Diffuse astrocytoma NOS ("protoplasmic")

Case contributed by Dr Jeremy Jones


Headaches and first seizure.

Patient Data

Age: 14 years
Gender: Male

Large tumor centered on the left middle frontal gyrus. It is T2 bright with areas of T2 hyperintensity that suppress on FLAIR.  Rim-like diffusion restriction and virtually no contrast enhancement.

Case Discussion

The patient went on to have surgery. 



Section show a moderately cellular tumor comprising astrocytes showing hyperchromatic nuclei, moderate nuclear pleomorphism and ill-defined eosinophilic cytoplasm.  

Mitotic activity is not seen.  Rosenthal fibers or eosinophilic granular bodies are not identified.  There is no necrosis or microvascular proliferation. A Ki-67 stain shows a proliferative index of approximately 10%. 

Features consistent with a low-grade glioma and most in keeping with a protoplasmic astrocytoma.


Until recently, protoplasmic astrocytomas were classified as a subtype low-grade astrocytoma, however, in the latest (2016) update to WHO classification of CNS tumors, protoplasmic astrocytomas no longer exists as a distinct entity. 

Note: IDH mutation status is not provided in this case and according to the current (2016) WHO classification of CNS tumors, this tumor would, therefore, be designated as a diffuse astrocytoma NOS.

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Case information

rID: 23788
Published: 8th Jul 2013
Last edited: 14th Aug 2019
Tag: tumour
Inclusion in quiz mode: Included

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