Long-term outcome of Multiple Endocrine Neoplasia type 1 related manifestations : Results from the DutchMEN1 Study Group

Multiple Endocrine Neoplasia type 1 (MEN1) is a rare syndrome caused by mutations in the MEN1 gene on chromosome 11. It is characterized by the occurrence of primary hyperparathyroidism (pHPT), duodenopancreatic neuroendocrine tumours (NET), pituitary tumours, adrenal adenomas and NET of the stomach, bronchus and thymus. The research in this thesis focusses on the long-term outcome of MEN1 related manifestations. Since the discovery of the MEN1 gene in 1997, presymptomatic genetic testing became available. In the research described in chapter 3 we show that patients with a genetic diagnosis had less manifestations at the end of follow-up and no MEN1 related malignancy or death, compared to patients with a clinical MEN1 diagnosis. Primary hyperparathyroidism is the most prevalent MEN1 manifestation and responsible for most MEN1 related surgeries. The optimal surgical strategy for MEN1 related pHPT is under debate. In chapter 4 we present the results of 52 patients who underwent primary surgery for MEN1 related pHPT. Of the patients who underwent less than subtotal parathyroidectomy (