gastrinoma

n. (Medicine) tumor which usually occurs in the pancreatic islet cells and causes overproduction of the hormone gastrin (can also occur in the stomach, spleen, and lymph nodes)

A gastrinoma is a tumor that secretes gastrin.It is frequently the source of the gastrin in Zollinger-Ellison syndrome.It is most commonly found in the pancreas and duodenum.
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[gas-tri-NO-ma]
A tumor that causes overproduction of gastric acid. It usually occurs in the islet cells of the pancreas but may also occur in the esophagus, stomach, spleen, or lymph nodes.