Stacpoole [5] reported that all of the following criteria should be satisfied to diagnose a glucagonoma: demonstration of a tumor mass by direct visualization or radiographic techniques; proof that the tumor shows a preponderance of glucagon-containing cells on appropriate staining and/or proof of increased tissue levels of immunoreactive glucagon; elevation of basal circulating immunoreactive glucagon; and at least one of the following coincidental findings; (a) skin rash, (b) glucose intolerance, or (c) hypoaminoacidemia. Here, GCG is linked to neoplasm.