Abstract
The correct interpretation of the test result in serum gastrin made in suspected gastrinoma may be a problem. The negative predictive value of gastrin in the diagnosis of gastrinoma is relatively high, but the positive predictive value of tests to confirm the suspicion for gastrinoma is clearly lower because hypergasrinemia can cause a number of factors.
Normal gastrin values are different according to the laboratory. If necessary, it is therefore recommended testing gastrin in the challenge test with secretin.
Secretin test is superior calcium challenge test, but the problem is very limited availability of the test.