Unusual Presentation of Case of a Lung Carcinoid Tumor With Ectopic Adrenocorticotropic Secretion (EAS) Associated With Acute Weight Gain and Peripheral Edema

Ectopic adrenocorticotropic secretion (EAS) is classically related to small-cell lung cancer but is caused by a wide variety of tumors. In approximately one-fifth of cases, the cause remains unidentified. Excess adrenocorticotropic hormone (ACTH) leads to Cushing's syndrome, and the presentation can be due to biochemical derangements such as hypokalemia and hyperglycemia. Alternatively, it may manifest with secondary symptoms such as weight gain, hypertension, skin thinning, abdominal striae, and/or psychotic manifestations. The diagnosis is established through dynamic testing after confirming excess cortisol and ACTH levels. Imaging is then used to identify the hormonally active lesion. Controlling hypercortisolism with steroidogenesis inhibitors is the initial step before proceeding to definitive treatment. Ideally, tumor resection, if possible, but bilateral adrenalectomies are considered in cases not amenable to curative surgery.