Abstract. Glucagonoma is a rare neuroendocrine tumor with pancreatic alpha cell differen­tiation. This tumor is characterized by hypersecretion of a peptide hormone glucagon, which can be detected in this type of neoplasia. The majority of tumors are malignant and most patients already have a metastasis. The average patient age at the time of tumor discovery is 52.5 years. A characteristic, although not a pathognomonic sign of the tumor is a skin rash in the form of necrolytic migratory erythema. Along with diabetes or glucose intolerance, weight loss or cahexia, thromboembolic problems, anemia and diarrhea are the main signs of glucagonoma syndrome.