Diabetes insipidus as a main symptom of cancer

Hormonal disturbances are a possible complication of malignant disease not derived primarily from the endocrine cells. They may result from paraneoplastic hormonal activity of the tumor, such as frequently described Cushing’s syndrome in the course of ectopic secretion of adre-nocorticotropic hormone (ACTH), a syndrome of inappropriate secretion of antidiuretic hormone (SIADH) and malignancy related hypercalcemia. Endocrinopathy may also be due to the destruction of the organ of inter-nal secretion by the local invasion or distant tumor metastasis, such as secondary lesions in the hypothalamic-pituitary area. Thus, the clinical picture of malignancy sometimes may be dominated by the symptoms of hormonal deficiency. Diabetes insipidus (DI) is a rare complication of neoplastic disease, and its presence requires extended diagnostics. We present two case reports of patients with metastases to the pitu-itary gland (MP) without an incriminating history suggesting malignancy, where DI was only the tip of the iceberg called cancer. Careful clinica