An Endocrine Picture In Disguise: A Progressive Olfactory Neuroblastoma Complicated With Ectopic Cushing Syndrome

Abstract

ABSTRACT Objective: To describe a unique case of a 61-year-old patient presenting with ectopic Cushing syndrome as a paraneoplastic phenomenon due to adrenocorticotropic hormone (ACTH)-secreting bone metastasis of an olfactory neuroblastoma (ON). Methods: We report a detailed case, with clinical, biochemical, and imaging findings and compare it with existing literature. Results: A patient with an ON, with subsequent 10-year stable disease after initial craniofacial surgery, presented with paraparesis due to progressively metastasized ON disease located in the thoracic spine. During palliative chemotherapy, severe hypokalemia and muscle weakness developed, being part of paraneoplastic Cushing syndrome. Examination showed that metastatic bone lesions were mostly responsible for the ectopic secretion of ACTH, with just a few ACTH-secreting tumor cells located in the primary tumor. She was treated with a combination of ketoconazole and metyrapone that controlled cortisol levels. However, low potassium levels ...