Answer and Discussion of Quiz Set: N-017

3.    Which of the following locations are most common for pilocytic astrocytoma?

A.  Frontal and parietal lobe of the cerebral hemispheres

B.  Cerebellum

C.  Brainstem (midbrain, pons, medulla)

D.  Spinal cord

E.  Optic nerve

Answer and Discussion: The answer is (B). Although the incidence of astrocytic tumors and oligodendrogliomas are proportional to the amount of white matter, pilocytic astrocytoma is a violator. Most of them occur in the cerebellum. In patients with neurofibromatosis 1 (NF1) has a much higher frequency of pilocytic astrocytomas arising in the optic nerve-hypothalamus axis and these tumor are seen in children.