Pilocytic astrocytoma of the neurohypophysis

Pilocytic astrocytoma of the neurohypophysis are rare and represent a pilocytic astrocytoma involving, or perhaps arising from, the infundibulum of the pituitary gland.

Terminology

The most important issue when trying to come to grips with this topic is to recognize is that these tumors are not thought to be the same as pituicytoma or for that matter granular cell tumors of the pituitary region, both of which are separate and distinct entities under the current (2016) WHO classification of CNS tumors . This is crucial, as some older reports use the term synonymously with pituicytoma, thus confusing the literature even further .

Other case reports have suggested that although these tumors are pilocytic astrocytomas they are nonetheless distinct lesions . It is probably, however, safer to consider them as a part of optic pathway gliomas (sometimes also referred to by the more accurate but cumbersome term hypothalamic-optochiasmatic gliomas).

This seems to be the stance of the WHO classification of CNS tumor which does not explicitly recognize pilocytic astrocytoma of the neurohypophysis as a distinct entity .