Ganglioglioma arising from olfactory sheath: A rare site of an uncommon tumor.

Gangliogliomas are rare slow growing tumors with a mixed population of dysplastic ganglion cells and glial components, reported at variable sites within the central nervous system, including the frontal, parietal and occipital lobes, the striatum, cerebellum, pituitary and pineal glands as well as the spinal cord. Rarely gangliogliomas have been reported arising within the cranial nerves, including the optic and trigeminal nerve. We present the first patient, to our knowledge, where such a tumor originated from the olfactory sheath. Migration defects leading to entrapment of sensory neurons during development is believed to be responsible for the pathogenesis of these lesions. The extent of surgical extirpation and histopathological anaplasia are important prognosticators. While gangliogliomas are rare tumors, it is crucial to consider them in the differential diagnosis of non-enhancing, poorly localized lesions along the cranial nerves.