Impaired glucose tolerance in patients with pancreatic cancer

Pancreatic cancer is the fifth leading cause of cancer death in western countries. It is almost uniformly fatal with dismal 6-month survival from diagnosis. Diabetes or impaired glucose tolerance occurs in up to 60-81% of patients with pancreatic adenocarcinoma. The reason for the frequency with which diabetes is associated with pancreatic cancer is controversial. Diabetes was previously thought to be a predisposing factor for the disease. Recent investigations indicate that diabetes or impaired glucose tolerance is a consequence of pancreatic cancer rather than a predisposing factor for its development. The diabetic state in patients with pancreatic cancer is characterized by high plasma levels of insulin and by reduced body insulin sensitivity. In addition, plasma concentrations of several other pancreatic peptides, such as islet amyloid polypeptide, glucagon and somatostatin, are increased. The decrease in the glucose metabolic rate in patients with pancreatic cancer demonstrated a state of peripheral insulin resistance, which was more severe in diabetic patients than in nondiabetic patients. Some authors have suggested that pancreatic cancer may produce a specific factor that is important in the development of diabetes. A possibility for decreasing mortality from pancreatic cancer is the application of screening and treatment for early pancreatic cancers in patients with new-onset diabetes with invasive and non-invasive imaging tests.