Acromegaly caused by ectopic growth hormone-releasing hormone (GHRH) secretion from a bronchial carcinoid tumour is very rare, accounting for fewer than 1% of cases of the disease. This case study highlights how difficult it can be to make the diagnosis.

Kyriakakis and colleagues clearly describe the biochemical, radiological and histopathological features. They emphasise that pituitary hyperplasia can be difficult to differentiate from an adenoma. This demonstrates the importance of reviewing the histology in a pituitary multidisciplinary team and of access to an experienced pituitary histopathologist. This case also shows the benefit of reviewing complex cases years after diagnosis, when new techniques are available.

Here, GHRH staining confirmed the diagnosis of ectopic GHRH secretion from the bronchial carcinoid tumour. A complete diagnosis could have implications for follow up and disease surveillance. A negative MEN1 gene test is particularly noteworthy, as this would have implications for follow up and further testing of family members.

Read the full article in Endocrinology, Diabetes & Metabolism Case Reports EDM-16-0104