Presentation
Headaches and first seizure.
Patient Data
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.
Histology
MICROSCOPIC FINDINGS
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.
Discussion
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.