Thalamic gliomas in children: an extensive clinical, neuroradiological and pathological study of 14 cases

Abstract

Object: Thalamic tumors represent only 1 to 5% of brain neoplasms but frequently affect children. However, pediatric series are rare and go back to several years in spite of recent advances in the neuroradiological, pathological, and molecular fields.

Methods: We report a series of 14 pediatric thalamic gliomas with clinical, neuroradiological, and pathological studies including p53 immunostaining in 11 cases and 1p19q status in three cases.

Results: Our series included five pilocytic astrocytomas, seven oligodendrogliomas, and two glioblastomas. Pilocytic astrocytomas were characterized by strong contrast enhancement, lack of p53 expression, and excellent prognosis. Oligodendrogliomas frequently demonstrated an aspect of unilateral thalamic enlargement lacking or with slight contrast enhancement. Some of them expressed p53 or demonstrated 1p loss. Anaplastic oligodendrogliomas and glioblastomas displayed a poor outcome, with a mean survival of 8 months after surgery.

Conclusion: Our series of pediatric thalamic gliomas clearly distinguishes pilocytic astrocytomas from anaplastic oligodendrogliomas regarding neuroimaging, pathology, and prognosis.