Glucagonoma : Molecular Genetics
Molecular Genetics: Glucagonomas are a rare component of MEN type 1. About 13%-17% of glucagonomas occur in the setting of MEN type 1. However, very few MEN 1 patients develop glucagonoma. These case show mutations in FOXA2 gene which plays an important role in islet development. Sporadic glucagonomas may show biallelic inactivation of DAXX gene which (along with ATRX) regulates chromatin remodeling at the telomeric and pericentromeric regions. In glucagon cell hyperplasia and neoplasia, about 50% of cases show germline mutations in the GCGR gene on chromosome 17q25.3. The image shows a well-differentiated pancreatic neuroendocrine tumor with copious hyalinized stroma. The patient had full-blown glucagonoma syndrome.