Endocrine Abstracts

Introduction: Ectopic ACTH syndrome (EAS) is a rare cause of ACTH-dependent endogenous hypercortisolism.

Objective: The objective of this study was to analyse the clinical, biochemical, and radiological features, management, and treatment outcome of patients with EAS.

Design: It was a retrospective case-record study of 52 patients with EAS.

Materials and methods: Clinical, biochemical, and radiological features and response to therapy and survival were measured.

Results: The median follow-up was 7 years (range, 1–13 years). None of the dynamic tests achieved 100% accuracy. Imaging correctly identified the lesion at first investigation in 83% of cases. Bronchial carcinoid tumors were the most common cause of EAS (n=34; 65.4%), followed by other neuroendocrine tumors (n=13, 25%). In 9.6% (5) of patients, the source of EAS was never found. Octreotide scintigraphy and whole-body venous sampling were of limited value. Surgical attempt at curative resection was successful in 83% (43 of 52) of all patients; 9 (19.1%) responded generally well to bilateral adrenalectomy by vital necessity. Tumour histology and the presence of distant metastases were the main predictors of overall survival (P<0.05).

Conclusions: No single test provides to find the source of EAS correctly. Despite a variety of tests and imaging studies for the correct diagnosis of the EAS, up to 10% of cases present an occult EAS. These cases require a prolonged follow-up, review, and repetition of diagnostic tests and scans, but, if it is necessary, do bilateral adrenalectomy.