Question

A 36-year-old woman comes to the clinic complaining of a tonic-clonic seizure. CT of the brain reveals an intracranial mass. Biopsy is positive for synaptophysin and negative for glial fibrillary acidic protein. Which of the following cells is likely the origin of this tumor?

A) Astrocytes
B) Ependymal
C) Oligodendrocytes
D) Meningioepithelial cells
E) Neurons

Answer 1

The intracranial tumor is positive for synaptophysin, indicative of neuronal origin, and negative for GFAP, ruling out an astrocytic origin, thus the tumor likely originates from neurons.

Step-by-step explanation:

The biopsy findings from the 36-year-old woman with a tonic-clonic seizure indicate the presence of a brain tumor. The tumor is positive for synaptophysin, which is a marker for neuronal and neuroendocrine cells, and negative for glial fibrillary acidic protein (GFAP), which is a marker for astrocytes. Therefore, the cells likely at the origin of this tumor are neurons (E), not the other types of glial cells such as astrocytes (A), ependymal cells (B), oligodendrocytes (C), or meningioepithelial cells (D).