Neuro Teaching Set

Focal tumor necrosis and rare pleomorphic nuclei. Rare mitotic figures are noted, with the Ki-67 <1%. EMA is positive.

The signs of anaplasia are very atypical neoplastic cells and focal high cell density. There are no substantial endothelial reaction or tumor necrosis evident.

The tumor is focally cellular, but mitotic figures are rare and Ki-67 is no greater than 1%. PCNA is equivocal due to technical factors.

The sarcomatous areas stain strongly with CD-34 and variably with vimentin and Masson's trichrome stain. CD-31 and reticulin do not significantly mark sarcomatous areas.

The tumor is an infiltrating malignant glioma that is highly anaplastic. It has a high mitotic rate and extensive necrosis.

This glioma has unusual features and is difficult to classify and grade histologically. It has sheets and nests of infiltrating cells that are not well differentiated.