Elevated plasma and tissue concentrations of beta-endorphin and beta-lipotropin associated with an ectopic ACTH-producing lung tumor

beta-Endorphin- and ACTH-like immunoreactive peptides were measured in plasma and certain tissues of a patient suffering from an oat-cell-carcinoma of the lungs and Cushing's syndrome. Using sensitive radioimmunoassays in combination with gel-filtration, highly elevated levels of beta-endorphin, beta-lipotropin (beta-LPH), alpha-melanotropin (alpha-MSH) and ACTH were found.