Aim: To study the prevalence of germline AIP mutations in a large cohort of patients seen in the Oxford Centre for Diabetes Endocrinology and Metabolism (OCDEM), United Kingdom, (UK), with sporadic pituitary adenomas diagnosed or with symptoms and a clinical history by the age of 40 years old.
Patients: A total of 130 patients with pituitary adenomas of all histotypes, who had no family history of pituitary adenomas and who were examined at Oxford University Hospital, OCDEM, a tertiary referral centre, between 2011-2013 were enrolled in this prospective study.
Methods:
Leukocyte-origin genomic DNA underwent sequence analysis of exons 1-6 and the flanking intronic regions of the AIP gene (NM_003977.2). Dosage analysis was by Multiplex Ligation-dependent Probe Amplification (MLPA), using MRC-Holland kit P244-B1.
Results:
AIP mutations were detected in 3 % of the 130 patients; comprising 4 of 51 patients with acromegaly (8 %), 0 of 43 patients with prolactinomas, 0 of the 20 patients with non-functioning adenomas, 0 of 15 patients with corticotrophic adenomas and 0 of 1 patient with thyrotrophic adenoma.
This is the first comprehensive report of AIP mutations sequenced in a large young sporadic pituitary adenoma cohort, in the UK. Published reports from European centres have much higher rates of near 12% in their cohorts. [1, 2]
Conclusion:
This prospective cohort study clarifies the prevalence of AIP gene mutations in young patients with sporadic pituitary adenomas in the UK population. Our cohort does not have nearly as frequent mutations as in the European cohort. We suggest focusing testing to GH secreting tumours. However, given the relative frequency of mutations, genetic testing is of importance as genetic counselling and screening of offspring is indicated.