2007 Volume 47 Issue 2 Pages 125-130
Background. Brain metastasis is often seen in patients with lung cancer; however, the reported incidence of pituitary metastasis is rare. We present a case with central hypopituitarism secondary to pituitary metastasis from lung cancer. Case. A 78-year-old woman had been receiving treatment on an outpatient basis at a local hospital for the control of diabetes mellitus since 1998. A chest roentgenogram revealed a huge mass in the middle lung field of the left lung in February, 2006 and she was referred to us. A bronchoscopic biopsy in March revealed adenocarcinoma. Systemic examinations showed multiple lung metastases and bone metastases, and brain MRI also showed focal metastasis to the right occipital lobe, thus indicating a clinical stage of T4N3M1 (stage IV). She was admitted to our department due to severe appetite loss for 1 week. She complained of polyuria, thirst, and polydipsia. We performed a hematological examination including basal endocrinological conditions, a high concentration saline loading test, the response to desmopressin administration, and the findings of brain MRI, which led to a diagnosis of metastasis of lung cancer to the pituitary gland with central diabetes insipidus. Although chemotherapy did not improve the symptoms of diabetes insipidus, the intranasal administration of desmopressin improved them. Her appetite loss promptly improved after the administration of desmopressin. Conclusion. We should suspect the possibility of a metastatic pituitary tumor in a patient has diabetes insipidus. If such tumors can be accurately identified, appropriate treatment can result in an improvement in the quality of life for patients with advanced lung cancer.
