Are biochemical markers of neuroendocrine tumors coreleased with insulin following local calcium stimulation in patients with insulinomas?

Objectives: The objective was to test whether chromogranin A (CgA), neuron-specific enolase (NSE), and pancreatic polypeptide (PP) are released from the pancreas during the selective arterial calcium stimulation and hepatic venous sampling test (ASVS) in patients with insulinomas.

Methods: We determined CgA, NSE, PP, insulin, C-peptide, and proinsulin in blood samples obtained during the ASVS test in 19 patients with insulinomas. Levels following calcium injection into the arteries supplying the tumor were compared with levels following calcium stimulation of arteries supplying healthy pancreatic tissue.

Effect of pituitary surgery in patients with acromegaly on adiponectin serum concentrations and alanine aminotransferase activity.

Background: Thiazolidinediones increase adiponectin concentrations, improve insulin sensitivity and fatty liver disease (reflected by decreased alanine aminotransferase [ALT] activity) in type 2 diabetes. This study was performed to test the effect of neurosurgery in acromegaly (sharing at baseline insulin resistance but not increased visceral fat with type 2 diabetes) on insulin sensitivity, adiponectin concentrations and ALT activity.

Methods: Sixteen patients with acromegaly undergoing pituitary surgery (and 16 patients with type 2 diabetes treated with pioglitazone) were included.

Assessment of hyperinsulinaemia at the termination of the prolonged fast.

Background: Traditional criteria to diagnose hyperinsulinaemic hypoglycaemia are based on insulin measurements by unspecific insulin assays. This study was performed to test whether these traditional criteria can be applied when insulin is measured by specific immunoassays.

Methods: 29 consecutive patients undergoing a prolonged fast were included; 11 patients with insulinoma and 18 healthy individuals.