Endocrine Abstracts

Introduction: The ectopic ACTH syndrome (EAS) is associated with a variety of malignancies, mostly of (neuro-)endocrine origin. Several series report on the relative contribution of EAS in the spectrum of Cushing’s syndrome. However, information on the incidence/prevalence of EAS in the setting of patients diagnosed with thoracic or gastroenteropancreatic (GEP) neuroendocrine tumours (NETs) is virtually absent.

Study design: In our tertiary academic referral centre for NET patients and also for patients with Cushing’s syndrome, a large consecutive series of thoracic NET and GEP NET patients was screened for the presence/occurrence of EAS.

Patients: Four hundred and ninety-one patients, diagnosed with thoracic or GEP NETs, referred between 1-1-2000 and 1-12-2009, were studied.

We differentiated between previous, synchronous and metachronous occurrence of EAS. Synchronous EAS was defined as occurring between 6 months before and 6 months after the date of first diagnosis of the thoracic or GEP NET.

Patients with MEN-1 were excluded. Small cell lung cancer was also excluded.

Results: This series comprised of 491 patients with thoracic and GEP NETs (258 males, 233 females; female to male ratio, 1.1:1; mean age, 58.1 years).

Ten patients (2.0%) had EAS (5 males, 7 females; mean age, 53.1 years). All patients had synchronous EAS. Five patients had a bronchial NET, three had a thymic NET and two had a pancreatic NET.

Conclusions: The incidence of EAS in patients with thoracic and GEP NETs is very low (2.0%).

In line with the literature thoracic NETs (thymis and bronchial carcinoids) were the most frequent cause of EAS. Pancreatic NETs are the most common GEP-NETs causing EAS.