[A case of non-functional pituitary adenoma associated with Rathke's cleft cyst].

A very rare case of non-functional pituitary adenoma associated with Rathke's cleft cyst is reported. A 42-year-old male suffering from visual disturbance and headache was admitted. Visual acuity was 1.2 on the right and 0.5 on the left, and visual field examination showed bitemporal hemianopsia. Endocrinological study disclosed that the basal serum level of prolactin was elevated slightly to 52.6 ng/ml, whereas those of other hormones were within normal limits. MRI showed a dumbbell-shaped cystic sellar mass extending to the suprasellar region beyond the diaphragm sellae, which consisted of two isolated components around the sellar turcica. At the middle of May, the tumor was partially removed by bifrontal craniotomy. The suprasellar tumor tightly adhered to the frontal lobe and the optic nerve, the tumor was grayish cyst and cyst fluid from the suprasellar mass had the appearance of motor oil and the intrasellar tumor contained old hematoma. Histological findings revealed that the suprasellar mass was Rathke's cleft cyst and the intrasellar mass was diagnosed as pituitary adenoma (non-functional). Visual acuity was improved following surgical operation. So far twenty-three cases of pituitary adenoma associated with Rathke's cleft cysts have been reported in the literature, but there was only one case reported of a non-functional pituitary adenoma associated with a Rathke's cleft cyst. Etiology and pathogenesis of the coexistence of non-functional pituitary adenoma and Rathke's cleft cyst in the present case were not elucidated.