Department of Pathology,
University of Oklahoma Health Sciences Center
Answer: B (Central neurocytoma)
Level of difficulty: 3
- Pathology of the case: This is an interesting
cytologic preparation. The nuclei are hyperchromatic and lack pleomorphism. In
fact, they look monotonous. The long cytoplasmic processes that are seen in
glial neoplasm are also here (Panel
features are suggestive of a glial neoplasm. The interesting point is that the
cells seems to arrange in a rosette with an imaginary center. When this
features is considered with the clinical features (35 year-old patient with an
exophytic, ventricular mass) are highly suggestive of a central neurocytoma.
The major differential diagnosis is ependymoma and, less likely, other glial
tumors such as low-grade astrocytomas and oligodendrogliomas. In reality, it
is quite difficult or impossible to distinguish neurocytoma from other low
grade neoplasms on squash preparations [Click
here to see a cyotologic preparation of an oligodendroglioma].
The histologic sections of this tumor is shown in low-magnification (Panel
Neurocytomas often occur as monotonous tumor with clear cytoplasm. They may
have islands of neuropils (Þ)
in Panel B. It is very likely that the cytologic photo being shown corresponds
to these neuropil islands. In contrast to oligodendrogliomas, neurocytomas are
strongly positive for synaptophysin and other neuroendocrine markers.
here to see another case of neurocytoma]
meningiomas may arise in the tela choroidea or in the stroma of the choroid
plexus with a distinct preference to the left ventricle as an exophytic mass.
The cytologic features, however, is not typical for a meningioma. Nuclei of
meningiomas are usually more open, round to oval, and often contain inclusion.
Tumor cells arranged in whorls are also commonly seen in meningiomas.
- Subependymoma giant cell astrocytoma:
They are characterized by large, bizarre looking giant cells which are
totally lacking here. However, they typically occur as intraventricular
exophytic tumors in patients with