title: Thalamic high-grade gliomas in children: a distinct clinical subset?
abstract: Pediatric high-grade gliomas (HGGs) of the thalamic region account for up to 13% of pediatric HGGs and usually result in only anecdotal long-term survival. Because very little is known about these tumors, we aimed to further characterize them. In our series of 99 pediatric thalamic HGGs, there were no significant differences in survival between patients with tumors affecting the thalamus alone (including bithalamic lesions) and patients with tumors affecting the thalamus plus adjacent structures. Tumor resection (event-free survival/overall survival) and an early treatment response to radiotherapy/chemotherapy (event-free survival) had independent prognostic significance, as shown by Kaplan-Meier and multivariate Cox regression analyses. When we compared clinical characteristics and outcomes of pediatric thalamic HGG with those of pediatric (nonthalamic) supratentorial (n = 177) as well as pediatric pontine HGG (including diffuse intrinsic pontine gliomas; n = 234), we found that thalamic HGG shared more similarities with pontine than with supratentorial HGG, but overall, it appeared to represent a clinically distinct subgroup of pediatric HGG. The varying extent of tumor resection in the different tumor localizations may play some role in the observed clinical differences, as shown by multivariate Cox regression analyses, but the tumor site itself was also identified as an independent prognostic parameter. Thus, an additional location-specific effect on survival and/or tumor biology, despite different neurosurgical accessibility, has to be considered. Therefore, future investigations should try to further characterize the obviously site-specific heterogeneity of pediatric HGG on a molecular genetic basis.
authors.affiliation: University Children's Hospital, Martin-Luther-University Halle-Wittenberg, Ernst-Grube-Str. 40, 06120 Halle, Germany. christof.kramm@uk-halle.de
authors.forename: Christof M
authors.initials: CM
authors.lastname: Kramm
authors.forename: Sandra
authors.initials: S
authors.lastname: Butenhoff
authors.forename: Ulrike
authors.initials: U
authors.lastname: Rausche
authors.forename: Monika
authors.initials: M
authors.lastname: Warmuth-Metz
authors.forename: Rolf-Dieter
authors.initials: RD
authors.lastname: Kortmann
authors.forename: Torsten
authors.initials: T
authors.lastname: Pietsch
authors.forename: Astrid
authors.initials: A
authors.lastname: Gnekow
authors.forename: Norbert
authors.initials: N
authors.lastname: Jorch
authors.forename: Gisela
authors.initials: G
authors.lastname: Janssen
authors.forename: Frank
authors.initials: F
authors.lastname: Berthold
authors.forename: Johannes E
authors.initials: JE
authors.lastname: Wolff
mesh_terms: D000293:Adolescent; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D001932:Brain Neoplasms / Q000145:classification* / Q000473:pathology* / Q000628:therapy; D002648:Child; D002675:Child, Preschool; D003131:Combined Modality Therapy; D005260:Female; D005500:Follow-Up Studies; D005910:Glioma / Q000145:classification* / Q000556:secondary* / Q000628:therapy; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D009367:Neoplasm Staging; D011878:Radiotherapy; D015996:Survival Rate; D013788:Thalamus / Q000473:pathology*; D016896:Treatment Outcome