The association of large pituitary mass, lack of clinical syndromes of pituitary hypersecretion, hypopituitarism and visual field defects suggests the diagnosis of nonfunctioning pituitary adenoma, but the same characteristics can be present in patients affected by other tumorous lesions, cysts, inflammatory processes or vascular disease. The management of these patients depends on a correct diagnosis. A 53-year-old woman was admitted for nausea, vomiting and severe hypotension. For three months she had complained of weakness, sleepness, skin-dryness and loss of weight. Imaging and endocrine evaluations revealed an intra and extrasellar mass causing hypopituitarism without diabetes insipidus. Histological examination of the tissue obtained at transsphenoidal surgery showed a Rathke's cleft cyst, surrounded by areas of noncaseous granulomatous tissue with scattered multinucleated giant cells of foreign body type, similar to a sarcoid lesion. Other systemic sarcoidosis localizations were absent. After two years of full well-being, the patient reported a sudden visual impairment, due to sarcoidosis involvment of the prechiasmatic tract of the optic nerve, that promptly improved with corticosteroid treatment. This report emphasizes the overlap of signs and symptoms between non functioning tumors and nontumoral masses of hypothalamic-pituitary region and underlines the fact that a correct diagnosis is feasible only on histopathological basis. Although, occasionally, the coexistence of Rathke'cyst with pituitary adenoma has been reported, to the best of our knowledge, this is the first report of the association between Rathke's cleft cyst and noncaseating granuloma tissue. Finally, the remission of neurolgical symptoms following corticosteroid therapy confirms this treatment as a valid medical approach and suggests its use in a short therapeutic trial when the diagnosis is doubtful. (C) 1997, Editrice Kurtis.