Metastatic Pituitary Tumor presenting as Bitemporal Visual Field Defects

Abstract

Autopsies fairly often reveal metastatic malignant tumors in the pituitary gland, but most were asymptomatic when the patients were alive. The literature contains only 11 reports of cases in which such tumors manifested as bitemporal visual field defects. The authors present the case of a 57-yearold male with bitemporal visual field defects due to pituitary metastasis from a pulmonary small cell carcinoma. Diabetes insipidus was the most remarkable finding in this patient, but anterior lobe involvement was also documented. Skull X-rays showed only minimal abnormality of the sella, but computed tomography revealed a high-density suprasellar mass 1.5 cm in diameter. The tumor was isointense on T2-weighted magnetic resonance imaging. The tumor was partially removed through a frontal craniotomy and postoperative irradiation was administered. The tumor was markedly reduced in size and the visual field defects abated.