Familial Isolated Pituitary Adenomas

Over the last century several families have been described with familial isolated pituitary adenomas (FIPAs). Most commonly, family members have acromegaly or prolactinoma, but other types of pituitary adenomas can also occur. Recently, mutations in the AIP (aryl hydrocarbon receptor interacting protein) gene have been found to occur in 30–50% of FIPA patients, while for the rest of the patients the gene causing the disease is currently unknown and is a topic of intense research. Tumours in patients with AIP mutations are diagnosed at significantly younger ages and tend to be larger. Often the response to medical therapy in these patients is poor. This article discusses the clinical and genetic characteristics of this relatively recently recognised disease.