Pituitary metastases are rare, and metastatic pituitary lesions originating from endometrial adenocarcinoma are extremely rare. These lesions can be mistaken for pituitary adenomas and their diagnosis can be very difficult. Pituitary metastases mostly affect the posterior lobe and patients may develop diabetes insipidus. Patients with endometrial cancer complicated with diabetes, including poor glycemic control, may also suffer from thirst, making it more difficult to diagnose diabetes insipidus. A 68-year-old woman who was being followed-up for primary endometrial adenocarcinoma was admitted for gradually worsened polyuria and polydipsia. Her laboratory findings were compatible with diabetes insipidus. Magnetic resonance imaging revealed thickening of the pituitary stalk, involvement of the superior pituitary gland, and disappearance of hyperintensity in the posterior lobe, indicating pituitary metastasis. Increased urine output and oral fluid intake in a patient with a diagnosis of carcinoma may indicate possible pituitary metastasis, and the hormonal insufficiency should be corrected to improve the patient's quality of life.
Keywords: Diabetes insipidus; endometrial adenocarcinoma; metastasis; pituitary; thirst; urine output.