Table 4. Diagnostic tests for pancreatic endocrine tumors [12].

Tumor	Test
Insulinoma	Supervised 72hr fast, demonstrating Whipple’s triad and insulin/glucose ratio of >0.3 Selective arteriogram with intraarterial calcium injection and hepatic venous sampling Elevated c-peptide proinsulin levels
Gastrinoma	Elevated serum gastrin levels Elevated basal acid secretory rate Secretin stimulation test
Glucagonoma	Elevated glucagon levels
Somatostatinoma	Elevated fasting plasma somatostatin levels