Dysembryoplastic neuroepithelial tumor

[edit] Discussion of Dysembryoplastic neuroepithelial tumor

Dysembryoplastic neuroepithelial tumor (DNET) is a benign tumor arising from the cortical or deep gray matter.
These tumors almost always manifest in patients with medically refractory partial seizures.
Majority of patients are younger than 20 years
Males are more commonly affected.
The temporal lobe is the most common site (62%) followed by the frontal lobe (31%).
Dysembryoplastic neuroepithelial tumors are remarkably stable in terms of biologic behavior.
- Despite only partial resection, complete cessation of all seizure activity is a common.
- Recurrence is also very rare.

Imaging characteristics of dysembryoplastic neuroepithelial tumor is similar to those of other low-grade glial tumors and may not be possible to distinguish this tumor from diffuse astrocytoma, ganglioglioma, oligodendroglioma, or other low-grade neoplasms.

At CT, the tumor manifests as a hypoattenuating mass.
Calcification may be seen.
Remodeling of the adjacent inner table of the skull may also be seen.
At MR imaging, dysembryoplastic neuroepithelial tumors most commonly manifest as cortical masses that are hypointense on T1-weighted images and hyperintense on T2-weighted images without surrounding vasogenic edema.
Some lesions may appear as an enlarged gyrus, producing a soap bubble appearance at the cortical margin.
Approximately one-third of dysembryoplastic neuroepithelial tumors enhance following intravenous administration of contrast material.

Patient #1