Cushing's syndrome due to ectopic adrenocorticotropic hormone production by a non-metastatic gastrinoma after long-term conservative treatment of Zollinger-Ellison syndrome

This report concerns a case of a Cushing's syndrome 10 years after first diagnosis of a Zollinger-Ellison syndrome within the same patient. In a 69-year-old female patient symptoms of hypergastrinaemia have been successfully treated with a proton pump inhibitor. Cushing's syndrome was the result of ectopic adrenocorticotropic hormone production by a large cystic gastrin-producing tumour of the pancreatic tail. After resection by subtotal pancreatectomy serum adrenocorticotropic hormone, cortisol, gastrin levels and secretin infusion test returned to normal. In contrast to all other previously published cases of ectopic adrenocorticotropic hormone syndrome associated with Zollinger-Ellison syndrome, this tumour had not metastasized into the liver and did not show local invasive growth.