Hypercortisolaemia due to ectopic adrenocorticotropic hormone secretion by a nasal paraganglioma: a case report and review of the literature

BACKGROUND: Adrenocorticotropic hormone-producing extraadrenal paragangliomas are extremely rare. We present a case of severe hypercortisolemia due to ectopic adrenocorticotropic hormone secretion by a nasal paraganglioma. CASE PRESENTATION: A 70-year-old Caucasian woman was emergently admitted to our department with supraventricular tachycardia, oedema of face and extremities and hypertensive crisis. Initial laboratory evaluation revealed severe hypokalemia and hyperglycemia without ketoacidosis, although no diabetes mellitus was previously known. Computed tomography revealed a large tumor obliterating the left paranasal sinus and a left-sided adrenal mass. After cardiovascular stabilisation, a thorough hormonal assessment was performed revealing marked adrenocorticotropic hormone-dependent hypercortisolism. Due to the presence of a cardiac pacemaker magnetic resonance imaging of the hypophysis was not possible. [(68)Ga-DOTA]-TATE-Positron-Emission-Tomography was performed, showing somatostatin-receptor expression of the paranasal lesion but not of the adrenal lesion or the hypophysis. The paranasal tumor was resected and found to be an adrenocorticotropic hormone-producing paraganglioma of low-proliferative rate. Postoperatively the patient became normokaliaemic, normoglycemic and normotensive without further need for medication. Genetic testing showed no mutation of the succinatdehydrogenase subunit B- and D genes, thus excluding hereditary paragangliosis. CONCLUSION: Detection of the adrenocorticotropic hormone source in Cushing’s syndrome can prove extremely challenging, especially when commonly used imaging modalities are unavailable or inconclusive. The present case was further complicated by the simultaneous detection of two tumorous lesions of initially unclear biochemical behaviour. In such cases, novel diagnostic tools - such as somatostatin-receptor imaging - can prove useful in localising hormonally active neuroendocrine tissue. The clinical aspects of the case are discussed and relevant literature is reviewed.