Endocrine Abstracts

Te paraneoplastic Cushing’s syndrome represents 9 to 18% of ACTH-dependent endogenous hypercorticisms; which poses, in clinical practice, two types of problems:

– on the one hand, the differential diagnosis with Cushing’s disease, when well differentiated and morphologically undetectable endocrine tumors are involved.

– on the other hand, the control of hypercortism, most often major in metastatic neuroendocrine tumors, which can in itself compromise the vital prognosis.

This is the case of our young patient, aged 26 years, who presents a Cushing’s syndrome of rapid onset (after 4 months), marked by the intensity of the signs of hyperandrogenism with a severe hypokalemia of the order of 1.8 mEq/l, complicated by diabetes mellitus, hypertension and psychosis. Basal endocrine (ACTH: 905 pg/l, plasma cortisol: 2589 nmol/l) and pharmacodynamic (non-blocking with Dexamethasone) exploration, as well as non-visualization of a pituitary adenoma on hypothalamic-pituitary MRI, led us to favorize the diagnostic of hypercorticism by ectopic tumor secretion of ACTH. Thoracic CT scan found a right middle lobar lung tumor; an anapathological study of the bronchial biopsy, performed under bronchoscopy, revealed an atypical carcinoid tumor of the lung with mediastinal lymph node invasion. During the etiological investigation, and in view of the significant hypercorticism, anti-cortisol therapy was instituted, namely: LYSODREN* 2 gr/day per os, FLUCONAZOLE* 600 mg/day in IV, SANDOSTATINE* 400 mg/day subcutaneously, with weekly control of the renal, hepatic and lipid balance sheet. This therapy allowed a reduction of cortisol to more than 40% (1524 nmol/l) at D15 of treatment, allowing a normalization of hypokalemia resulting clinically in an attenuation of the signs of hyper androgenism and psychosis. The study of this case illustrates the characteristics of a paraneoplastic Cushing’s syndrome indicative of a carcinoid lung tumor, and the usefulness of anti-cortisol therapy in the control of hypercorticism pending etiologic treatment.