Corpus callosum (butterfly glioma)

What it is

The corpus callosum is the large band of nerve fibers connecting the left and right cerebral hemispheres, allowing them to communicate. A glioma that spreads across the corpus callosum into both hemispheres can form a symmetric "butterfly" shape on imaging, a sign of aggressive infiltration.

Understanding Corpus callosum (butterfly glioma)

The corpus callosum is the main white matter bridge between the two halves of the brain. Because diffuse gliomas spread along white matter pathways, an aggressive glioma can extend through the corpus callosum to involve both hemispheres — producing a butterfly-shaped appearance on MRI. This "butterfly glioma" pattern is most often seen with glioblastoma and indicates extensive, aggressive infiltration that crosses the midline. Such tumors are particularly difficult to treat surgically, because removing tumor from both hemispheres while preserving function is very challenging, so treatment often emphasizes biopsy for diagnosis followed by radiation and chemotherapy. Understanding the butterfly glioma clarifies how gliomas can spread across the brain's central bridge and why this pattern signals an aggressive tumor. The specific diagnosis still guides treatment. Understanding this pattern clarifies a sign of aggressive spread.

Why it matters

Understanding the butterfly glioma helps patients and families see how an aggressive glioma can spread across the brain's central bridge to both hemispheres — a pattern that signals extensive infiltration and shapes treatment.