Context: Ectopic ACTH syndrome (EAS) in youngsters has seldom been reported and is poorly known.
Setting: We conducted a multicenter retrospective study involving 18 French tertiary hospitals. Cases of EAS presenting Cushing's syndrome before the age of 20 during the period from 1985 to 2008 were analyzed.
Patients: Ten patients aged 14 to 20 yr were identified and compared to 20 age-matched patients with Cushing's disease diagnosed during the same period.
Main outcome measures: Etiologies, clinical, biochemical and radiological features, prognosis, and treatment were described.
Results: Seven patients had well-differentiated neuroendocrine tumors (five bronchial carcinoids, one mediastinal lymph node, and one thymic), one had a poorly differentiated thymic carcinoma, one had a pleural Ewing's sarcoma, and one had a liver nested stromal epithelial tumor. At presentation, seven tumors were identified with computed tomography scanning and somatostatin receptor scintigraphy, and one with fluoro-18-L-dihydroxyphenylalanine positron emission tomography scan. Two carcinoids were occult and were identified during follow-up. Cushing's syndrome was more intense in EAS, but the clinical and biological spectrum overlapped with that of Cushing's disease. No dynamic test achieved 100% accuracy, whereas petrosal sinus sampling provided correct diagnosis in all patients tested. Medical treatment of hypercortisolism was successful in six of the eight patients with whom it was attempted, and bilateral adrenalectomy had to be performed in only two cases. Prognosis was good; nine patients with curative resection of the tumor were alive and cured (median follow-up, 6.5 yr), whereas one patient died.
Conclusions: EAS in youngsters displays many similarities to that described in adults. The diagnostic and therapeutic algorithms recommended in adults can be used in this population.