Gastrinomas are rare tumors that produce excessive amounts of the hormone gastrin, which stimulates the stomach to produce acid. These tumors are often found in the pancreas or the duodenum, the first part of the small intestine. The overproduction of gastrin can lead to a condition called Zollinger-Ellison syndrome, characterized by recurrent peptic ulcers and severe stomach acid secretion. Diagnosis of gastrinomas typically involves measuring gastrin levels in the blood and imaging studies to locate the tumor. Treatment options may include medications to reduce stomach acid, surgical removal of the tumor, or targeted therapies. Early detection is crucial for better outcomes.