Epilepsy surgery related to pediatric brain tumors: Miami Children's Hospital experience.
OBJECTIVE
Pediatric brain tumors may be associated with medically intractable epilepsy for which surgery is indicated. The authors sought to evaluate the efficacy of epilepsy surgery for seizure control in pediatric patients with brain tumors.


METHODS
The authors performed a retrospective review of consecutive patients undergoing resective epilepsy surgery related to pediatric brain tumors at Miami Children's Hospital between June 1986 and June 2014. Time-to-event analysis for seizure recurrence was performed; an "event" was defined as any seizures that occurred following resective epilepsy surgery, not including seizures and auras in the 1st postoperative week. The authors analyzed several preoperative variables to determine their suitability to predict seizure recurrence following surgery.


RESULTS
Eighty-four patients (47 males) with a mean age (± standard deviation) of 8.7 ± 5.5 years (range 0.5-21.6 years) were included. The study included 39 (46%) patients with gliomas, 20 (24%) with dysembryoplastic neuroepithelial tumors (DNETs), 14 (17%) with gangliogliomas, and 11 (13%) with other etiologies. Among the patients with gliomas, 18 were classified with low-grade glioma, 5 had oligodendroglioma, 6 had uncategorized astrocytoma, 3 had pilocytic astrocytoma, 3 had pleomorphic xanthoastrocytoma, 3 had glioblastoma, and 1 had gliomatosis cerebri. Seventy-nine (94.0%) resections were guided by intraoperative electrocorticography (ECoG). The mean time (± standard deviation) to seizure recurrence was 81.8 ± 6.3 months. Engel Class I outcome was achieved in 66 (78%) and 63 (75%) patients at 1 and 2 years' follow-up, respectively. Patients with ganglioglioma demonstrated the highest probability of long-term seizure freedom, followed by patients with DNETs and gliomas. In univariate analyses, temporal location (HR 1.75, 95% CI 0.26-1.27, p = 0.171) and completeness of resection (HR 1.69, 95% CI 0.77-3.74, p = 0.191) demonstrated a trend toward a longer duration of seizure freedom.


CONCLUSIONS
ECoG-guided epilepsy surgery for pediatric patients with brain tumors is highly effective. Tumors located in the temporal lobe and those in which a complete ECoG-guided resection is performed may result in a greater likelihood of long-term seizure freedom.
Departments of 1 Neurosurgery and.|Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario, Canada.
Aria
A
Fallah
Departments of 1 Neurosurgery and.
Alexander G
AG
Weil
Departments of 1 Neurosurgery and.
Samir
S
Sur
Neurology, Miami Children's Hospital, Miami, Florida; and.
Ian
I
Miller
Departments of 1 Neurosurgery and.
Prasanna
P
Jayakar
Departments of 1 Neurosurgery and.
Glenn
G
Morrison
Departments of 1 Neurosurgery and.
Sanjiv
S
Bhatia
Departments of 1 Neurosurgery and.
John
J
Ragheb
D000293:Adolescent; D001254:Astrocytoma / Q000601:surgery; D001932:Brain Neoplasms / Q000150:complications / Q000473:pathology / Q000601:surgery*; D002648:Child; D002675:Child, Preschool; D004569:Electroencephalography; D004827:Epilepsy / Q000209:etiology / Q000601:surgery*; D005260:Female; D005431:Florida; D005500:Follow-Up Studies; D018303:Ganglioglioma / Q000601:surgery; D005909:Glioblastoma / Q000601:surgery; D005910:Glioma / Q000150:complications / Q000601:surgery*; D006801:Humans; D007223:Infant; D053208:Kaplan-Meier Estimate; D008297:Male; D018302:Neoplasms, Neuroepithelial / Q000601:surgery; D019635:Neurosurgical Procedures / Q000379:methods*; D011237:Predictive Value of Tests; D012008:Recurrence; D012189:Retrospective Studies; D012307:Risk Factors; D012720:Severity of Illness Index; D013702:Temporal Lobe / Q000473:pathology* / Q000503:physiopathology / Q000601:surgery; D013997:Time Factors; D016896:Treatment Outcome; D055815:Young Adult
AED = antiepileptic drug; DNET = dysembryoplastic neuroepithelial tumor; ECoG = electrocorticography; EEG = electroencephalography; ETANTR = embryonal tumor with abundant neuropil and true rosettes; EZ = epileptogenic zone; FCD = focal cortical dysplasia; LGG = low-grade glioma; TTE = time to event; oncology; pediatric brain tumor; resective epilepsy surgery; seizure freedom; time to event