Pediatric Thalamic Gliomas: An Updated Review.

Area of Science:

• Neuro-oncology
• Pediatric oncology
• Tumor pathology

Background:

• Thalamic neoplasms are rare overall but represent a significant portion of pediatric brain tumors.
• They constitute approximately 5% of pediatric intracranial tumors and up to 15% of malignant pediatric intracranial tumors in some studies.

Purpose of the Study:

• To provide an updated understanding of the diverse histology, biology, and behavior of pediatric thalamic tumors.
• To emphasize the critical role of histologic verification in treatment planning for these rare tumors.

Main Methods:

• A comprehensive PubMed search was conducted using keywords "pediatric + thalamic + glioma".
• Analysis included 445 cases of thalamic gliomas in patients under 18 years old from 45 publications.
• Data from 9 institutional series detailing various pediatric thalamic tumor histologies were reviewed.

Main Results:

• Astrocytomas constitute 81% of pediatric thalamic tumors, with diffuse astrocytomas being the most prevalent subtype.
• High-grade diffuse astrocytomas (World Health Organization grades III-IV) represent the largest single category of pediatric thalamic tumors.
• Oligodendrogliomas and ependymomas account for 10% and 3% of cases, respectively, often presenting as anaplastic.

Conclusions:

• Accurate tissue diagnosis is paramount for prognostication and guiding treatment strategies in pediatric thalamic tumors.
• The discovery of molecular targets further underscores the importance of precise histologic and molecular subtyping.
• Definitive diagnosis facilitates the identification of tumors amenable to surgical resection, improving patient outcomes.