate with first-line antiepileptic drugs (AEDs) such as levetiracetam, valproate, or lamotrigine.

Refractory Cases: Consider second-line AEDs like topiramate or rufinamide, with referral to a neurologist for advanced management strategies.

Complications

Seizure Persistence: Continued seizures despite surgical intervention may require long-term AED therapy.

Recurrent Disease: Rare but possible, necessitating close follow-up with MRI scans every 6-12 months post-surgery.

Metastatic Spread: Extremely rare, but documented cases highlight the need for vigilance in atypical presentations, particularly spinal metastases 2.

Prognosis & Follow-up

The prognosis for angiocentric glioma is generally favorable, with most patients achieving long-term remission following surgical excision. Key prognostic indicators include extent of resection and absence of recurrence. Recommended follow-up includes:

Imaging: MRI every 6-12 months for the first few years post-surgery.

Neurological Assessments: Regular clinical evaluations to monitor for new neurological deficits or seizure recurrence.

Seizure Control: Periodic reassessment of AED efficacy and side effects.

Special Populations

Pediatric Patients: Management focuses heavily on minimizing AED side effects and ensuring developmental support post-surgery.

Adults: Less common but requires similar surgical approaches; long-term seizure management may be more complex due to comorbid conditions.

Refractory Cases: Tailored multidisciplinary approaches, including neurology and neurosurgery consultations, are essential for optimal outcomes 5 8.

Key Recommendations

Surgical Resection: Gross-total resection should be pursued for symptomatic angiocentric glioma to optimize seizure control and prevent recurrence (Evidence: Strong 1 3).

Histopathological Confirmation: Definitive diagnosis relies on characteristic histopathological features and immunohistochemical markers (Evidence: Strong 3 5).

Seizure Management: Initiate with first-line antiepileptic drugs and escalate based on response; consider neurology consultation for refractory cases (Evidence: Moderate 1 3).

Regular Follow-up: Schedule MRI scans every 6-12 months post-surgery and conduct regular neurological assessments (Evidence: Moderate 1 3).

Avoid Unnecessary Aggressive Therapy: Limit adjuvant radiotherapy and chemotherapy to exceptional cases due to the generally indolent nature of AG (Evidence: Moderate 1 5).

Monitor for Recurrence: Vigilantly monitor for signs of recurrence, especially in cases with incomplete resection (Evidence: Moderate 1 7).

Consider Multidisciplinary Care: For refractory cases or atypical presentations, involve neurology and neurosurgery teams for comprehensive management (Evidence: Expert opinion 8).

Long-term AED Management: Tailor antiepileptic drug regimens to minimize side effects and optimize seizure control in pediatric and adult patients (Evidence: Moderate 5).

Evaluate for Metastatic Spread: In cases with atypical presentations or neurological decline, consider imaging of the spine to rule out rare metastatic disease (Evidence: Weak 2).

Genetic and Molecular Testing: While not routinely indicated, consider molecular profiling in atypical cases to rule out other glioma subtypes (Evidence: Expert opinion 5).

References

1 Zuo P, Jiang K, Zou W, Li H, Wang Y. Angiocentric glioma: a single center experience and literature review. Child's nervous system : ChNS : official journal of the International Society for Pediatric Neurosurgery 2025. link 2 O'Halloran PJ, Amoo M, Dablouk MO, Beausang A, MacNally S. Angiocentric glioma: Drop Metastases to the Spinal Cord. World neurosurgery 2020. link 3 Gupta S, Rangari KV, Mehrotra A, Pal L, Jaisawal AK, Kumar R. Temporal lobe angiocentric glioma with oligodendroglioma-like areas: a rare association of an uncommon tumor. A case report with review of literature. Child's nervous system : ChNS : official journal of the International Society for Pediatric Neurosurgery 2020. link 4 Whitehead MT, Vezina G. MR Spectroscopic Profile of an Angiocentric Glioma. Anticancer research 2015. link 5 Buccoliero AM, Castiglione F, Degl'innocenti DR, Moncini D, Spacca B, Giordano F et al.. Angiocentric glioma: clinical, morphological, immunohistochemical and molecular features in three pediatric cases. Clinical neuropathology 2013. link 6 Pokharel S, Parker JR, Parker JC, Coventry S, Stevenson CB, Moeller KK. Angiocentric glioma with high proliferative index: case report and review of the literature. Annals of clinical and laboratory science 2011. link 7 Hu XW, Zhang YH, Wang JJ, Jiang XF, Liu JM, Yang PF. Angiocentric glioma with rich blood supply. Journal of clinical neuroscience : official journal of the Neurosurgical Society of Australasia 2010. link 8 Mott RT, Ellis TL, Geisinger KR. Angiocentric glioma: a case report and review of the literature. Diagnostic cytopathology 2010. link

Angiocentric glioma