Newly Recognized CNS Tumors in the 2021 World Health Organization Classification: Imaging Overview with...

Area of Science:

• Neuropathology
• Neuroradiology
• Oncology

Background:

• The World Health Organization (WHO) updated its classification of central nervous system (CNS) tumors in 2021.
• This revision incorporates advances in understanding tumor genetics, pathogenesis, and therapeutic targets.
• Genetic alterations are increasingly crucial for CNS tumor classification, prognosis, and treatment.

Purpose of the Study:

• To review the 22 newly recognized CNS tumor entities introduced in the 2021 WHO classification.
• To correlate the imaging appearance of these new entities with their histologic and genetic characteristics.
• To provide a resource for clinicians and researchers on these emerging tumor types.

Main Methods:

• Review of the 2021 WHO classification of CNS tumors.
• Compilation of imaging findings for the 22 newly described entities.
• Correlation of imaging features with available histopathologic and molecular genetic data.

Main Results:

• Detailed description of the imaging phenotypes of 22 newly classified CNS tumors.
• Emphasis on key distinguishing features, including location, enhancement patterns, and associated findings.
• Integration of genetic information (e.g., mutations, fusions) with imaging and histology.

Conclusions:

• The 2021 WHO classification significantly expands the spectrum of recognized CNS tumors.
• Understanding the integrated clinicopathologic and genetic features, including imaging, is essential for accurate diagnosis.
• Radiologists and pathologists must be familiar with these new entities for optimal patient management.