Diabetes insipidus as the first symptom caused by lung cancer metastasis to the pituitary glands: Clinical presentations, diagnosis, and management

Background : Central diabetes insipidus (CDI), secondary to pituitary metastatic lesions, is uncommon; however, lung and breast cancer are the commonest malignancies to have metastases to the pituitary. Early management of systemic chemotherapy and pituitary irradiation might improve the prognosis of patients.
Aims : To investigate the clinical features, diagnosis, and management of CDI caused by lung cancer metastasis to the pituitary glands.
Materials and Methods : We retrospectively reviewed 10 patients who had CDI as their first symptom before their lung cancers were diagnosed. Their clinical presentations, anterior pituitary gland function, sellar magnetic resonance imaging (MRI), management, and prognosis were described.
Settings and Design : This retrospective cross-sectional clinical study was conducted in a medical college hospital.
Results : The patient′s mean age was 58.6±7.8 years. Diabetes insipidus was the main complaint when they were referred to our hospital. MRI revealed specific dumbbell-shaped masses in the sella turcica in five patients. In seven patients whose hormones were measured, the levels of hormones from adenohypophysis were abnormally low in six patients. The main treatments included surgery, systemic chemotherapy, and sellar irradiation. Although nine patients had poor prognoses, one patient has survived for more than 3 years, suggesting benefit from early diagnosis and treatment.
Conclusions : New-onset CDI might be the only symptom presented by the patients with pituitary metastasis (PM) from lung cancer. Dumbbell-shaped sellar masses in MRI are prone to the diagnosis of PM. A thorough examination for primary cancer should be carried out in these aged and elderly patients.