Granular cell tumor of the neurohypophysis: case report and review of the literature.

A 54-year-old woman presented with a stalk mass that was discovered incidentally with mild visual fields defect. The mass was operated surgically by the fronto-temporal approach, and histology met the diagnosis of neurohypophesial granular cell tumor (GCT). After surgery, the patient suffered from an irreversible severe bi-temporal visual deficit and an irreversible hypopituitarism. We review the literature and discuss the clinical nature of GCTs, treatment options and outcome. In an effort to avoid the severe complications that may result from surgical removal of neurohypophesial GCT, we discuss also the possibility of choosing the conservative approach with close follow-up. The tumor's firm consistency, tendency to hemorrhage, involving the pituitary stalk and lack of dissection plane from basal brain structure render surgery difficult, and maximal resection often requires sacrificing the stalk. Moreover, small asymptomatic neurohypophysial GCTs are common findings, most probably benign tumors with slow growing nature. Hence, for a neurohypophesial tumor which is suspected to be a GCT, we offer to consider the alternative approach, with close clinical, visual field and radiological study follow up.