ACTH ‐secreting pancreatic neuroendocrine neoplasms: A case‐series

Ectopic Cushing's syndrome (CS) occurs rarely in patients with pancreatic neuroendocrine neoplasms. Early recognition of symptoms is critical given the high morbidity and mortality associated with CS. A database of pancreatic neuroendocrine neoplasms (NENs) seen at the Moffitt Cancer Center between 1/2008 and 4/2022 was reviewed and cases of ectopic CS were identified. Information was extracted on tumor characteristics, clinical signs and symptoms, therapies, and outcomes. Thirteen cases were identified, ranging in age from 16 to 65 years at the initial time of diagnosis (median 42). Twelve of 13 patients had metastatic tumors at presentation. All were well‐differentiated at diagnosis although two were described as transformed to poorly differentiated on rebiopsy. A total of 4 patients also experienced Zollinger‐Ellison syndrome. Three patients underwent bilateral adrenalectomy to manage uncontrolled CS. Median overall survival of was 56 months from the time of initial cancer diagnosis but only 18 months from diagnosis of CS. Our study showed that ectopic CS is a highly morbid condition when occurring in pancreatic NENs and is associated with aggressive disease. Bilateral adrenalectomy can be considered for syndrome control. To our knowledge, this is the largest institutional case‐series of ACTH‐secreting metastatic pancreatic NEN.