Twenty-six patients with carcinoma of the lung and normal electrolytes were studied a t the University of Texas M. D. Anderson Hospital. The most significant findings were: elevated plasma ACTH, lack of diurnal rhythm, and failure of dexamethasone to suppress plasma A C T H in eight patients. T w o patients h a d oat cell carcinoma, three had squamous cell carcinoma a n d three had adenocarcinoma of the lung. ACTH-like material was found in the tumor tissue of one patient with squamous cell carcinoma. Plasma corticoids were elevated in 76% of the patients due to the effect of severe disease on the pituitary-adrenal axis a n d increased binding of plasma corticoids to plasma proteins. I t is suggested that increased productioii of estrogen from the adrenal cortex may play an important role i n the binding of cortisol to plasma protein. Plasma ACTH is the most reliable index i n diagnosing "nomendocrine" Cushing's syndrome; it is an effective indicator of response to treatment or in determining the emergence of functioning metastasis.
HERE IS EVIDENCE THAT CERTAIN MALIG-
T nant tumors of non-endocrine origin may he associated with clinical and biochemical alterations identical to those of classical Cushing's syndrome.4, lo, 11 This association was first described by Brown? in 1928. In some cases, the classical clinical features of Cushing's syndrome have been absent, but changes in body chemistry, including hypokaleinic alkalosis, hyperglycemia, glycosuria and increased corticoid excretion, are present. Many investigators have used the presence of hypokalemic alkalosis as a screening feature for From the