Glucagonoma is a rare, functioning type of pancreatic neuroendocrine tumor (PNET; see this term) that hypersecretes glucagon, leading to a syndrome comprised of necrolytic migratory erythema, diabetes mellitus, anemia, weight loss, mucosal abnormalities, thromboembolism, gastrointestinal and neuropsychiatric symptoms.

Cerebellar ataxia refers to ataxia due to dysfunction of the cerebellum. This causes a variety of elementary neurological deficits including asynergy (lack of coordination between muscles, limbs and joints), dysmetria (lack of ability to judge distances that can lead to under- oder overshoot in grasping movements), and dysdiadochokinesia (inability to perform rapid movements requiring antagonizing muscle groups to be switched on and off repeatedly).