Neurosarcoidosis presenting as hypopituitarism and a cystic pituitary mass

We report a young woman with clinical hypopituitarism and systemic sarcoidosis involving the lung, gastrointestinal tract, and peripheral lymph nodes. Laboratory evaluation confirmed that cortisol, thyroid indices, insulin-like growth factor 1, follicle-stimulating hormone, luteinizing hormone, and estradiol levels were low, with a normal prolactin. Magnetic resonance imaging revealed a large cystic pituitary lesion compressing the optic chiasm and exhibiting rim but not hypothalamic enhancement. The differential diagnosis included cystic macroadenoma, Rathke's cleft cyst, craniopharyngioma, and simple cyst. A transsphenoidal procedure provided decompression and diagnosis: pathology was consistent with sarcoidosis. Postoperatively, the patient's neurosarcoid disease markedly worsened, requiring hypothalamic irradiation. To our knowledge, this is the first report of intracranial sarcoidosis presenting solely as a cystic pituitary mass. An awareness of this possibility is important to prevent inappropriate neurosurgical intervention and subsequent potential exacerbation of neurosarcoidosis.