Sections show a densely cellular lesion with numerous astrocytes, mitoses, and endothelial proliferation. The initial impression was that of an astrocytic neoplasm, probably an anaplastic astrocytoma, however, the attending pathologist also noted some other features (example 1 and example 2) which led him to send these slides to us for consultation. After examining the slides, we requested the paraffin blocks and performed some special stains to confirm our diagnosis.
What other diagnoses were considered in this case?
What special stains helped to confirm this?