Our case series is composed of the first 3 patients surgically treated at our institution for angiocentric glioma, a newly established brain tumor type. Two of the patients, ages 10 and 13 years, presented with intractable seizures, and the other patient, 10 years old, presented with headaches and decreasing visual acuity. Magnetic resonance imaging studies with an added contrast agent showed focal, nonenhancing, T2-hyperintense lesions all located in the left temporal lobe. All 3 tumors were histologically defined by diffusely infiltrating monomorphous tumor cells with prominent perivascular clustering. Two of the 3 tumors were GFAP positive and contained characteristic EMA-positive microlumens. Surgical treatment of these focal tumors yielded excellent outcomes in all 3 patients, and for as long as a 24-month postoperative period in 1 patient. In cases of pharmacoresistant epilepsy, resection was 100% effective in seizure resolution.
Overall, our description of the clinicopathological features and outcomes of pediatric patients with angiocentric glioma is consistent with the few previously reported cases of this novel tumor type in children. The clinical findings in all reported pediatric cases of angiocentric glioma are summarized in . The age at surgery ranged from 2 to 14 years (median 6.5 years). Fourteen patients were male and 11 were female. Among the 25 documented pediatric cases of angiocentric glioma, 24 patients (96%) presented with intractable seizures. In all cases, the tumor was located supratentorially, with 10 in the frontal lobe, 8 in the temporal lobe, 6 in the parietal lobe, and 1 in the occipital lobe. Radiographic features exhibited in all cases included unifocality, T2 hyperintensity, and no enhancement with the addition of a contrast agent. Additionally, Lellouch-Tubiana et al.3
and Preusser et al.6
identified the cortical rim of hyperintensity on T1-weighted images (Cases 9–23) and the stalklike extension to the adjacent ventricle on T2-weighted images (Cases 9–18) as pathognomonic radiological features of angio-centric glioma. However, these characteristics were not seen on the MR images obtained in our patients. In 14 (56%) of the 25 cases in the literature, GTR of the tumor was achieved, and all patients remained seizure free without tumor recurrence. On the other hand, among the 9 cases (36%) with only STR of the tumor, 4 patients experienced a return of their seizures. One patient who underwent STR with radiation treatment as well as another patient who underwent a biopsy procedure and radiation therapy showed complete seizure resolution.
Literature review of studies on angiocentric gliomas*
Nearly all of the patients in our series, as well as those in the reviewed cases, presented with seizures. This finding suggests that angiocentric glioma—as well as focal cortical dysplasias and glioneuronal tumors such as gangliomas and dysembryoplastic neuroepithelial tumors—must be considered in the neurosurgical evaluation of medically refractory epilepsy in children and young adults.
Nonetheless, the presenting factors and outcome in cases of angiocentric gliomas are distinct among seizure-associated lesions in children. The median age at surgery for patients among the 25 cases was 6.5 years, compared with 9.9 years for children in the Göteborg epilepsy surgery series.2
The male/female ratio in our review was 14:11, versus 29:31 in the Göteborg series. The supratentorial distribution of angiocentric gliomas is varied, whereas epileptogenic foci are more commonly concentrated in the temporal lobe. Most patients with angiocentric gliomas (96%) present with seizures. Low-grade gliomas, however, accounted for only 8% of the histopathological diagnoses in the Swedish study and were associated with 66.7% seizure freedom by the 2-year follow-up. Postoperative seizure freedom in our review was 100% with GTR and 56% with STR at 2.3–168 months of follow-up.
Histopathologically, angiocentric glioma is firmly established as a unique entity, although its cytogenesis remains unclear. Whether from astrocytic and ependymal lineages, as posited by Wang et al.,8
or from radial glia or neuronal origins, as suggested by Lellouch-Tubiana et al.,3
this distinctive tumor has been commonly observed to behave as a low-grade neoplasm, thereby accounting for its excellent prognosis in all documented surgical cases. In fact, all cases involving GTR have resulted in seizure resolution and positive outcomes. Only in cases of STR has symptom recurrence been documented.
The recognition of angiocentric glioma, then, permits a diagnosis with a more favorable prognosis compared with other supratentorial gliomas characterized by seizures in children. Moreover, clinical analysis of the disease affirms that the extent of resection is likely the primary determinant of seizure-free survival in children with brain tumors.