Radiological Characteristics and Natural History of Adult IDH-Wildtype Astrocytomas with TERT Promoter Mutations

Neurosurgery. 2019 Sep 1;85(3):E448-E456. doi: 10.1093/neuros/nyy513.

Abstract

Background: Adult IDH-wildtype astrocytomas with TERT promoter mutations (TERTp) are associated with a poor prognosis.

Objective: To analyze the radiological presentation and natural history of adult IDH-wildtype astrocytomas with TERTp.

Methods: We retrospectively reviewed the characteristics of 40 IDH-wildtype TERTp-mutant astrocytomas (grade II n = 19, grade III n = 21) and compared them to those of 114 IDH-mutant lower grade gliomas (LGG), of 92 IDH-wildtype TERTp-mutant glioblastomas, and of 15 IDH-wildtype TERTp-wildtype astrocytomas.

Results: Most cases of IDH-wildtype TERTp-mutant astrocytomas occurred in patients aged >50 yr (88%) and presented as infiltrative lesions without contrast enhancement (73%) that were localized in the temporal and/or insular lobes (37.5%) or corresponded to a gliomatosis cerebri (43%). Thalamic involvement (33%) and extension to the brainstem (27%) were frequently observed, as was gyriform infiltration (33%). This radiological presentation was different from that of IDH-mutant LGG, IDH-wildtype TERTp-mutant glioblastomas, and IDH-wildtype TERTp-wildtype astrocytomas. Tumor evolution before treatment initiation was assessable in 17 cases. Ten cases demonstrated a rapid growth characterized by the apparition of a ring-like contrast enhancement and/or a median velocity of diametric expansion (VDE) ≥8 mm/yr but 7 cases displayed a slow growth (VDE <8 mm/yr) that could last several years before anaplastic transformation. Median overall survival of IDH-wildtype TERTp-mutant astrocytomas was 27 mo.

Conclusion: IDH-wildtype TERTp-mutant astrocytomas typically present as nonenhancing temporo-insular infiltrative lesions or as gliomatosis cerebri in patients aged >50 yr. In the absence of treatment, although rapid tumor growth is frequent, an initial falsely reassuring, slow growth can be observed.

Keywords: IDH-wildtype astrocytoma; Lower grade gliomas; Telomerase reverse transcriptase promoter.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Brain Neoplasms / genetics*
  • Brain Neoplasms / pathology*
  • Disease Progression
  • Female
  • Glioma / genetics*
  • Glioma / pathology*
  • Humans
  • Isocitrate Dehydrogenase / genetics
  • Middle Aged
  • Mutation
  • Promoter Regions, Genetic
  • Retrospective Studies
  • Telomerase / genetics

Substances

  • Isocitrate Dehydrogenase
  • TERT protein, human
  • Telomerase