Two cases of multiple hormone‐producing small cell carcinoma of the lung. Coexistence of tumor ADH, ACTH, and β‐MSH

Two cases of small cell carcinoma of the lung associated with the ectopic production of multiple hormones are reported. Both tumors were shown to contain significant amounts of ADH, ACTH, and β‐MSH. Biologic, immunologic, and gel chromatographic properties of these ectopic hormones were found to be very similar to those of pituitary origin. The effect of excessive secretion of antidiuretic hormone (ADH) dominated the clinical manifestations in both cases, i.e., syndrome of inappropriate secretion of ADH (SIADH). The clinical manifestations of the ectopic ACTH‐MSH syndrome were minimal. These data suggest that multiple hormone production without clinically overt sequelae of excess hormone is not uncommon in small cell (oat cell) carcinoma of the lung.