Islet cell tumors of the pancreas: clinico-biochemical correlations.

Islet cell tumors produce a spectrum of syndromes. Intensive investigations of these tumors have enhanced our understanding of cellular origin, physiology and biochemistry of the islet hormones. Biochemical studies on the hormones are helpful in the diagnosis and treatment planning of the islet tumors. For example, insulinoma and glucagonoma can be diagnosed more readily by demonstration of proinsulin and proglucagon-like components, respectively, in the blood. Similarly, measurement of vasoactive intestinal polypeptide is not only useful in the diagnosis, but also in the follow-up of patients with pancreatic cholera syndrome. This mini-review examines these and other clinico-biochemical correlates seen in islet tumors.