Sellar neuroblastoma mimicking a pituitary tumour: case report and review of the literature.

Neuroblastomas of the sellar region are exceedingly rare. Only 2 cases have previously been reported. Management of these tumours depends on the tumour's primary site, the patient's age and histopathological features. We are reporting the case of a 43-year-old woman who developed progressive bitemporal hemianopsia and visual loss, accompanied by amenorrhea and hyponatremia. Laboratory findings revealed a slightly elevated prolactin level. Cranial MR-imaging displayed an intrasellar and suprasellar lesion with a maximum diameter of 2.5 cm that was suspicious for a pituitary adenoma or tuberculum sellae meningioma. The tumour was approached via a pterional trepanation. Intraoperatively, the tumour was highly vascularized and adhesive to the optic chiasm, the floor of the third ventricle, the hypothalamus and the hypophyseal stalk. Postoperatively, vision improved and prolactin dropped to normal values, but hyponatremia persisted. Histopathological examination revealed a neuroblastoma with strong positivity for synaptophysin and chromogranin, MAP-2 protein and NeuN-antigen in the immunohistochemistry. No pituitary hormone receptors were expressed. The MIB-1 labelling index was positive in 5% of the cell nucleoli. In the further course, the patient underwent radiotherapy of the neuroaxis. A brief review of the literature is presented.