[Diabetes insipidus revealing pituitary metastasis of bronchial carcinoma]

Pituitary metastasis are rare but represent an important differential diagnosis of intrasellar tumorous syndromes. We report one case of intrasellar metastasis of a bronchial adenocarcinoma in a 50 year old woman. Clinical syndrome associated a tumorous syndrome (cephalalgia, bitemporal hemianopsia) and an anterior and posterior hypopituitarism biologically proven. A large intra and suprasellar mass which compressed the optic chiasma and highly enhanced after gadolinium injection was found by nuclear magnetic resonance imaging. The surgical biopsy displayed a pituitary metastasis of a right inferior lobar bronchial adenocarcinoma with bone secondary localizations. Cerebral radiotherapy and corticotherapy allowed recovery of visual loss but did not prevent rapid death. The clinical and radiological features which may evoke an intrasellar metastasis were: the tumorous syndrome associated with or revealed by diabetes insipidus, loss of spontaneous hypersignal of the neurohypophysis in nuclear magnetic resonance imaging, bulking pituitary stalk, bilobar character of the mass which is in favour of rapid cell proliferation, postero-superior extension, lowering of the V3 floor and very strong and homogeneous signal after gadolinium injection.