What are the 2 most common types of neoplasms in the pineal region?
Germ cell tumours and pineal parenchymal tumours. Other neoplasms are primarily of glial orgin or arise outside the pineal gland (e.g. meningioma).
What is the most useful lab test to determine whether a lesion is a malignant germinoma?
ß-HCG (serum or csf).
MRI shows a hypervascular, invasive lesion with perifocal oedema and infiltration of the thalamus and superior tectal plate.