IMPORTANT: We currently have a number of bugs related to image cropping and are actively trying to resolve them. In the meantime, we have disabled cropping. Apologies for any inconvenience. Stay informed: radiopaedia.org/chat

Oligodendroglioma (grade 3)

Case contributed by Frank Gaillard
Diagnosis certain

Presentation

Seizure

Patient Data

Age: 60 years
mri

A large right frontal mass with calcification and enhancement is present. Large portions of the mass involve the cortex. Features are those of an oligodendroglial tumor. 

ct

The right-sided mass is heavily calcified with some patchy areas on enhancement seen at the margins. 

Case Discussion

The patient went on to have surgery confirming the diagnosis of an anaplastic oligodendroglioma. It is important to note that since 2016 the WHO classification of CNS tumors, a tumor that has been shown to be an oligodendroglioma (IDH mutant, 1p19q co-deleted) the presence of necrosis and microvascular proliferation does not change the diagnosis to GBM. The most an oligodendroglioma can ever aspire to become anaplastic. 

Histology

MICROSCOPIC DESCRIPTION: Sections show a moderately cellular tumor composed of moderately pleomorphic cells containing round to oval, hyperchromatic, vesicular nuclei with inconspicuous nucleoli and prominent perinuclear clearing. Tumor cells are arranged in diffuse sheets intersected by thin-walled "chicken-wire" capillaries. Prominent microcalcification is present. Occasional mitotic figures are identified (up to 2/10hpf). Focal pallisaded tumor necrosis and microvascular proliferation are seen.

IMMUNOHISTOCHEMISTRY:

  • GFAP Negative
  • Nogo A Positive
  • Nestin Positive (low)
  • IDH-1 R132H Positive (mutated)
  • ATRX Positive (non-mutated)
  • MGMT Negative (likely methylated)
  • p53 Negative
  • p16 Positive
  • Topoisomerase labeling index: Approximately 8%.

FISH for chromosome 1p/19q co-deletion: 

  • 1p36 deletion detected
  • 19q13.3 deletion detected

Final diagnosis

Oligodendroglioma, IDH-mutant, and 1p/19q-codeleted WHO CNS grade 3

How to use cases

You can use Radiopaedia cases in a variety of ways to help you learn and teach.

Creating your own cases is easy.

Updating… Please wait.

 Unable to process the form. Check for errors and try again.

 Thank you for updating your details.