[Pituitary stalk metastasis from lung cancer, preceding diabetes insipidus--case report and clinical review of the literature].

A 59-year-old woman whose first clinical manifestations were polyuria and polydipsia was admitted to our hospital. Brain MRI showed multiple mass lesions and a thickened pituitary stalk. Chest CT showed hilar and mediastinal lymphadenopathy and a small nodule measuring about 1.5 cm in the apex of the right lung. Histopathological examination revealed adenocarcinoma of the lung, and primary lung cancer with diabetes insipidus secondary to pituitary stalk metastasis was diagnosed. She received systemic chemotherapy and whole-brain irradiation concurrent with intranasal desmopressin (DDAVP) treatment. Although the size of the tumor was reduced, her symptoms did not improve and the same dose of hormone replacement therapy was required. We present this rare case and review the twenty cases of metastatic pituitary lesions arising from lung cancer reported in the literature.