Posterior pituitary astrocytoma: a rare tumor of the neurohypophysis: a case report.

Astrocytoma, or pituicytoma, of the posterior pituitary is a relatively rare entity consisting of poorly characterized glial tumor cells. We report two cases of posterior pituitary astrocytomas in middle-aged women presenting as focal lesions of the neurohypophysis. A review of the literature reveals only a few reports of this tumor, and there has been scanty discussion of the imaging findings of posterior pituitary astrocytomas compared with lesions of the anterior pituitary gland. This report reviews the clinical characteristics and imaging findings and discusses the differential diagnosis of these two cases.