Small cell lung carcinoma with ectopic adrenocorticotropic hormone and antidiuretic hormone syndromes: a case report

This report describes a 63-yr-old man with lung cancer accompanying hypertension, hyperpigmentation, muscle weakness, psychosis, hypokalemia, hyperglycemia, hyponatremia, massive natriuresis and lower serum osmolality than urine osmolality. Elevated levels of plasma and urine corticosteroids and of plasma immunoreactive adrenocorticotropic hormone (ACTH) were not altered by the administration of large amounts of dexamethasone. Elevated plasma antidiuretic hormone (ADH) values were also demonstrated. Postmortem examinations revealed small cell lung carcinoma with extensive metastasis, bilateral adrenocortical hyperplasia and Crooke's degeneration of the pituitary gland. Immunoradiological and immunohistochemical studies demonstrated the presence of immunoreactive ACTH, ADH and gastrin-releasing peptide in the tumor tissue. Beta-melanocyte-stimulating hormone, calcitonin and carcinoembryonic antigen were also detected by one of the methods. Hence, this is a rare case of lung cancer with multiple hormone production and clinical and laboratory evidence of both the ectopic ACTH and ADH syndromes.