[A rare case of hypoglycemia in an elderly patient with type 2 diabetes mellitus: malignant metastasizing insulinoma].

The incidence of insulinoma, an insulin-producing tumour arising from pancreatic beta-cells and responsible for the development of fasting hypoglycemia, in the general population is 1-4 per 1,000,000 yearly, mostly at the age of 25-55 yr. Malignization of this neoplasm occurs in 10-15% of the cases. One third of the tumours produce metastases.