Abstract
Introduction. - Paraneoplastic Cushing's syndrome is a rare cause of endogenous hypercorticism. It is caused by ectopic secretion of ACTH by a non-pituitary endocrine tumor. The aetiological biological and radiological data are often inconclusive, which creates a problem of differential diagnosis with Cushing's disease. In addition, these tumors are often small and their location is extremely variable. As a result, the difficulties of localization require the use of specific imaging techniques.Observation. - We report the observation of a 44-year-old man suffering from diabetes and high blood pressure, presenting a severe and rapidly progressive Cushing syndrome, in connection with a hypercorticism caused by an ectopic ACTH secretion. The thoracic computed tomography performed within the framework of a search for a neoplastic origin objectified a 15 mm nodule isolated at the level of the middle lobe, the scintigraphy with octreotide marked with indium-111 found a significant fixation at the level of the lung nodule. The patient had a middle lobe lobectomy. The outcome was favorable with regression of Cushing's syndrome. Pathological examination was in favor of a typical carcinoid tumor, and the immunohistochemical complement showed tumor cell positivity for ACTH, CD56, chromogranin, and synaptophysin.Conclusion. - This observation illustrates the dilemma between the need to locate an ectopic ACTH secretion and the control of aggressive and threatening Cushing's syndrome. Early use of the octreotide scintigraphy should be considered if a topographic diagnosis of the causative tumor cannot be done through conventional imaging techniques.
Highlights
Paraneoplastic Cushing’s syndrome represents 10 to 17% of adenocorticotropin (ACTH) dependent Cushing syndrome cases
In Cushing's disease, the pituitary adenoma is sensitive to the high-dose dexamethasone suppression test, and to corticotropin-releasing hormone (CRH) stimulation test
Ectopic ACTH secretions are a rare cause of Cushing's syndrome
Summary
Paraneoplastic Cushing’s syndrome represents 10 to 17% of adenocorticotropin (ACTH) dependent Cushing syndrome cases. It induces, in its classical form, a major and rapidly evolving hypercorticism [1,2]. In its classical form, a major and rapidly evolving hypercorticism [1,2] This ectopic secretion is secondary to neuroendocrine tumors with variable size and location, but the most frequent are lung carcinoid tumors [1]. Few studies reported cases of paraneoplastic Cushing’s syndrome, what motivated us to report the case of a patient presenting with a severe and rapidly progressive Cushing's syndrome caused by a typical lung carcinoid tumor. The course, one month after surgery with hormone replacement therapy, was marked by an important clinical improvement, a normalization of blood pressure and blood sugar levels, a collapsed 8-hour cortisol level and a normal serum potassium of 4.2 mmol / L
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
