Approach to a patient with MEN1 syndrome.

MEN1 (multiple endocrine neoplasia type 1) is an uncommon, autosomal dominant inherited endocrine tumour predisposition syndrome. The most common manifestations of MEN1 are primary hyperparathyroidism, pancreatic neuroendocrine tumours and pituitary adenomas. Individuals with MEN1 benefit from lifelong surveillance, with the aim of detecting MEN1 manifestations early. The ideal timepoint for interventions needs to be carefully selected in the context of the syndrome. Published guidelines help clinicians to navigate the management and follow up of individuals with MEN1. This article aims to explore some of the nuance in the investigation and management of this often complex condition from an endocrinologist's point of view, through exploration of 4 clinical case vignettes.