One hundred years after the discovery of insulin and glucagon: the history of tumors and hyperplasias that hypersecrete these hormones.

One century ago, in 1922, Frederick G Banting, Charles H Best, James B Collip and John J R Macleod first published their experiments resulting in the isolation of a hypoglycemic factor, named insulin, from a solution extract from a dog's pancreas. One year later, in 1923, a hyperglycemic factor named glucagon was isolated by Charles P Kimball and John R Murlin. In the following years, it could be demonstrated that pancreatic islet alpha- and beta-cell neoplasms and hyperplasias could inappropriately secrete excessive amounts of these two hormones. This review is a sequel to the discovery of insulin and glucagon and introduces the history of this fascinating group of neuroendocrine neoplasms and hyperplasias of the pancreas.