title: Atypical pediatric ganglioglioma is common and associated with a less favorable clinical course.
abstract: OBJECT Ganglioglioma (GG) is commonly recognized as a low-grade tumor located in the temporal lobe, often presenting with seizures. Most are amenable to complete resection and are associated with excellent oncological outcome. The authors encountered several GGs in various locations, which seem to have a less favorable clinical course than GGs in the temporal lobe. METHODS The authors performed a single-center retrospective review of all children with a histological diagnosis of GG who were treated at Children's Hospital Colorado between 1997 and 2013. Each tumor was categorized by 2 pediatric neuroradiologists as typical or atypical based on preoperative MRI appearance. Typical lesions were cortically based, within a single cerebral lobe, well-circumscribed, and solid or mixed solid/cystic. The treatment and clinical course of each patient was analyzed. RESULTS Thirty-seven children were identified, with a median age at presentation of 8.2 years and median follow-up of 38.0 months. Eighteen tumors (48.6%) were typical and 19 (51.4%) were atypical. All typical lesions presented with seizures, whereas no atypical lesions did so. Sixteen (88.9%) typical lesions were located in the temporal lobe. In the atypical group, tumor location was variable, including 11 (57.9%) in the brainstem. Death during follow-up was statistically more common in the atypical group (31.6% vs 0%, p = 0.02). Gross-total resection (GTR) was achieved for 15 of 16 typical tumors (93.8%), compared with 3 atypical tumors (15.8%, p < 0.0001). Presentation with seizure or non-brainstem location were each associated with survival (p = 0.02 and 0.004, respectively). The presence of mutation in BRAF exon 15 did not differ between the 2 groups. CONCLUSIONS Pediatric GG with typical imaging features is associated with excellent rates of GTR and overall survival. Atypical GG is commonly encountered, less amenable to GTR, and associated with a worse outcome. This may relate to anatomical or biological characteristics and merits further investigation.
authors.affiliation: Pediatric Neurosurgery;
authors.forename: Mohana Rao
authors.initials: MR
authors.lastname: Patibandla
authors.affiliation: Pediatric Neurosurgery;
authors.forename: Thomas
authors.initials: T
authors.lastname: Ridder
authors.affiliation: Division of Neuro-oncology, Department of Pediatrics; and 
authors.forename: Kathleen
authors.initials: K
authors.lastname: Dorris
authors.affiliation: Adult and Child Center for Health Outcomes Research and Delivery Science, University of Colorado Anschutz Medical Campus, Aurora, Colorado.
authors.forename: Michelle R
authors.initials: MR
authors.lastname: Torok
authors.affiliation: Departments of 4 Radiation Oncology and.
authors.forename: Arthur K
authors.initials: AK
authors.lastname: Liu
authors.affiliation: Pediatric Neurosurgery;
authors.forename: Michael H
authors.initials: MH
authors.lastname: Handler
authors.affiliation: Radiology, Children's Hospital Colorado, University of Colorado Anschutz Medical Campus; and.
authors.forename: Nicholas V
authors.initials: NV
authors.lastname: Stence
authors.affiliation: Radiology, Children's Hospital Colorado, University of Colorado Anschutz Medical Campus; and.
authors.forename: Laura Z
authors.initials: LZ
authors.lastname: Fenton
authors.affiliation: Pediatric Neurosurgery;|Adult and Child Center for Health Outcomes Research and Delivery Science, University of Colorado Anschutz Medical Campus, Aurora, Colorado.
authors.forename: Todd C
authors.initials: TC
authors.lastname: Hankinson
mesh_terms: D000293:Adolescent; D000328:Adult; D020295:Brain Stem Neoplasms / Q000401:mortality / Q000473:pathology / Q000601:surgery; D002648:Child; D002675:Child, Preschool; D005260:Female; D005500:Follow-Up Studies; D018303:Ganglioglioma / Q000145:classification / Q000401:mortality / Q000473:pathology / Q000601:surgery; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D017063:Outcome Assessment, Health Care / Q000706:statistics & numerical data*; D012189:Retrospective Studies; D015173:Supratentorial Neoplasms / Q000401:mortality / Q000473:pathology / Q000601:surgery; D013702:Temporal Lobe / Q000473:pathology / Q000601:surgery; D055815:Young Adult
keywords: AT/RT = atypical teratoid/rhabdoid tumor; GG = ganglioglioma; GTR = gross-total resection; STR = subtotal resection; atypical ganglioglioma; brain tumor; ganglioglioma; oncology; pediatric brain tumor