Subependymal Spread
Tumor extension along the subependymal layer beneath the ventricular lining, characteristic of certain gliomas.
Full Definition
Subependymal spread refers to tumor extension along the subependymal layer, which lies immediately beneath the ependymal lining of the ventricular system. This pattern of growth is particularly characteristic of certain gliomas and represents a pathway for tumor dissemination within the brain. The subependymal space provides a relatively resistance-free plane for tumor cells to migrate, potentially leading to multifocal disease. On magnetic resonance imaging, subependymal spread appears as enhancement or signal abnormality along ventricular margins. In treatment planning, recognition of this pattern is crucial as it may influence the extent of radiation fields and surgical approaches. The finding also has prognostic implications and may indicate more aggressive tumor behavior.
Usage
Usage note: Important pattern affecting treatment planning; indicates potential for multifocal disease.
In Context
- "Post-contrast imaging demonstrated subependymal spread along the lateral ventricular margins." — MRI report
- "The radiation treatment volume was expanded to encompass areas of subependymal spread." — Radiation planning note